RMPG05DR–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. 240 MOSSES AND FERNS CHAP. Still later the archegonia appear along the base of the anther- idial ridge (Fig. 126, B). The development of the antheridium (Fig. 128) is much like that of Ophioglossum, but the outer wall of the antheridium has normally two layers of cells. The spermatozoids, accord- ing to Jeffrey, probably correspond with those of the true Ferns. In a few cases observed by myself (Fig. 128, C) the primary division walls of the central part of the antheridium were not broken down
RMMCTKGW–. Fig. 34. Oosporenbildung von Peronospora Alsinearum (350/1). (Nach De Bary.) I'erotiosporineac sind die Antheridien schon frühzeitig durch ihre bedeutendere Kleinheit viel deutlicher von den Oogonien verschieden als bei den vorhergenannten Klassen, ihr Inhalt wandert durch einen Befruchtungsschlauch mit Ausschluss eines geringen Teils, der im Antheridium zurückbleibt, in das Oogon über und verschmilzt bei Pijthiwn und Phytophthora deutlich, bei Peronospora und Cystopus aber nicht deutlich wahrnehmbar, mit dem Inhalt des Oogons, der sich schon vorher in der Mitte desselben zur Eikugel (Oosphä
RM2AJC94P–Elementary botany . othallium of selaginella is nearlyall antheridium, so reduced has the gametophyte become here. 587. Female prothallia.—The female prothallia are devel-oped from the macrospores. The macrospores when mature havea rough, thick, hard wall. The female prothallium begins todevelop inside of the macrospore before it leaves the sporangium.The protoplasm is richer near the wall of the spore and at the 288 MORPHOLOGY. upper end. Here the nucleus divides a great many times, andfinally cell walls are formed, so that a tissue of considerable ex-tent is formed inside the wall of the spo
RMPG00XA–. Lessons in botany. Botany. F,g. i 9. Section of antheridial receptacle from male plant of Marchantia polymorpha, showing cavities where the antheridia are borne. 237. Archegonial plants.—In fig. 122 we see one of the female plants of marchantia. Upon this there are also very curious structures, which remind one of miniature umbrellas.. Fig. 120. Section of antheridium of mar- chantia, showing the groups of sperm mother cells. Fig. 121. Spermatozoids of marchantia, uncoiling and one extended, showing the two cilia. The general plan of the archegonial receptacle is similar to that 01 the anthe
RMMAB5WG–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . Ehipidium. — Eh. interruptum. a Ein ganzes Pflänzchen, aus einem dickwandigen, rhizoidentragendenHaupt- spross und aus büschelig-fächerartig angeordneten Aesten bestehend, letztere am Scheitel Oogonien oder Sporangien tragend (Vergr. schwach), h Ein Stück des verbreiterten Scheitels des Haupt- sprosses, mit den Basen der Aeste; ein Ast ist ganz gezeichnet, er trägt links ein entleertes Zoosporangium, am Scheitel ein Oogon (o) mit reifer Oospore, das von einem auf dünnem Nebenaste (»t) sitzenden Antheridium (
RM2ANF77W–Organography of plants, especially of the archegoniatae and spermaphyta . a ofthe other Bryophyta haveeither no stalk as in Riccia ora stalk (Fig. 1) which may beshort or long and is longest insome Musci. The stalk, unlikethat of the antheridium, has notmerely the function of bringingthe neck of the archegoniuminto a favourable position, but,where it is massive, is destinedto be of use to the embryo,and after fertilization has takenplace it may grow to a con-siderable extent (see Fig. 119).The embryo bores in the first instance into the stalk and may go no further,as in Nanomitrium (Fig. 120),
RMPG41D4–. Essentials of botany. Botany; Botany. Fie. 192. Section through An- theridial Eeceptaole of Mar- chantia. (Magnified.) a, antheridium. (f) The female receptacles, stalked structures with finger-like re- curved arms radiating from the center. With the magnifying glass examine the under surface of a very mature receptacle and note the young sporophytes, or spore-plants, hanging from the receptacle. Draw. 344. Minute Structure of Thallus and Buds. — Cut thin cross-sections of the thallus and examine with l.p. and then with m.p. Note : (a) The general structure of the thallus, with a firm upper
RMME6K3E–. Die Natürlichen Pflanzenfamilien nebst ihren Gattungen und wichtigeren Arten, insbesondere den Nutzpflanzen, unter Mitwirkung zahlreicher hervorragender Fachgelehrten begründet . Fig. 87. Ycmcherüi sessilis (Vaucli.) De Canil. A, B Entstehung eines Antkeridiums {a) an dem Aste (h) und des Gogoniums (0/7); 6'geöifnetes Oogonium , si Schleimtropfen ; Z» Spermatozoiden ; A'Befruchtungsstadium ; i«" reife Oospore {osp), a entleertes Antheridium. {A, B, E, F nach Sachs, C, D nach Frings heim, 250/1.) Die Keimung der Oospore findet erst nach einem Ruhestadium statt; die äußeren Membranen werd
RM2ANCFJK–A text-book of mycology and plant pathology . HIGHER FUNGI 125 antheridium, which is cut off by a partition wall. The wallsbetween the two organs are dissolved and the male nucleus passesthrough the opening formed wanders toward the egg nucleus withwhich it fuses. Immediately after fertilization, the oogonium beginssteady growth, and some of the outer cells formed become the cover. Fig. 39.—Diagrammatic representation of the development of the ascogenoushyphal system. {After Claussen.) cells of the perithecium. But ascogenous hyphse are formed, whichcontain two nuclei, then four nuclei by divi
RMPG2M56–. Parasitic fungi of Illinois / by T.J. Burrill. Fungi. Parasitic Fungi of Illinois. 389 these swells to two or three times the diameter of the thread, and is separated from it by a transverse partition. It now con- stitutes the carpogonium, homologous with the pistil of the flowering plants. The other branch, the antheridium, remains cylindrical, and is closely applied to the carpogonium, bending over its summit. A septum is formed near the tip, dividing off a small cell, whose contents, passing into the carpogonium, effect its fertilization. Slender branches now arise on all sides from near
RMMCKWKE–. , n ^i;" Fig. 54. Onion Diseases. a. Downy mildew, b. mature conidiophore and conidia of Peronospora schleideni, c. fertilization of the female oogonium by the male antheridium, d. oospore (a. to d. after Wh^tzel), e. onion smut, /. spore ball of the smut fungus, g. spore germina- tion, formation of sporidia at x, h. Vermicularia anthracnose, i. section through acervulis of Vermicularia cirdnans. j. setae and spore formation in V. circinans {e. to g., i. and j. after Thaxter), k. pink root of onion, healthy and diseased bulbs, I. pink root of onion showing nipple formation, m. a formald
RM2ANDW8P–Organography of plants, especially of the archegoniatae and spermaphyta . htca Eotanica, viii (1SS7), discusses my views. DEVELOPMENT OF THE ANTHERIDIUM 179 greatly of what we find in the primordium of the antheridium of theOsmundaceae (Figs. 133, III ; 134)- Osmunda. In Osmunda (Fig. 134) many cell-walls arise, inclined inthree directions in space, which lead to the formation of an antheridial stalk ;then follows a wall curved in a cap-like manner which corresponds withthat which in Marattia, Equisetum, and Lycopodium, separates the opercularlayer from the cell within, and then, by further di
RMPG05NA–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. IV. THE ANTHOCEROTES 129 arise is the inner of two cells formed by a transverse wall in a surface cell. The outer cell (see Figure 67, B) divides almost immediately by another wall parallel with the first, so that the group of antheridia is separated by two layers of cells from the surface of the thallus. The inner cell in A. Pearsoni at once develops into an antheridium; but in most species the cell divides first by a longitudinal wall into two, each of which. Fig, 67.—Anthoceros Pearsoni. De
RMMAAHH2–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . Nitella ornithopoda. a f. laxa, nat. Grösse; h eine der f. moniliformis sich nähernde Form aus Coirabra; c Blatt, Vergr. 12; d vierzelliges Blattende, Vergr. 90; e Blattenden mit Mucro, Vergr. 90; f Blattenden ohne Mucro, Vergr. 90; g Kern, Vergr. 60. Die Fortpflanzungsorgane stehen nur ausnahmsweise an der ersten Theilungsstelle der Blätter; Antheridien und Sporenknöspchen zusammen oder auch getrennt an verschiedenen Strahlen desselben Blattes, gewöhnlich je ein Antheridium und ein Sporenknöspchen zusammen.
RM2AWPTN1–The structure & development of the mosses and ferns (Archegoniatae) . Fig. 221.—Development of the autheridium, X 190. A, Longitudinal section through the antheridia!meristem showing antheridia of different ages ; B, longitudinal section of young antheridium,X375 ; C, two sections of a terminal, single antheridium, nearly ripe, X190 ; D, threetransverse sections of young antheridium, X 190 ; 0, opercular cell. eusporangiate Ferns, the antheridium mother cell is dividedinto an inner and an outer cell, of which the inner one forms atonce the sperm cells. When the antheridium arises at the endof
RMPG4GH0–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 173 This binucleate cell after fusion of its nuclei develops into the one ascus characteristic of the genus. The ascus nucleus by- division gives rise to the spore nuclei and the spores are cut out of the periplasm by reflexion of the astral rays. In Erysiphe** the oogonium and antheridium arise in a very similar way, the oogonium being somewhat curved. Feri;ilization is also similar consisting of the union of two gametic nuclei. After fertilization the oospore nucleus divides and the oogonium de
RMMAB5WA–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . Phytoplithora. — a, h Ph. omnivora. o Ein kleiner Conidienträger, unter Wasser entwickelt (Vergr. 90, nach de Bary). h Ongon mit reifer Oospore und Antheridium (Vergr. 375, nach de Bar}-)• c, d Ph. infestans. c Drei Conidien- träger aus einer Spaltöffnung (sf) hervorwachsend, mit blasigen Auftreibungen (m) unter den früheren Abschnürungsstellen der Conidien (Vergr. 120, nach Frank). ä Conidienkeimung. 1. Austritt der Schwärmer aus dem Scheitel der citronen- förmigen Conidie. 2. Zwei freie Schwärmer. 3. Schla
RM2AWR7JG–The structure & development of the mosses and ferns (Archegoniatae) . groups of spermcells are completely separated by one of these sterile cells(Fig. 207, F), but this is by no means always the case,and does not justify Belajeffs ^ interpretation of each grouprepresenting a separate antheridium. It is simply a morecomplete separation of the two primitive groups of sperm cells 1 Belajeff{3), p. 330. 2 Belajeff, I.e. 2 D 402 MOSSES AND FERNS CHAP. which is indicated by the first vertical wall in the central cellof the antheridium of all Leptosporangiatae. The divisions inthe central cells are v
RMPG1JR1–. The British Charophyta. Characeae. STRUCTURE AND DEVELOPMENT. 49 to four) of long whip-like filaments (c). The filaments are divided by transverse septa into about 100 to 200 disc-shaped cells, each of which contains an antherozoid. The number of antherozoids produced by a single antheridium has been computed at 20,000 to 30,000. The filaments form a dense tangled mass in the centre of the antheridium. A careful study of the development of the anthero-. JPia. 20.—Development of antherozoids (after Guignard). i. Early- stage after nucleus has moved to one side of cell. ii. Later stage showing
RMMAB5TR–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . Cystopus. — a C. candidus. Ein Mycelast mit drei Conidien abschnürenden Aestchen, alle Conidien gleichartig (Vergr. 400). b C. cubicus. Eine Conidien- kctte mit steriler Endconidie (t) (Vergr. 400). c—f C. candidus. c Ein Oogon mit heranreifender Oospore, von der aus Periplasmafäden nach der Oogonwand ausstraMen, oben ein Antheridium (Vergr. 400). d Eine keimende Oospore, noch von der Oogonwand locker eingehüllt, der Inhalt ist in der hervorgestülpten Bhise in Schwärmsporen zerfallen (Vergr. 400). e Ein Mvce
RM2ANF9CK–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. I. Marchantia polymorpha. A^ antheridium withmucilage-papillae, p, at its base. B, spermatozoids. A, mag-nified 90. B, magnified 600. After Strasburger. Fig. 2. Phascum cuspidatum. Stem inlongitudinal section. 5, leaves ; /, paraphyses;cr, archegonium ; a«, antheridium. Magnified45. After Hofnieister. Lehrb. which Stand in the axils of leaves as in the acrogynous Hepaticae, and therethey secure that the contents of the antheridium do not remain in the axilsof the leaves when they are discharged. We find similar rela
RMPG4A3M–. Foundations of botany. Botany; Botany. THE EVOLUTIONARY HISTORY OF PLANTS 303 â¢â a development the macrospore produces an endosperm whicli is really a small cellular prothallium, concealed in the ovule. The microspore contains vestiges of a minute prothallium. In the angiosperms the macrospore and its prothallium are still less developed, and the microspore, or pollen grain, has lost all traces of a prothallium and is merely an antheridium which contains two generative ceUs.^ These are most easily seen in the pollen grain, but sometimes they are plainly visi- ble in the pollen tube (Fig. 16
RMMCR7TM–. Fig- 44- (B. 653.) I 250 fach. Conidienträger von Peronospora parasitka aus einer Spaltöffnung der Stengel- Epidermis von Cnrdammc pratensis hervortretend (der Träger rechts ist abgeschnitten). II—VI ca. 800 fach. Oosporenbildung und Befruchtungsvorgang bei Pythhtm gracile in ihren successiven Stadien, nach de Bary: II Oogon und Antheridienast zu definitiver Grösse gelangt. III Das Antheridium durch eine Querwand abgegrenzt. IV Im Oogon hat sich die Eiballung vollzogen, zwischen Ei und Oogoniumwand eine dünne Periplasmazonc; das Antheridium hat einen Be- fruchtungsschlauch in das junge Ei hi
RM2AJDD5B–Elementary botany . blight (Phytophthora in- Gonidia of potato festans). b, an older stage showing how the branch enlarges where blight forming zoogo- it grows beyond the older gonidium. (After de Bary.) nidia. (After de Bary.) the eggs mature without fertilization. This maturity of the egg withoutfertilization is called parthenogenesis, which occurs in other plants also, butis a rather rare phenomenon. 396. In fig. 199 is shown the oogonium and an antheridium, and theantheridium is carrying in the male nucleus to the egg cell. Spermatozoidsare not developed here, but a nucleus in the antherid
RMPG0R4H–. Essentials of botany. Botany; Botany. Fig. 158. End of a Main Shoot of a Stonewort, Chara. (About natural size.) Fig. 159. Part of a "Leaf" of Fig. 158. (Considerably magnified.) u, antheridium; u, oogonium. At the right are a young antheridium and archegonium. This plant is a familiar object, waving as it does from rocks, piles, and wharves alongshore. Terrestrial genera and species of green algge are not uncommon.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustr
RMME6JW9–. Die Natürlichen Pflanzenfamilien nebst ihren Gattungen und wichtigeren Arten, insbesondere den Nutzpflanzen, unter Mitwirkung zahlreicher hervorragender Fachgelehrten begründet . Fig. 119. Chara fragilis Desv. A mittlerer Teil eines B. (6) mit 1 Antheridium (a) und 1 Sporenknospe (S); c deren Krönclien; ß sterile Seitenblättchen; ß' größere Seiten- stralilen neben der Fr. ; ß " die Bracteolen aus dem Basilar- knoten des Antheridiums entspringend. B ein junges Anthe- ridium (a) mit einer noch jüngeren Sporenknospe (SK); tc die Knotenzelle des B.; n die Verbindungsstelle zwischen jener un
RM2AWYXJX–A morphological study of some members of the genus Pallavicinia . Pallavicinia Zollingeri. A. Segment of the frond of an antheridial plant, x 25 (about). B. A portion of A, more highly magnified. C. Longitudinal section of the shoot, passing through an antheridium, and showing the strand of conducting tissue. D. Cross-section of a segment of the frond, showing the position of the antheridia on the dorsal surface of the midrib. METHODS II The cells of the ventral part of the midrib have thick walls in whichare pits elongated transversely. These pits are in lines extending roundthe cell, and for
RMPG41DA–. Essentials of botany. Botany; Botany. 268 ESSENTIALS OP BOTANY. Fie. 192. Section through An- theridial Eeceptaole of Mar- chantia. (Magnified.) a, antheridium. (f) The female receptacles, stalked structures with finger-like re- curved arms radiating from the center. With the magnifying glass examine the under surface of a very mature receptacle and note the young sporophytes, or spore-plants, hanging from the receptacle. Draw. 344. Minute Structure of Thallus and Buds. — Cut thin cross-sections of the thallus and examine with l.p. and then with m.p. Note : (a) The general structure of the t
RMMEJXFP–. Die Bedingungen der Fortpflanzung bei einigen Algen und Pilzen . Vaucheria repens (Fig. 2 A) bildet meistens nur ein Antheridium neben einem Oogonium. Dieses ist schief eiförmig und endigt in einen kurzen Schnabel, der fast horizontal, d. h. dem Faden parallel liegt. Die reife Oospore hat mehrere zerstreut liegende bräunliche Flecke (Degenerationsprodukte des Chlorophylls). Vaucheria clavata (Fig. 2 B) bildet bald ein, bald zwei Oogonien seithch vom Antheridium. Das Oogonium ist schlank eiförmig und en- digt in einen vertikal stehen- den Schnabel. Nicht selten, besonders in Zuckerlösung^en,
RM2AFKJ0X–. The structure and development of mosses and ferns (Archegoniatae). ium. Hestudied in detail their development, which differs considerablyfrom that of the other Mosses. The antheridium arises froma single cell whose position corresponds to that of a lateral budon an ordinary branch. This cell grows out into a papilla andbecomes cut ofiF by a transverse wall. The outer cell continuesto elongate without any noticeable increase in diameter, and aseries of segments are cut off from the terminal cell by wallsparallel to its base, so that the young antheridium consists ofsimply a row of cells, comp
RMPG05Y3–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. so MOSSES AND FERMS CHAt. cell are somewhat irregular, but more numerous than in Riccia, so that the stalk of the ripe antheridium is more massive (Fig. i6). In the upper cell a series of transverse walls is formed, varying in different species in number, but more than in Riccia, and apparently always perfectly horizontal. In Marchantia polymorpha Strasburger (2) found as a rule but three cells, before the first vertical walls were formed. In an undetermined species of Fiinbriaria (Fig. 15) pr
RMMAAHJN–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . legt, von denen 4 nach oben und 4 nach unten liegen. Die Oberfläche der 4 oberen Kugeloctanten sind sphärische Dreiecke, die der unteren ist nicht genau der Stielzelle abgegliedert und dreieckig, sondern die eine Ecke ist an entwickelt sich bei & u. c weiter. ^^^ ^iQQ ^ wo die Basalzelle in das d n. c scbematisclie Darstellung . ,, . ,. , . , -. ; - t»- , •. m, ., . A Antheridium hineinragt, abgestutzt. Die der weitern iheilungen im An- " ' ^ theridium. J^*^^ erfolgenden Zelltheilungen gehen in de
RM2AWPRA7–The structure & development of the mosses and ferns (Archegoniatae) . When the antheridium arises at the endof a filament, the divisions in the terminal cell are very muchlike those in Osmunda. In the mother cell three intersectingwalls enclose a tetrahedral cell, which then has the cover cellcut off by a periclinal wall. In both forms of antheridium thesubsequent history is the same. The central cell divides firstby a transverse wall, followed by vertical walls in each cell, andsubsequently by numerous divisions which show no definitearrangement (Fig. 221, C), and produce a very large number
RMPG05HA–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. 198 MOSSES AND FERNS the antheridium ripens, these gradually assume a bright orange- red colour. The development of the stalk varies in different cases. Sometimes it consists of a row of several cells, some- times the antheridium is almost sessile. The lowermost seg-. FlG, 103.—Funaria hygrometrica. A, Antheridium that has just discharged the mass of sperm cells (B), X300; C, spermatozoids, X1300; D, paraphysis, X300; E, male "flower" of Atrichum iindulatum, X6. ments of the apical c
RMMCTJ5J–. Fig. 292. A Lahoulbenia crisiata Thaxt., C'arpogon und Antheridium , tr Trichogyn. — B L. europaea Thaxt. — C L. elongata Thaxt. — D Teratomyces Actobü Thaxt. — E Diplomyces Actobiunus Thaxt. von der Rückseite. — F Rliachomyces lasiophorns Thaxt. — G Cliaetomyces PinophiU Thaxt. — E Sphaleromyces Lathrobii Thaxt. (Alles nach Thaxter, ü spiegelbildlich.) die nach vorn und hinten zu je einem Paare angeordnet sind. Auf dem hinteren Paar er- heben sich die erwähnten Auswüchse. Das vordere Paar entwickelt 2 kurz gestielte Perilhecien, an deren Rasis, innen und oberhalb, 2 oder mehr Paare von Anhä
RM2AJBJX5–Elementary botany . is the vegetative cell of the prothallium, while the smaller one, since it later forms the sperm cells, is the generative cell. This generative cell then corresponds to the central cell of the antheridium, and the vegetative cell perhaps corresponds to a wall F- cell of the antheridium. If this is so, then the Germinating spores male prothallium of angiosperms has become (P°J]en grams) of pel-r & r tandra; generative reduced to a very simple antheridium. The nucleus in one undi-r ., ,, , , , r ,.,. ,. vided, in other divided farther growth takes place alter fertilization,
RMPG00YP–. Lessons in botany. Botany. Fig. 96. Young antheridium and oogonium of Vaucheria , , . ,t sessilis, before separation from contents of thread by from a main thread. A a sep um. septum is formed which separates an end portion from the stalk. This end cell is the antheridium. Frequently it is collapsed or empty as shown in fig. 97. The protoplasm in the antheridium forms numerous small oval bodies each with two slender lashes, the cilia. When these are formed the antheridium opens at the end and they. Fig. 97. Vaucheria sessilis, one antheridium between two oogonia. escape. It is after the esca
RMMAAHJ1–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . Nitella capitata f. dissoluta. Natürl. Grösse. Quirls sind bis 4 cm lang, die weiblichen mit 2—3 Sporenknöspchen. Die männlichen (vergl. Fig. 34) haben neben dem Antheridium fast regelmässig nur 2 Seitenblättchen, stehen aber ebenso in aufgelösten Quirlen wie die weiblichen. Im Quirl finden sich 1—2 Zweige, welche dem Stengel gleichen und wieder aufgelöste Quirle und kleine Köpfchen tragen, ausserdem aber noch mehrere, welche nur 1—3 kleine Köpfchen entwickeln ohne längere Blätter. Alle andern Theile der Pfl
RM2AX1R1X–The elements of botany for beginners and for schools . enwrapped by tubular cells twisted around it: by the side of this is asmaller and globular antheridium. The latter breaks up into eight shield- FlG. 553. Agarum Tumeri, Sea Colander (so called from the perforations withwhich the frond, as it grows, becomes riddled); very much reduced in size. Fio. 554. Upper end of a Rockweed, Fucus vesioulosus, reduced half or more,b, the fnictifioatjon. 168 CRYPTOGAMOUS OR FLOWEBLESS PLANTS. [SECTION 17. shaped pieces, with au internal stalk, and bearing long and ribbon-shapedfilaments, which consist of
RMPG1JRC–. The British Charophyta. Characeae. III. IV JTiQ. 18.—Development of antheridium of Nitella fiexilis (after Sachs), i. Early stage showing young antheridium divided into eight equal parts by the growth of two vertical walls, at right angles to one another, and a horizontal wall. ii. Further stage showing each eighth part divided into an exterior and interior portion, iii. Later stage showing interior portion again divided, making three layers, the outermost expanding tangentially to form the plates or shields, the middle growing radially to form the mauubria, and the inner- most forming the h
RMMAB5TE–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . ^ / Peronospora. â a P. arborescens. Ein Oogon mit heranreifender, von Peri- plasma (pZ) umgebener Oospora, a Antheridium (Vergr. 500, nach de Bary). 6â/" Keife Oosporen von verschiedener Structur: h P. calotheca, c P. Myoso- tidis, d P. Valcrianellae, e P. Corydalis, die verhältnissmässig dünn- wandige Oospore (osp) bleibt hier in das dickwandige Oogon (o//) eingeschlossen, /â P. Ho lost ei (bâf nach der Natur, Vergr. 300). mit Warzen oder zu einem Netzwerk vereinigten kräftigen Leisten besetzt ist
RM2AXEWE6–Text-book of structural and physiological botany . alis an- gonia <^ and leaves <5 (x 400); 11. antheridium burst- tipyretica, with an inner ing, and allowing the antherozoids a to escape and outer peristome (x 350)- (after Schimper, x 30). forms in which the, growth is terminated by the productionof antheridia or archegonia at the apex of the stem oftenexhibit proliJicatio?i of the bud, as in Polytrichum (Fig.427 IV.). Axillary buds by the side of the theca or of theantheridia often develope also by a process of renewal,forming growths known as innovations. 3 o6 Structural and Physiolog
RMPG4H33–. The fungi which cause plant disease . Plant diseases; Fungi. Fig. 47.—^P. citriophora; de- velopment of swarmsporea from sporangia. After Smith and Smith. and the contents of the antheridium are carried over to the egg by a fertilizing tube. Members of the genus are aggressively parasitic only under most favorable environmental conditions of heat an(f moisture. Some sixteen species are known. P. de baryanum Hesse, is most com- mon''"'' as the cause of "Damping Off." Zoosporangia or "conidia" globose to eUiptic, usually papillate, 20-25 n; gemmae similar in form and s
RMMAAJ3T–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . Vaueheria littorea Hoffm.-Bang. a Zweigstück mit einem Oogoniuni. b Zweig- spitze mit einem Antheridium. Yergr. 110. (Nach Nordstedt.) 4. V. littoreu Hofm.- B a n g. Fig. 184. Der vorigen Art sehr ähnlich; das Oogonium je- doch an der Spitze eines hakenförmigen Zweiges, in seinem unteren Theile eine chlorophyllhaltige Zelle ein- schliessend. Diöcisch. V. littorea Hofm.-Bang. — Ag. Spec. Alg. I. p. 463. — Nordst. Algol, smäsaker, in Bot. Notiser. 1879, p. ISO und 186, Taf. 2, fig. 1—6. V. clavata Lyngb. Hydr.
RM2AFMDP1–. Plant anatomy from the standpoint of the development and functions of the tissues, and handbook of micro-technic. B FIG. 125.—.4, Antheridium containing sperm cells; B, archegonium containing an eggcell which has been found by five sperm cells. All from Osmunda cinnamomea. (AfterCampbell.) probably malic acid, diffusing through the water from its placeof secretion in the archegonium. The sperm cell now fuseswith the egg. Following this the fertilized egg cell begins aseries of nuclear and cell-divisions leading up to the full-grownfern (Fig. 124, E); and this produces sporangia and spores es
RMPG04N4–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. LYCOPODINE^ 5" characteristic feature of the forest vegetation of those regions. A few belong to the more temperate parts of Europe and Amer- ica, and a small number, e. g., S. rupestris, S. kpidophylla, grow in dry situations. The Gametophyte Hofmeister (i) included Selaginella among the other Pteri- dophytes he studied, but he was unable to make out the earlier. Fig. 295.—A, B. C, Three views of the youn^ antheridium of Selaginella Kraussiana, X450; D, an older stage of the same, X480;
RMMCK5NB–. Fi(i. :>:;. â i//..i.-yx-.i c.'/i./i".',- ..n i.l.n.t.-- ..i t../..-.. â â â ,,a.-iâ,i.'. Hit.- (unuu.s haa caused distortion ami thii'kuiiing; tlie white poivellanous conidial cushionH shew uji distinctly â¢â¢} the dark background, (v. Tu1>euf jiliot.) swarming spores with two uiUH^ual lateral cilia. The egg-cells, produced .singly in each oog(jnium, are fertilized I'V an antheridium. The thick-walled oospores remain enclosed in the intercelhUar spaces of the host-tissue, and on germinating in sj>ring di.^chargc swarming spores. Cystopus candidus (I'tis.) I.<v. While b'u-i
RM2AFN5H5–. The structure and development of mosses and ferns (Archegoniatae). ther-idium approaches maturity, are often much compressed, butin Targionia hypophylla, where Leitgeb states that this com-pression is so great that the cells appear like a simple membrane,I found that, so far from this being the case, the cells wereextraordinarily large and distinct, and filled the whole spacebetween the body of the antheridium and the wall of the cavity,which in Leitgebs figures ((7), vi., PI. x.. Fig. 12) is repre- II MUSCINEJE—HEPATIC JE—M ARC 11AXTI ALES 51 sented as empty. The antheridium becomes sunk in
RMPG1KH5–. Beginners' botany. Botany. igS BEGINNERS' BOTANY Fig. 292.— Archego- NIUM OF Marchantia. ties in the receptacle. From the base of each cavity there arises a thick, club-shaped body, the antheridium. Within the anther- idium are formed many sperm-cells which are capa- ble of swimming about in water by means of long lashes or cilia attached to them. When the anther- idium is mature, it bursts and allows the ciliated sperm cells to escape. The archegoiiiophores are also elevated on stalks (Fig. 289). Instead of a simple disk, the recepta- cle consists of nine or more finger-like rays. Along the
RMMAAHJM–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . Entwickelung des Sporenknöspchens. — 1—S von Chara foetida. 1 Vergr. ca. 50. an Antheridium, sp Sporenknöspcben. 2 Junges Sporenknöspchen; Vergr. 70. 3 Die Zellen der SporenhüUe haben sich differenzirt (Vergr. 70) und in 4 (Vergr. 50) die nackte Eizelle umwachsen; in 5 schliessen sie schon oben zusammen und in 6 haben sich die Zellen des Krönchens schon abgegliedert. In 7 ist ein Sporenknöspchen mit geschlossenem Krönchen vor der Empfängniss- fähigkeit (5, C, 7 Vergr. 50), bei 8 die Spitze eines Sporenknöspc
RM2AWTF32–The structure & development of the mosses and ferns (Archegoniatae) . Fig. 174.—A, Ripe antheridium of O. Claytoniana, just ready to open ; B, the same dischsperm cells, x6oo; C, two spermatozoids, X 1200. the Polypodiaceae. There are but about two complete coils,and the hinder one relatively larger than in the latter forms.In swimming there is peculiar undulating movement, suggestiveof the spermatozoid of Equisetuvi. The Ardiegoniuiii The archegonia are only borne upon the large heart-shapedprothallia, and occupy the sides of the projecting midrib, where, 1 Ior details see Campbell (12), p. 6
RMPG41H1–. Foundations of botany. Botany; Botany. 246 FOUNDATIONS OF BOTANY continuity of the cell-cavity and (in young plants growing on soil) search for root-like portions, in those growing in water for branch- ing portions, and fruiting, organs in the form of swellings or short lateral branches. With a power of about thirty to sixty diameters sketch a selected plant of moderate extent as nearly complete as possible or else. Fig. 180.— Vaucheria synandra. A, a filament with archegonia and antheridia (considerably magnified); B, part of same much more highly magnified; o, oogonium; a, antheridium; C,
RMMAAHJ0–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . 3 Blättchen, von denen, wenn eine zweite Tlieilung eintritt, stets nur eins getheilt wird, während die andern einfach bleiben. Die Blättchen sind verhältnissmässig stärker als an sterilen Blättern, die zweite Fig. 41. j^ Zelle ist nur als kleines, sehr schmales Spitzchen aufgesetzt (Fig. 41«). Sporenknöspchen .2—3 unter dem Antheridium ebenso wie bei N. translucens sehr gedrängt stehend und von ähnlicher Gestalt, nur etwas grösser und mit derberer Membran der Hüllzellen. Der Kern tief gelb- braun (Sepia), ei
RM2ANCDWY–A text-book of mycology and plant pathology . hae are binucleate, and in this case the nucleushas a double chromosome number. Hence is suggested an alternationof generations. The life cycle of Pyronema may be displayed in a graphic formbeginning with the ascospore and ending with its production again.The diploid, or twenty-four chromosome condition, may be repre-sented by the double lines. This life cycle is contrasted with thewell-known one of the fern where a well-marked alternation of genera-tion is shown. Fern (After Claussen) Pyronema Spore Spore Prothalluim / Antheridium Archegonium My
RMPG1JRW–. The British Charophyta. Characeae. 44 BRITISH CHAROPHYTA. In Lychnothamnus and Nitellopsis the arrangement is apparently similar. In Lychnothamnus the oogonium, which is solitary, is produced separately from the central peripheral cell on the inner side of the branchlet, that is the side facing the stem or branch, and antheridia are normally produced from peripheral cells on either side of that producing the oogonium (Fig. 16 iii A and B). In Nitellopsis the only known. Pig. 16.—Position of reproductive organs in several genera. <J = antheridium, ? = oogonium in all figvires. i. Nitella f
RMMAB5W6–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . K-OL, 6/ f Pythiuni. — a P. de Baryanum. Ein Stück Mycel mit Sporangien (sp), rechts ein entleertes, Oogonien (o), Antheridien («) und einer intercalaren Conidie (/) (Vergr. ca. 250, nach Hesse), h P. proliferuni. Habitusbild des Mycels mit kugelig- citronenförraigen Sporangien (Vergr. circa 100, nach M. Ward), c P. proliferuni. Ein keimendes Dauersporangium, dessen Inhalt in der Blase in Sporen zerfallen ist (Vergr. ÜOO, nach M. Ward), d P. Arto- trogus. Ein stacheliges Oogon mit hypo- gynischem Antheridium
RM2AJD3R9–Elementary botany . cavities sunk in thetissue of the thallus. There is here no illustration of the antheridium of thisriccia, but fig. 259 represents an antheridium of another liverwort, and thereis not a great difference between the two kinds. Each one of those little rect-angular sperm mother cells in the antheridium changes into a swiftly movingbody like a little club with two long lashes attached to the smaller end Bythe violent lashing of these organs the spermatozoid is moved through the water,or moisture which is on the surface of the thallus. It moves through the canalof the archegoni
RMPG1JRM–. The British Charophyta. Characeae. STEUCTURE AND DEVELOPMENT. 45 the antheridia and oogonia are produced together on the inner side of the branchlets from one outgrowth arising from the central anterior peripheral cell of the branchlet-node taking the place of a bract-celL In Lamp-othamnium the oogonium is produced below or occasionally by the side of the antheridium (Fig. 16 iv A and B), in Char a the antheridium is produced below the oogonium (Fig. 17). Both oogonia and anthe-. Fio. 17.—Position of reproductive organs in Chara fragilis (after Strasburger) (x o. 45). Vertical section of bra
RMMAB3C7–. Dr. L. Rabenhorst's Kryptogamen-Flora von Deutschland, Oesterreich und der Schweiz . ^1f Fig. 44. Fegatella conica. Antheridienhöhle mit Antheridium im Längsschnitt, Verg. ^''^/i. Fig. 45. 8 c a p a n i a c o m p a c t a. Antiieridien mit haar- und blattförmigen Paraphysen. Verg. ''"/p (Nach K. Müller, Scapania-Monogr.J eine obere Zelle. Die obere teilt sich noch einmal quer, während die untere durch Längsteilung in zwei Zellen zerfällt. Aus den zwei unteren gehen nun die Antheridien hervor, sie entstehen also endogen. Da- durch unterscheiden sie sich wesentlich von der Bildungsweise be
RM2AFN5BX–. The structure and development of mosses and ferns (Archegoniatae). Fig. i6.—Fimbriaria Californica. A. Longitudinal section of a fully-developed malereceptacle, X8; B, longitudinal section of a nearly ripe antheridium, Xioo; C,young sperm cells, X6oo; D, spermatozoids, X1200. Fimbriaria. In the earlier divisions of the sperm-cells, eachcell shows two centrosomes (Fig. 17, i), and Ikeno does notrecognise any difference between these and the so-calledblepharoplast of Webber and other recent students of sperma-togenesis, who look upon the blepharoplast as a different organfrom the centrosome. A
RMPG41CN–. Foundations of botany. Botany; Botany. Pig. 203. — Section tlirough Anther- idial Keceptacle of Marchmitia. (Magnified.) a, antheridium. 337. Internal Structure. — Cut thin cross-sections of the thallus in the same way as for Physcia, making some pass through the cir- cular dots mentioned above. Exam- ine under a high power and note the different kinds and layers of cells composing the thallus. Note the character of the cells forming the upper and lower surfaces. Describe the cells which are next above those of the lower epidermis, their shape, color of contents, approximate num- ber of hori
RMMCP926–. Fig. 179—185. 179—182 Aphanochaete repens: 179 a Pflanze mit Antheridien (a) und Oogonien (<?), b Spermatozoiden, c Eizelle nach dem Ausschlüpfen, d Befruchtung. 180 Aplanospore. 181 Zoosporen, zwei noch in der Blase eingeschlossen, eine freie Zoospore und eine 1 Tag alte Keimpflanze. 182 Exemplar mit mehreren Borsten auf jeder Zelle. 183 A. püosissi?na, junges Exemplar mit zwei jungen Oosphären und einem Antheridium. 184 A. Hyalothecae. 185 A. polychaete (179 nach Huber, 180 300x nach G.S.West, 181 360x nach Berthold, 182 Orig., 183,184 nach Schmidle, 185 332 x , 400x nach Fritsch).
RM2AJCGF0–Elementary botany . ermato-zoids coming out ofthe antheridium, for when the prothallia Section of antheridia showing sperm cells, and spermato- are freshly placed in zoids in the one at the right- water the cells of the antheridium ab-sorb water. This presses on the con-tents of the antheridium and bursts thecap cell if the antheridium is ripe, andall the spermatozoids are shot out.We can see here that each one isshaped like a screw, with the coils at Fig. 307. l Different views of spermatozoids; first close. But aS the SpermatOZOidin a quiet condition; in motion ,. .. (Adiantum concinnum). be
RMPG0R54–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 128 PHYCOMYCETES. arise in tufts from the stomata; they are branched in various ways, and from each branchlet a single conidium is abjointed. The contents of the conidia emerge as swarming cells with two lateral cilia, or as vesicles which emit a germ-tube. The egg-cells occur singly in each oogonium, and are fertilized by an antheridium. The oospores remain long enclosed in the thick-walled oogonium.. Fig. S9.Ploj
RM2ANDTE4–Organography of plants, especially of the archegoniatae and spermaphyta . idium, each of them divides by two anti-clinal walls into the two sterile cells respect-ively b and c, d and e. Fig. 137, B^ and themother-cell of an antheridium out of whichthe two mother-cells of the spermatozoidsare developed. The dorsiventrality of theprothallus is here very apparent. The cellsb, c, d, e, which remain sterile, and which inmy view are wrongly designated wall-cells,take no part in the opening of the anthe-ridium. It is indeed clear that in so small antheridia the openingmechanism may be very simple. On
RMPG05JM–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. Fig. 91.—A, Male catkin of Sphagnum cymhifolium, X50; B, young antheridium of S. acutifolium, X350; C, opened antheridium of the same species; D, spermatozoid, Xiooo (about); E, female branch with sporogonium of S. acutifolium, slightly magnified; cal^ calyptra. A, C, E, after Schimper; B, after Leitgeb. the body of the antheridium. The first divisions in the body of the antheridium only take place after the stalk has become. Please note that these images are extracted from scanned page images
RM2AFHHX0–. The structure and development of mosses and ferns (Archegoniatae). two similar initials,X, X, X560; B, longitudinal section of an advanced prothallium of O. cinnamomea,X260; C, horizontal section of a similar one, showing two initials, X260. The prothallia are long lived if they remain unfertilised,and Goebel ((i6), p. 199) states that in O. regalis they mayreach a length of four centimetres. He also records a genuinedichotomy of the older prothallia of this species. The Antheridium f Under favourable circumstances the first antheridia appearafter about a month in O. Claytotiiana, and contin
RMPG05Y1–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MUSCINE^—HEPA TICJE—MARCH ANT I ALES SI seated as empty. The antheridium becomes sunk in the thallus precisely as in Riccia. The sperm cells are nearly cubical and the spermatozoid is formed in the usual way. The free spermatozoid (Fig. i6, D) shows about one and a half com- plete turns of a spiral. The cilia are very long, and the vesicle usually plainly evident. According to Ikeno (4), in Marchantia polymorpha the final division, resulting in the pair of spermatids, is unaccom- panied by a d
RM2AX1RB4–The elements of botany for beginners and for schools . enwrapped by tubular cells twisted around it: by the side of this is asmaller and globular antheridium. The latter breaks up into eight shield- FlG. 553. Agarum Tumeri, Sea Colander (so called from the perforations withwhich the frond, as it grows, becomes riddled); very much reduced in size. Fio. 554. Upper end of a Rockweed, Fucus vesioulosus, reduced half or more,b, the fnictifioatjon. 168 CRYPTOGAMOUS OR FLOWEBLESS PLANTS. [SECTION 17. shaped pieces, with au internal stalk, and bearing long and ribbon-shapedfilaments, which consist of
RMPG41B6–. Essentials of botany. Botany; Botany. Fig. 201. The Antheridium of a Moss {Funaria) and its Contents. a, antheridium; 6, escaping sperms (X 350); c, a single sperm of an- other moss (X 800).. Fig. 202. Portions of Fertile Plant of a Moss {Funaria). A, longitudinal section of summit of plant (X 100); o,, archegonia; I, leaves. B, an archegonium (X 550); e, enlarged ventral portion with cen- tral cell; n, neck; m, mouth.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations
RM2AFN5M1–. The structure and development of mosses and ferns (Archegoniatae). Fig. 15.—Fimhriaria sp. (?). A, Part of a vertical section of a young antheiidialreceptacle, showing two very young antheridia (J), X420; B-E, older stages. and lowest cell of the body of the antheridium, or the divisionsin these parts are more irregular. The separation of the cen-tral cells from the w^all is exactly as in Riccia, and the lowersegments do not take any part in the formation of the spermcells, but remain as the basal part of the wall. In Fimhriariathe top of the antheridium is prolonged as in Riccia, but inMarc
RMPG05RM–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. io6 MOSSES AND FERNS " CHAP. tion (Fig. 53, A), which separate a central cell, nearly tetra- hedral in form, from two outer cells. In the complete separa- tion of the central cell by these first two walls, Porella appears to dififer from the other Jungermanniaceae examined, (Leitgeb (7), ii., p. 44), where these first two peripheral cells do not reach to the top of the antheridium, and a third cell is cut off before the separation of the central part of the antheridium from the wall is co
RM2ANF8EW–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. 3. Opening cap of the antheridium in Musci. i, Funaria hygrometrica. Antheridium in profile; theopening cap consists of one cell. 2, Polytrichum. Emptied antheridium ; the opening is in section. 3, Catharineaundulata. Apex of an antheridium in longitudinal section ; the cells of the opening cap are marked b)- thedeposition of mucilage in their walls. may also take place gradually, and drops containing spermatozoids arethen found at the mouth of the pits, whence they can be either washedaway or removed by small anima
RMPG1JR6–. The British Charophyta. Characeae. 48 BRITISH CHAEOPHTTA. The chlorophyll-granules become yellowish-orange to red as the antheridium matures. The foot-stalk (Fig. 18 6), styled the flask-cell, is more or less flask-shaped, the narrower end projecting far into the interior of the antheridium. In the Nitellese, between the flask-cell and the node-cell, an extra cell (Fig. 18 c) is present.. Fio. 19.—Mature antheridium (after Prosper), i. Chara hispida. ii, iii. Chara tomentosa. i. General exterior view. ii. Interior view of single plate or shield with manubrium attached, iii. Apex of manubrium
RM2AFN60N–. The structure and development of mosses and ferns (Archegoniatae). cia, is strictly acropetal. The first stages are exactly likethose of Riccia, and the primary cell divides into two cells, apedicel and the antheridium proper. The divisions in the lower so MOSSES AND FERNS CHAP. cell are somewhat irregular, but more numerous than in Riccia,so that the stalk of the ripe antheridium is more massive(Fig. i6). In the upper cell a series of transverse walls isformed, varying in different species in number, but more thanin Riccia, and apparently always perfectly horizontal. InMarchantia polymorpha
RMPG4A3A–. Essentials of botany. Botany; Botany. "'â oph JeT"^ "â ^te or Fig. 207. Diagram of Life History of a Fern. An, antheridium; Ar, archegonium; s, sperm" e, egg-cell; e', egg. from the lower forms of plant life to the higher ones, it is only when the ferns are reached that alternation of genera- tions is shown in its most complete form. By this term a. Fig. 208. Illustrated Life History of a Fern. (The young fern-plant is Onoclea, Fig. 209.) process of reproduction is meant in which the offspring resemble closely not the' parent but the grandparent, as. Please note that thes
RM2AJC26Y–Elementary botany . 359. At the sametime the two cells which were formed inthe pollen grain (antheridium) from thecentral cell move down into the tube. Oneof these is the generative cell, or bodycell, and the other is called the stalk cell,though it is more properly a sterile half ofthe central cell. The nucleus of the gener-ative cell, about the time the archegoniumis mature, divides to form two nuclei,which are the sperm nuclei, and the onein advance is the larger, though it is muchsmaller than the egg nucleus. 625. Fertilization.—Very soon after thearchegonia are mature (early in June in th
RMPG2K5N–. Morphology of gymnosperms. Gymnosperms; Plant morphology. GINKGO ALES 207 becoming brown and forming a resistant beak that long persists as a cap on the sac. The pollen grains, carried well below the beak by the deepening of the chamber, send out their tubes in every direction into the adjacent nucellar tissue, but chiefly away from the embryo. 240 239 Figs. 235-240.—Ginkgo biloba: the male gametophyte; fig. 235, pollen grain, showing evanescent prothallial ceU and persistent prothallial cell; the mitosis in the antheridium initial will form the generative and tube cells; April 24; X500; fig
RM2AG8X2E–. Foundations of botany. eracomposing the group Chara-cece^ a group of green alg?ediffering widely from anyothers. They show in a won-derful manner simplicity ofcell-structure with a highdegree of organization, fig. 182.—Partof aLeaf of ng. isi, ^ 1 p 1 (Considerably magnified.) Scarcely less wonderful are „,antheridium; o, oogonium. At the the care and precision with ^ig^* are a young antheridium and ,.,,,.,, , , archegonium. which botanists have worked out their life history. As a study in evolution the Characecemay be considered as representing the highest develop-ment attained along the li
RMPG43MG–. The diseases of crops and their remedies : a handbook of economic biology for farmers and students. Plant diseases. 142 DISEASES OF CHOPS. Cure.—See those already described for destroying P. infestans (the potato-disease fungus). The Fusisporium of Cabbages {Fusisporium aurantiacum) has a similar life-history to F. solani. Fig. 47.—White Ensi Fungus or Cabbages {Cystopus candidus). A. Mycelium bearing couidia. x 195. B. Conidiuni (zoosporangium) producing zoospores, x 4^5. C. Oogoniom (1) and antheridium (2). x 195. D. Oospore (resting-spores). x 196. E. Inner membrane of oospore containing
RM2AFHH4F–. The structure and development of mosses and ferns (Archegoniatae). Fig. 196.—A, Ripe antheridium of O. Claytoniana, just ready to open; B, the samedischarging the sperm cells, X600; C, two spermatozoids, X1200; o, operculum. prothalHa, and occupy the sides of the projecting midrib, where,if the earlier ones are not fertilised, they may continue to formindefinitely; but no correspondence can be made out betweenthem and the initial cells, and while developed for the most partin acropetal order, new ones may arise among the older ones.23 354 MOSSES AND FERNS CHAP.. B The mother cell of the arch
RMPG3J2H–. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. Figure 87. Pnllavicinia Lyellii (After Sullivant.) Plant; part of thallus with involucre, perianth and ca- lyptra; part of perianth cut away to show young calyp- tra; capsule closed and open; antheridium enclosed in a leaf; elater and spores. in swampy places and on PALLAVICINIA. p. Lyellii S. F. Gray {Steetsia of authors) has a flat creeping thallus, J4 to nearly ^ inch wide, sometimes reaching four inches in length, with margin somewhat sinuate,
RM2AWT1KN–The structure & development of the mosses and ferns (Archegoniatae) . Fig. ZQ.—Hymenophylluin (sp). Development of the antheridium, X260. A, D, From Hvingspecimens; E, microtome section; B i, C 2, D i, optical sections; B 2, C i, D 2, surface viewof the same. margin. Goebel ^ has shown, however, that these archegonialgroups arise first near the growing point of the prothallial branch,and that they are simply separated by the intervention of zonesof sterile tissue. At the point where they arise the prothalliumbecomes more than one cell thick, and in all cases where thedevelopment could be cert
RMPG4CGC–. Diseases of truck crops and their control . Vegetables. Fig. 54. Onion Diseases. a. Downy mildew, b. mature conidiophore and conidia of Peronospora sckleideni, c. fertilization of the female oogomum by the male antheridium, d. oospore (a. to d. after Wh^tzd), e. onion smut, /, spore ball of the smut fungus, g. spore germina- tion, formation of sporidia at x, h. Vermicularia anthracnose, i. section through acervulis of Vermicidaria cirdnans, j. setae and spore formation in V. circinansXe. to g., *. and j". after Thaxter), k. pink root of onion, healthy and diseased bulbs, I. pirJc root o
RM2AFKXG4–. The structure and development of mosses and ferns (Archegoniatae). mber. Inall the younger stages met with by the waiter, the antheridiumlay horizontally nearly parallel wnth the axis of the shoot, andwas attached to the back of the antheridal chamber, instead ofat its base, as in the other genera. (Fig. 78, D.) The first division in the antheridium is transverse, and sep-arates the upper part from the stalk. The next divisions maybe alike in both of these cells, being vertical walls intersectingso as to divide both cells longitudinally into four similar cells.In the stalk, however, one of t
RMPG41J0–. Essentials of botany. Botany; Botany. 226 ESSENTIALS OF BOTANY felt-like masses which it forms. It must not be confused with moss protonema (Fig. 199) which also grows on damp earth. The protonema has many cross-partitions in the filaments (often oblique in position) and lacks other. Fig. 157. Yaucheria synandra. A, a filament with archegonia and antheridia (considerably magni- fied); 5, part of same much more highly magnified; o, oogonium; a, antheridium; C, a later stage oi B; D, end of a filament with a zoospore, z, escaping (highly magnified). characteristics shown in Fig. 157, A. It wil
RM2AWX4K0–The structure & development of the mosses and ferns (Archegoniatae) . Fig. io8.—Ophioglossiitn pedunculosuin (Desv.). A, B, Prothallia, X 2 ; T, the primary tubercle;C, antheridium, X200 ; D archegonium ; E, a young embryo (after Mettenius). closely to those of Ophioglossuin, are produced principally uponthe upper surface, the archegonia below. The latter correspondin structure to those of Ophioglossuni, but to judge fromHofmeisters figure the neck is somewhat longer and projects ?^ Hofmeister, I.e. J24 MOSSES AND FERNS CHAP.. more above the surface. The spermatozoids are described assimilar t
RMPG0607–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. 32 MOSSES AND PERNS have, as usual in such cases, decidedly denser contents than the peripheral ones. The lower one or two segments and the terminal ones do not take part in the formation of sperm cells, but simply form c A.,. Fig. s.—A-F, Development of the antheridium of R. glauca, seen in longitudinal section; G, cross-section of a young antlieridium of the same; H, antheridium of R. trichocarpa; I, sperm cells of R. glauca. Figs. E, F, Xiso; I, X6oo, the others X 300. part of the wall of t
RM2AWWFTD–Text-book of botany, morphological and physiological . and with the end of the funnel above the wallof the mother-cell; the upper part of this is cut off by a level septum as a covering cell; two,or even three, funnel-shaped walls may be formed in succession, so that the parietal layer of theantheridium consists of two or three superposed funnel-shaped cells and a covering cell (as inFig- 253). The mode of formation of the antheridium-wall is quite different in Osmunda, where itconsists below of two or three cells, upon which rest several of the upper cells which result fromthe division of the
RMPG00WG–. Lessons in botany. Botany. LIVERWORTS. H7. ^mm. Fig. 127. Marchantia plant with cupules and gemma? ; rhizoids below. Synopsis. Plant body ; flattened ribbon-like, green, with rhizoids on under surface ; grows in moist situations. 'ist. Plant with buds in little cups. The buds escape and propagate the plant. 2d. Male plants. Antheridial receptacle. Vegetative part. Antheridial cavities. fls rpliantia Three forms. "" Antheridium. rJLcLl *-HlX11 LICL (A liver- ' Spermatozoids. wort). 3d- Female plants. Archegonial receptacle. Archegonium. Egg. * 1 Capsule wall. Fruit capsule. -1 Spo
RM2AWR6NT–The structure & development of the mosses and ferns (Archegoniatae) . Fig. 208.—A, B, C, Sections made in three planes of the ripe antheridium of Marsilia vestita., X450 ;jr, vegetative prothallial cell; d, cover cell of the antheridium; D, E, spermatozoids, X900; v,the vesicle attached to the large posterior coils. is the small vegetative cell, in the basal cell of the antheridium,/*the lateral wall cells, and d the cover cell. Pilula7-ia approachesmuch nearer to the Polypodiacese in the structure of theantheridium (Fig. 209). The first funnel-shaped wall is muchmore frequently extended to th
RMPG41BP–. Foundations of botany. Botany; Botany. Fig. 208.—The Antheridinm ' of a Moss (FwnaHa) and its Contents. a, antheridium; b, escaping antherozolds, x 350; c, asin- gle antherozoid of another moss, X 800.. Fig. 209. — Portions of Fertile Plant of a Moss (Fimaria). A, longitudinal section of summit of plant, X 100; a, archegonia; I, leaves; B, an archegoniam, x 550; ti, enlarged ventral portion •with central cell; n^ neck; m, mouth. 346. Sporophytes. — That part of the reproductive apparatus of a common moss which is most apparent at a glance is the sporophyte or spore-capsule (Fig. 206). This i
RM2AWR679–The structure & development of the mosses and ferns (Archegoniatae) . Fig. 208.—A, B, C, Sections made in three planes of the ripe antheridium of Marsilia vestita., X450 ;jr, vegetative prothallial cell; d, cover cell of the antheridium; D, E, spermatozoids, X900; v,the vesicle attached to the large posterior coils. is the small vegetative cell, in the basal cell of the antheridium,/*the lateral wall cells, and d the cover cell. Pilula7-ia approachesmuch nearer to the Polypodiacese in the structure of theantheridium (Fig. 209). The first funnel-shaped wall is muchmore frequently extended to th
RMPG4GY4–. The fungi which cause plant disease . Plant diseases; Fungi. 98 THE FUNGI WHICH CAUSE PLANT DISEASE. 14 15 Fio. 67.—^P. Bchlcideni. 11. Mycelial threads between the large conductive cells of the leaf; (a) the mycelial thread; (b, b) branched or coiled haustoria; (c) branched haustorium wrapped about the nucleus. 13. Young conidiophorcs, (a, a) turn- ing toward the stoma, (b); (c) haustorium wrapped about the nucleus of the epidermal cell. 14. Mature conidiophore (a) with mature conidia, (c, c); (d) germ tube of conidium entering stoma. 15. Oospores, (a) mature oospore with old antheridium, (
RM2AJCRFP–Elementary botany . Fig. 272.Antheridium of a foliose liverwort (jungermannia).. Fig. 271.Foliose liverwort, male plant showing anthe-ridia in axils of the leaves (a jungermannia). Fig. 273.F«liose liverwort, female plant withrhizoids. quadrants, the wall forming four valves, which spread apart fromthe unequal drying of the cells, so that the spores are set free, asshown in fig. 276. Some of the cells inside of the capsule de-velop elaters here also as well as spores. These are illustratedin fig. 278. 500. In this plant we see that the sporophyte remains attached FOLIOSE LIVERWORTS. 239 to the
RMPG4A3E–. Essentials of botany. Botany; Botany. THE PTERIDOPHYTES 285 365. Discussion. â The life history of a fern differs in a striking way from that of a liverwort or moss. Ascending ...â An â Sporangi'"". "'â oph JeT"^ "â ^te or Fig. 207. Diagram of Life History of a Fern. An, antheridium; Ar, archegonium; s, sperm" e, egg-cell; e', egg. from the lower forms of plant life to the higher ones, it is only when the ferns are reached that alternation of genera- tions is shown in its most complete form. By this term a. Please note that these images are extracted from scanne
RM2AXDBRH–Plants and their ways in South Africa . Fig. 195.—Vaucheria. A, B, formation of antheridia and oogonia ; /z, malebranch ; a, antheridium ; og, oogonium ; C, oogonium opening to exude thedrop of mucilage, si; D, spermatozoids ; E, spermatozoids entermg oogonium ;F, a, an empty antheridium ; osp, oogonium with oospore or fertilized oosphere(magnified). (After Goebel and Pringshein.) as having no root, stem or leaves, and in having one-celled fruitingorgans. It may be divided into three subdivisions. A. Alg/f:.—Most of the plants composing the green floatingscum on ponds, which is sometimes calle
RMPF9FG0–. Deutsche Flora. Pharmaceutisch-medicinische Botanik. Ein Grundriss der systematischen Botanik zum Selbststudium für Aerzte, Apotheker und Botaniker. Plants; Medicinal plants. 122. 1. Andreaea ritpeslris. c die Mittel- eäule. V Scheide. 2. "Von Bit. ent- blösster Fruchtstiel am Grunde mit unbefruchteten Archegonien a besetzt bei v die kleine Scheide. 3. Haube. 4. Antheridien und Paraphysen 2». 5. Archegonien a.a mit Paraphysen p und Hüllblättern (perichaetium) h.. Sphagnum aciitifoUum. 1. Fruchttragende Pfl. 2. Reifes Antheridium. 3. Antherozoid. 4. Weibl. Bim. längsdurchschuitten. a Bef
RM2ANDPAY–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. 140. Lycopodium inundatum. i, few-celled prothallus ;/?, basilar cell. 2, prothallus with antheridium, ^«; i/, injuredcell. 3, older prothallus with antheridia, Aft, and meristem, MU, injured cell; b, basilar cell. 4, prothallus with archegonia, A,and an embryo showing cotjdedon, Co, and protocorm, B. Allmagnified ; after De Bary. Fig. 141. Lycopo-dium.inundatum. Pro-thai us with arche-gonia, A. ^lagniCed. deal with an inherited character from a primitive chlorophyllous prothallusor with a condition produced by int
RMPG3W89–. Mosses with a hand-lens; a non-technical handbook of the more common and more easily recognized mosses of the north-eastern United States. Mosses. Pi^ATi; XXV. O. speciosum (From Bry. Eur.). 3 and 5. Leaves. 7, 8. 10 and 15. Capsules and peristome. Pi,ATE XXVI. 0. sordidvm (From SulHv. " Icones Muse. Suppl.'*) 1. Plants natural size. 3. Leaves. 4. Leaf sections. 5. Cellular struc- ture of leaf base and apex. 12, Antheridial branch with antheridium and paraphysis. 11. Segment of peristome highly magnified. 13. Superficial stoma. The other figures are self-explanatory.. Please note that t
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