RMREF5XR–. Comparative morphology of Fungi. Fungi. UREDINALES 567 (Strelin, 1912). The close agreement which has been found in this respect between the manner of formation of spore and of peridium of the aecidia and uredinia is suggestive. In Uromyces Glycerrhizae, plas- mogamy appears to occur somewhere on the mycelium, as the hyphae which form the uredinium are already binucleate (Olive, 1913). These primary uredinia which have arisen on the uninucleate mycelium often differ in their appearance from the secondary ones formed later on the binucleate mycelium, e.g., they are distinguished by a greater
RMRH2XR9–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 92 UROMYCES the leaves. The mycelium of the secidial stage is said to be pei-ennial in the host ; Dietel says that in some localities the eecidiospores can re- produce themselves, and that then the uredo is suppressed. Both this species and the preceding are distinguished from U.flectens in the fact that the sori are smaller, distributed more uniformly over the leaf, and do not cause distortions. The tecidium is rare in Britain (I have seen specimens only from Perth); most of our records of Uromyces on T. repen
RMRDX0FN–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. 214 PROTOBASIDIOMYCETES [CH. fertile cells of Phragmidium violacetun was shown by Blackman and subse- quently by Welsford to be derived from one of the smaller cells at the base of the fertile layer. It is thus a vegetative nucleus; it enters the fertile cell by migrating through the wall, becoming much drawn out and laterally com- pressed. It leaves a pore which may be identified after its passage (fig. 192).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colo
RMRDX0TX–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. VII] USTILAGINALES 193 uninucleate or binucleate (fig. 160), but it is not known whether fusion takes place in them. The multinucleate character of the mycelial cells strongly suggests that no preliminary pairing of the nuclei occurs. In Ustilago Zeae Lutman also observed a mycelium of multinucleate cells; at the time of spore-formation binucleate and uninucleate cells and finally uninucleate spores appear. Tilletiaceae The principal genera of the Tilletiaceae are Tilletia,Entylofna, Tuburcinia, Urocystis and Doassansia. They have in comm
RMRH28WK–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 2 SPERMOGONES The mycelium in the leaf is strictly localised, forming little knotted masses {plectenchi/ma) just beneath the epidermal cells of the affected spot; all the cells of this mycelium are uninucleate. Some of these hyphae turn upwards, remaining densely crowded and more or less parallel to one another, and enclose the flask-shaped cavity, at length converging to a point above it and piercing the epidermis at that place. Then the upper ends of these hyphse diverge and form a brush-like bundle surroundi
RMRDX13N–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] LABOULBENIALES 175 the appendages aside and take up an apparently terminal position. The development is very uniform, and has been described by Thaxter in some detail for Stigmatomyces Baeri. Here, the upper cell of the receptacle divides into two; the lower of these remains as part of the receptacle, and the upper grows out (fig. -},6d) to form the female organ and ultimately. Fig. 136. Stigmatomyces Baeri Peyritsch ; development of the perithecium; a. shows the two-celled receptacle, a single appendage bearing five simple, endogenou
RMRH2XPC–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. Pig. 50. U. Fabae. 'IVleutospores and uredospore on Vicia Cracca.. Fig. 51. U. Fabae. Telento- spores and uredospore on Vicia sepivm.. 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 may not perfectly resemble the original work.. Grove, W. B. (William Bywater), 1848-1938. Cambridge, University Press
RMRH2WRR–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. his IMCCINIA the fusiform shape, thin walls, and pale colour of the teleutospores, which often become totally devoid of thickening al tin- apex, by the dropping off of the pale thickening cap, ou germination. /'. punctata is additionally distinguished by the presence of the aecidium. Fischer explains the fact, that distortions more usually accompany /'. Valantiae, by the consideration that infection takes place from the basidiospores mainly through the cuticle of young ami still growing parts,
RMRDTP7N–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. in] PLECTASCALES 73 enclosed them between glass plates so as to reduce the entrance of air, and the development of conidia. Similarly Zukal a few years later obtained sclerotia by excluding air. The formation of the perithecia in Brefeld's material was initiated by the appearance of pairs of simple, stout hyphae which twisted round one another (fig. 32), and from one or both of which branches later arose. Brefeld regarded them as possibly oogonial and antheridial. A further study of these organs, the simple form of which suggests a compar
RMRDX13C–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. 176 PYRENOMYCETES [CH. All the cells are uninucleate. The female cell is called by Thaxter a carpogonium or carpogonic cell in conformity with the term used for the Red Algae, but it obviously corresponds to the cell in which fertilization is now known to occur in other Ascomycetes and will therefore here be termed the oogonium. In Stigmatomyccs Baeri the trichogyne is simple (fig. 136^, e) but in many other members of the group it undergoes frequent septation and branches freely. The apices of the branches are alone receptive and may str
RMRH2T60–. The British rust fungi (Uredinales), their biology and classification. Uredineae. :300 KUEHNEOLA several cells as in Phraginidium, but the wall is faintly coloured or colourless, and smooth ; pores one in each cell, apical. This genus is not confined to Rosacese, being recorded on Malvaceae in America, where also both the British species are found. It is not closely allied to Pliragmidium: the wall of the teleutospores and the germ-pores are quite different. But I am also of the opinion that the two species included here are not in reality congeneric. 1. Kuehneola albida Magnus. Uredo Millle
RMRE2FXP–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. UREDINOPSIS 379 UREDINOPSIS Magnus. Teleutospores solitary, extracellular, hyaline, septate. Uredo- sori subepidermal, with a distinct peridium; uredospores hyaline, pedicellate, without germ-pores. On Ferns. This genus is distinguished from all others by the fact that the teleutospores are dispersed without order among the cells of the mesophyll. There are three known forms of spores, which seem to occur simultaneously, and not in a fixed order of succession as in most pleomorphic Uredinales. It is one of the
RMRDX1NC–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. n] ASCOMYCETES 47 four. Further the adhesion of chromosomes already described for Phyllac- tinia must not be forgotten. The occurrence of paired nuclei in the ascogenous hyphae was thus the most important evidence in favour of Claussen's view until in 1916 Welsford showed that the nuclei even of gametophytic, multinucleate hyphae are habitually paired if rapid growth and division are taking place; this is due to the fact that mitoses follow one another so rapidly that the daughter nuclei of any parti- cular division have not time to move
RMRE38C2–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. SPOROPHYTE (2n generation) uredospore secidiosppre intercalary cell GAMETOPHYTE (w generation). '^spermatium i gamete ¥ gametes fusion-cell The n generation is that in which the nucleus has the haploid number of chromosomes or, if there are no distinct chromosomes visible, the single amount of chromatin; in the 2?? generation each cell has the double (diploid) number of chromosomes or the double amount of chromatin, at first sur- rounded by two nuclear membranes, afterwards by one.. Please note that these image
RMRH1JHE–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. SPOKOPHYTE (2n generation) uredospore^ ascidiospore" intercalary cell' GAMETOPHYTE (n generation). spermatium $ gamete ? gametes fusion-cell The n generation is that in which the nucleus has the haploid number of chromosomes or, if there are no distinct chromosomes visible, the single amount of chromatin; in the 2/; generation each cell has the double (diploid) number of chromosomes or the double amount of chromatin, at first sur- rounded by two nuclear membranes, afterwards by one.. Pleas
RMRH1HTR–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON UMBELLIFER^: 191 between the two forms. Conium macxdatxim took the infection very weakly. Lindroth and Fischer both describe the teleutopores as furnished with nunaerous minvite embedded granules, otherwise even or with low rounded undulations, but Fischer figures them as perfectly smooth, as they certainly are in the cases I have seen. The uredospores are spiny in the upper part, nearly smooth below. When the few spines on the basal part are not to be discerned (as sometimes happens), they closely resemble
RMRE38CX–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. GERMINATION OF BASIDIOSPORES 15 If one of these easily detached basidiospores or conidia is conveyed to the surface of a leaf or young stem of Nettle, its germ-tube bores through the cuticle and enters the tissues (Fig, 17), where it ramifies and forms a my- celium. The teleutospore is large and heavy, and firmly attached to its spore-bed on the leaf of Gareoc; the basidiospores enable its con- tents to be transferred easily to ^^8- ^1-. Endophyllum Sem- â ' pervivi. (Terminating basi- the surface on which alon
RMRH1GKD–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. MELAMPSORA :;:>:! l>v looking in spring on fallen leaves of /'. tremula, /'. alba, at places where Mercurialis is found to be affected. The caeoma on the latter is very capricious in its occurrence ; in some years it may be found almost every- where, in other years hardly a specimen can be met with. The large yellow spots show conspicuously on the upper surface of the leaves, so that when it does occur it is impossible to overlook it. There are two places near Birmingham where all the spo
RMRH1JHN–. The British rust fungi (Uredinales), their biology and classification. Uredineae. GERMINATION OF BASIDIOSPORES 15 If one of these easily detached basidiospores or conidia is conveyed to the surface of a leaf or young stem of Nettle, its germ-tube bores through the cuticle and enters the tissues (Fig. 17), where it ramifies and forms a my- celium. The teleutospore is large and heavy, and firmly attached to its spore-bed on the leaf of Garex; the basidiospores enable its con- tents to be transferred easily to ^'^- l^-. Endophyllum Sem- â¢^ pervivi. Germmating basi- the surface on which alone t
RMRDX1HW–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. 70 PLECTOMYCETES [CH. the outer filaments form four or five parenchymatous layers which constitute a protective sheath, apparently differing but little from that of Eurotium or Penicillium. In the investigated species of the genus Eurotium (^Aspergillus), the ascospores and conidia are commonly multinucleate and give rise on ger- mination to a septate mycelium each cell of which contains several nuclei. Conidiophores appear early; they arise as a rule from densely tangled knots of swollen mycelium, and appear as thick, multinucleate hypha
RMRDTNBB–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] SPHAERIALES 157 long hairs around the ostiole, and from the Sphaeriaceae in the habitat and type of spore. The mycehum is in most cases composed of multinucleate cells, but in Podospora hirsuta the cells are uninucleate (fig. 115), recalling the condition in several species of Chaetomium. The commonest type of archicarp is a stout, coiled, septate hypha which soon becomes surrounded by vegetative filaments; it is usually terminal, but is occasionally intercalary, for instance in Sordaria fimicola. Dangeard has found a straight archicar
RMRDX0P1–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Fig. 170. Uromyces Poae'R&h&n.; aecidium just before the epidermis is broljen through, x 310; after Black- man and Fraser. Pliragmitis. A corresponding discoloration takes place around the young aecidia, and there is thus some suggestion that the spermatia, when functional, were carried to their destination by insects. The aecidia occur in groups, usually on the abaxial side of the leaf; in them the aecidiospores are produced in basipetal rows (fig. 170) alternating with small, abortive, intercalary cells, by the disintegration of
RMRDTP1W–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] PEZIZALES lOI Pyronemaceae The Pyronemaceae are a small group distinguished from the other Pezizales by the fact that the peridium, or lateral boundary of protective hyphae around the fruit, is not well developed. This is not always regarded as a sufficiently important character to warrant their separation from the Pezizaceae and many authors include them in that group. The only important genera are Ascodesrnis and Pyronema, species of both of which have been somewhat fully investigated. Ascodesrnis nigricans'' (fig. 59) is a small co
RMRDX143–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] LABOULBENIALES 173 monoecious forms) bears the appendages in a terminal position and the perithecium laterally (fig. 136). More rarely the receptacle consists of a larger number of cells variously arranged and reaching a considerable complexity in such forms as Zodio- myces vorticellarius (fig. 133). One or more appendages are borne on the receptacle. These are more or less filamentous and often elaborately branched. They bear the male organs and serve also for the protection of the delicate trichogyne and perhaps facilitate fertilizat
RMRH1JAN–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 40 GROUPS OF SPORE-FORMS The relations of the various groups to one another are represented in the following diagram. The circle represents the Eu-forras; the substitution of any one chord in the place of the arc which it subtends shows how the life-history is shortened in the other cases. Only the abnormal Endophyllum cannot be included in such a scheme ; its spore-grouping could only be represented by the symbol 0 yjjh- teleutospore uredospore -^ O uredospore basidium basidiospore. mycelium secidiospore fusio
RMRE3816–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. ON COMPOSITE 129 This genils occupies an intermediate position between Uromyces and the less advanced genera, Phragmidium, etc., as is shown by the fact that many species tend to form one-celled teleutospores (mesospores) indistinguishable from those of Uromyces, while others have spores with three or more cells, arranged as in Phragmidium, Triphragmium, Sphaerophrag- mium, etc. The number of species is enormous, more than 1300 are already known. The genus must therefore be subdivided, but no quite satisfactory
RMRH2XXY–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 78 PHYLOGENY are always, or usually, so placed. For instance, in Melam- psoridium betulinum the teleuto-sori almost invariably originate directly below the stomatal pore. The cause of this cannot be merely the need of oxygen for respiration, since it has been shown that the intercellular spaces of a leaf are all well supplied in that respect. Fig. 37 is drawn from the lower epidermis of a leaf of Betula alba in which teleuto-sori were just beginning to be produced. The same thing is true of the teleuto-sori of
RMRH1JJE–. The British rust fungi (Uredinales), their biology and classification. Uredineae. TELEUTOSPORES 11 both (Fig. 12). The uredospore retains its capacity for germination for a longer time, even for more than three months; in fact, in certain foreign species, some of these spores acquire a thicker wall which enables them to act as a kind of resting-spore—these are called amphi- spores, but they are not formed by P. Garicis. It is found, generally, that if the spores of the Uredinales are dried gradually, they retain their power of germination for a longer time and in a better degree than if drie
RMRH1JDW–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. TELEUTOSPORES 35 The teleutospores are generally produced in sori like those of the uredospores; they frequently arise on the same mycelium, and very often on the same spore-bed, mingled with the uredo- spores. If both are found in any species, the teleutospores are always formed at least not earlier, and usually later than the uredospores. Their primary function now is to tide over an unfavourable period; for this reason they are sometimes called, in England, winter-spores. They may be one-cel
RMRH2X8H–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 128 PUCCINIA Concerning the difference between this species and U. Dactylidis (apart from the habitat) httle that is definite can be said. Some authors unite them, but I find the teleutospores of U. Poae to be usually more oblong and often provided with shorter pedicels and the sori to be less conspicuous. The leaves of Foa are smaller than those of Dactylis, and the teleuto-sori do not cover them in such enormous numbers and never extend to the culms. Juel divides this species into 9 or 10 biological races, bu
RMRH2TM5–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 264 PUCCINIA membrane marked with about nine (7—10) germ-pores, which are each surromided by a httle thickening of the cell-wall, so that they look some- what like a " bordered pit" ; the teleuto-sori mostly on the lower leaf-surface or sheath, black, covered by the epidermis ; the teleutospores obconical or with nearly pai-allel sides, truncate, rounded, or pointed (obtusely and often obliquely) at the apex ; the slightly thickened apical wall and a broad band at the base chestnut-brown, but the rema
RMRDTNBX–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] SPHAERIALES iSS Chaetoniiaceae The Chaetomiaceae occur on straw, paper, dung and other waste materials; they possess free, thin-walled perithecia beset with numerous characteristic, long hairs (fig. 112), which are often elaborately branched or coiled. On these, or on the ordinary vegetative mycelium, conidia are produced. An ostiole is lacking in Ch. fimete, presumably the most primitive member of the genus; in the remaining species it is present and the peri- thecium is of the typical sphaeriaceous form. In Chaetomium spirale the cel
RMRDTP1D–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] PEZIZALES 103 oogonium, from which a trichogyne protruded (fig. 61 b). The union of the trichogyne and antheridium was observed and it was shown that from the oogonium ascogenous hyphae subsequently arose. Van Tieghem recorded that the species is very susceptible to external conditions, the antheridium sometimes being reduced in size or absent, though the oogonium nevertheless developed normally and produced ascogenous hyphae. In 1900 appeared the classical researches of Harper, followed in 1903 and 1907 by Dangeard's, and in 1912 by
RMRH2Y00–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 58 MELAMPSORA PINITORQUA point, combined with this lateral curvature, causes S-shaped distortions which have given rise to the name " Pine Branch Twist" for the disease (Fig. 35). It is suggested by Massee that the aecidiospores can repro- duce the ascidia and thus propagate the parasite on the Pine without reference to the alternate host, but no proof is given of this statement. The mycelium is almost certainly perennial in the affected branch, and thus fresh outbreaks arise year by year more or less
RMRH2RY8–. The British rust fungi (Uredinales), their biology and classification. Uredineae. CRONARTIUM 315 produce the same on Vincetoxicum, Ji'emesia, Cynanchum, and Verbena., as well as on many species of Paeonia. There is reason for believing that the parasitism on Xemesia, at least, has arisen at a very recent date. This species is therefore plurivorous in its teleuto-stage, but not in its secidial stage. The mycelium is perennial, according to Fischer, in the pine- branches ; it produces secidiosiaores in May and infects the alternate hosts, on which uredo- arid teleutospores are borne during the
RMRH1JJF–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. STERILE CELLS 19 Christman, occurring side by side. All the conjugating cells had an upper sterile cell which he calls a "buffer" cell; but the passage of the nucleus only he put down, as others have done, as a pathological phenomenon, caused perhaps by the method of fixing. In November of the same year Dittschlag, investigating Puccinia Falcariae, tried to settle the question and decide definitely the function of the spermatia. This Puccinia is an -opsis form, having spermogones and
RMRH1JDP–. The British rust fungi (Uredinales), their biology and classification. Uredineae. STERILE CELLS 19 Christman, occurring side by side. All the conjugating cells had an upper sterile cell which he calls a " bufifer" cell; but the passage of the nucleus only he put down, as others have done, as a pathological phenomenon, caused perhaps by the method of fixing. In November of the same year Dittschlag, investigating Puccinia Falcariae, tried to settle the question and decide definitely the function of the spermatia. This Puccinia is an -opsis form, having spermogones and a^cidia, follow
RMRH1JC0–. The British rust fungi (Uredinales), their biology and classification. Uredineae. SPOROPHYTE {2n generation) uredospore^ fecidiospore intercalar}' cell GAMETOPHYTE (n generation). spermatium <? gamete ? gametes fasion-cell The 7i generation is that in which the nucleus has the haploid number of chromosomes or, if there are no distinct chromosomes visible, the single amount of chromatin; in the 2?? generation each cell has the double (diploid) number of chromosomes or the double amount of chromatin, at first sur- rounded by two nuclear membranes, afterwards by one.. Please note that these
RMRDTNA8–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] SPHAERIALES 159 rotia which originate in the cortex of the host root; reproduction is by means of conidia formed in summer on the surface of the soil, and further by ascospores produced in perithecia. Hartig has found that the perithecium is initiated by the development of a pair of thick hyphae rich in contents. These become enclosed within a mass of vegetative tissue, but their subse- quent behaviour has not been determined, and no details of development are known either here or in other members of the family. SPHAERIACEAE : BIBLIOGR
RMRH2T9F–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. PHRAGMIDIUM 291 The uredospores of this species are distinguished from those of its allies by being densely and rather coarsely verruculose and very similar to the Cccoma-spores, from which, in fact, they differ almost solely in being abstricted singly and not in chains. The cseorna-stage is one of the earliest Uredines of spring, showing on the leaves as soon as they are well developed, and extending even to the calyx. The teleutospores are entirely devoid of papilla on the apical cell ; the g
RMRH2W49–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON LILIACE^: 233 Plowright observed that the spores would not germinate at once, but, by securing the affected leaves during the winter near some plants of JV. poeticus, he found the Puccinia reproduced next year and for eight or nine years afterwards, though only on the tips of the leaves. The reticulation of the spores varies in character, sometimes resolving itself into longitudinal ridges or rows of warts. Mesosporcs and other abnormal spores are recorded by Fischer. Distribution : Belgium, Italy, Carniola.
RMRE3792–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. ON LILIACE^: 233 Plowright observed that the spores would not germinate at once, but, by securing the affected leaves during the winter near some plants of N. poeticus, he found the Puocinia reproduced next year and for eight or nine years afterwards, though only on the tips of the leaves. The reticulation of the spores varies in character, sometimes resolving itself into longitudinal ridges or rows of warts. Mesospores and other abnormal spores are recorded by Fischer. Distribution : Belgium, Italy, Garniola.
RMRH2XA2–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. ON COMPOSITE 129 This genus occupies an intermediate position between , Uromyces and the less advanced genera, Phragmidiurn, etc., as is shown by the fact that many species tend to form one-celled teleutospores (mesospores) indistinguishable from those of Uromyces, while others have spores with three or more cells, arranged as in Phragmidiurn, Triphragmium, Sphaerophrag- iii ia m, etc. The number of species is enormous, more than 1300 are already known. The genus must therefore be subdivided, b
RMRDTNJ0–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] PHACIDIALES 133 of calcium oxalate; when the fruit opens it forms a white border around the hymenium. The pale colour, and the ragged or tppthed dehiscence of the sheath are very characteristic. Phacidiaceae The Phacidiaceae are distinguished by their black, thick-walled apothecia, usually scattered, sometimes, as in Rkytisma, grouped on a black stroma. Where the fertile disc is circular the sheath splits in a stellate manner, but where it is elongated, dehiscence takes place by means of a slit running along its entire length. The spe
RMRDX0JR–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. VIIl] UREDINALES 205 produce a second type of uredospore with thick walls which are adapted to survive unfavourable conditions; these are known as amphispores. Both aecidio- and uredospores germinate readily and without a rest if fully ripe, but many are shaken off by wind and rain before they reach maturity and remain incapable of germination. Moreover it is stated that spores will not ripen properly on leaves that have been removed from the plant. Sooner or later the mycelium of binucleate cells gives rise to teleuto- spores; these are
RMRE1WPE–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 264 PUCCINIA membrane marked with about nine (7—10) germ-pores, which are each surrounded by a little thickening of the cell-wall, so that they look some- what like a " bordered pit" ; the teleuto-soi'i mostly on the lower leaf-surface or sheath, black, covered by the epidermis ; the teleutospores oboonical or with nearly parallel sides, truncate, rounded, or pointed (obtusely and often obliquely) at the apex ; the slightly thickened apical wall and a broad band at the base chestnut-brown, but the rem
RMRH2Y0B–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 56 CRONARTIUM RIBICOLA of Rihes (Fig. 34); they have been recorded on 26 out of about 50 known species. The spermogones and aecidia are formed on stems and branches of the five-leaved species of Pinus: they have been found on five out of the eighteen Pines of that group, but do not attack species having 2 or 3 leaves in a fascicle. The following account is founded on that of Spaulding (1911). The basidiospores are formed about the beginning of August, and if they are blown by the wind, and adhere to moist young
RMRDX1P8–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Ill ASCOMYCETES 45 was proposed. The occurrence of a brachymeiotic reduction has since been observed in several other fungi, and has also been in several cases denied. Chromosome Association. There are a number of fungi, of which Phyllactinia Corylea is perhaps the most fully studied, in which no change in the chromosome number takes place throughout the life-history. In Phyl- lactinia, Harper showed in 1905 that the chromosomes remain visible in strands attached to the central body throughout the resting stages. In each of the nuclei of
RMRE58RX–. Cryptogamic plants of the USSR. (Flora sporovykh rastenii SSSR). Plants. 48 the basidiospores from the germinating teliospores infect pine leaves, on which aecia are produced in the following spring. In all these fungi, in addition to those producing either several generations per year, or one (as in Gymnosporangium, Coleosporium, Cronartium, Milesia, Hyalopsora, Melampsorella), or two (as in Chrysomyxa), the hosts are represented by evergreen plants, while in Micro-Uredinales with one generation of teliospores the mycelium overwinters in the evergreen leaves or overwintering buds. In some r
RMRH2R5F–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. UREDINOPSIS 379 UREDINOPSIS M; iio-nus. Teleutospores solitary, extracellular, hyaline, septate. Uredo- sori subepidermal, with a distinct peridium; ureclospores hyaline, pedicellate, without germ-pores. On Ferns. This genus is distinguished from all others by the fact that the teleutospores are dispersed without order among the cells of the mesophyll. There are three known forms of spores, which seem to occur simultaneously, and not in a fixed order of succession as in most pleomorphic Uredina
RMRDTNFP–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. CHAPTER V PYRENOMYCETES The Pyrenomycetes include some 10,000 species; they are characterized by the fact that their ascocarp or perithecium is a more or less flask-shaped organ opening by a narrow pore, the ostiole, and containing a hymenium spread in a regular manner over the floor and lower part ofthesides (fig. 100). It thus differs from the perithecium of the higher Plectascales where the asci are irregularly scat- tered, and from that of the Erysiphales where, except in the flattened perithecium of the Microthyriaceae, an ostiole is
RMRH28TK–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. 14 GERMINATION OF TELEUTosi'ultKs Ckhmixation of the Teleutospoee. We ii" approach the consideratioD of a process which has been in the past much discussed, and upon the right inter- pretation of which the whole question of the systemal ic p« >>ition of the l/redinales depends. Kadi cell of tin- teleutospore of P. Caricis has one germ-pore, though some genera allied to Puccinia have toleutospores with more than one germ-pore to each cell, e.g. Phragmidium, Uropyads, Calliospora. Th
RMRE37G0–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 192 PUCCINIA This species was included by Sydow under the old P. bullata of Winter ; but since then it has been rendered probable by the experiments of Semadeni that it is distinct from most of the forms still remaining under that collective name (Centralbl. f. Bakter. 1904, 2. xiii. 530). Schroter proved that the spore-forms described above are genetically connected. The uredo- and teleutospores are generally found intermixed. 64. Puccinia Angelicae Fckl. Uredo Angelicas Sohum. PI. Sail. ii. 233. Trichohasis A
RMRH1JBH–. The British rust fungi (Uredinales), their biology and classification. Uredineae. TELEUTOSPORES 35 The teleutospores are generally produced in sori like those of the uredospores ; they frequently arise on the same mycelium, and very often on the same spore-bed, mingled with the uredo- spores. If both are found in any species, the teleutospores are always formed at least not earlier, and usually later than the uredospores. Their primary function now is to tide over an unfavourable period; for this reason they are sometimes called, in England, winter-SY>ores. They may be one-celled as in. F
RMRDX1TR–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. n] ASCOMYCETES 39 (i-«-.. hymenium. In Desmotascus^, a pyrenomycetous fungus parasitic on Bromelia, the paraphyses are replaced by a thin-walled pseudoparenchyma recalling the arrangement in the higher Plectomycetes. The Peridium. The peridium or wall of the ascocarp is a weft of sterile hyphae in which the individual filamentsare sometimes clear- '^- ly distinguished, sometimes closely interwoven to form a pseudoparenchyma; the walls of the outer cells are some- times considerably thickened and may be variously pig- mented ; in many case
RMRE38AG–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. PUCCINIA POARUM 47 as shown in radial section. Tiie outer edge of each cell is more prolonged downwards so as to overlap a portion of the cell below in an imbricated manner. The secidium, in both, as is the. 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 may not perfectly resemble the original work.. Grove, W. B. (William Bywater), 1848-1938. Cambridge, University Press
RMREF7BA–. Comparative morphology of Fungi. Fungi. PEZIZALES 325 the obligate manner we shall find in the Uredinales. While in the latter the host change is connected with a change of nuclear phase, is condi- tioned in its rhythm by plasmogamy and meiosis, and, besides, usually takes place between two hosts far removed systematically; in Sclerotinia and Claviceps we are dealing with plurivorous forms which have been specialized on seasonal hosts. The economically important representatives of the subgenus Eusclero- tinia, as S. Fuckeliana, S. Libertiana, S. Trifoliorum and the various Sclerotinias on mo
RMRE38EE–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. SPERMOGONES The mycelium in the leaf is strictly localised, forming little knotted masses (jplectenchyma) just beneath the epidermal cells of th6 affected spot; all the cells of this mycelium are uninucleate. Some of these hyphse turn upwards, remaining densely crowded and more or less parallel to one another, and enclose the flask-shaped cavity, at length converging to a point above it and piercing the epidermis at that place. Then the upper ends of these hyphse diverge and form a brush-like bundle surrounding
RMRH1HT7–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 192 PUCCINIA This species was included by Sydow under the old P. hullata of Winter ; but since then it has been rendered probable by the experiments of Semadeni that it is distinct from most of the forms still remaining under that collective name (Centralbl. f. Bakter. 1904, 2. xiii. 530). Schroter proved that the spore-forms described above are genetically connected. The uredo- and teleutospores are generally found intermixed. 64. Puccinia Angelicae Fckl. Uredo Angelicae Schum. PI. Sail. ii. 233. Trichohasis A
RMRDTP33–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. 96 DISCOMYCETES [CH. the sides and bottom of the cup. In many cases, as in Pesiza vesiculosa and Otidea aurantia, the cup is small and comparatively full when it first opens, and grows larger and deeper as development proceeds.. 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 may not perfectly resemble the original work.. Gwynne-Vaughan, Helen Charlotte Isabella (Fraser) Dame, 1879-. Cambridge [Eng] University Pres
RMRH2X6C–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON COMPOSITE 133 been found (Gibson, 1904, p. 188). If that is so, the disease can easih- be kept in check by rigid cleanhness and by spraying at intervals with very dihite Bordeaux mixture or, better still, potassium sulphide solution. Remove and burn all attacked leaves as soon as seen, water carefully with- out wetting the leaves, choose resistant varieties {e.g. " October Sun " and " William Tricker" are said to be immune), and there will be little fear of an epidemic of the disease. Dis
RMRH2Y2E–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 52 GYMNOSPORANGIUM CLAVARI^FORME sterigmata, much in the same way in which the basidiospores are thrown off in the Agaricini^ They accumulate in large numbers on the outside of the mucilaginous mass, and present the appearance of a golden-yellow powder. The mycelium of the fungus is perennial in the Juniper, spreading from branch to branch and producing a fresh crop of teleutospores each spring. If one of the basidiospores is blown by the wind or carried by insects to a moist leaf or young fruit or stem of Hawt
RMRH2X88–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON COMPOSIT.E 129 This genus occupies an intermediate position between Uromyces and the less advanced genera, Pliragmidium, etc., as is shown by the fact that many species tend to form one-celled teleutospores (mesospores) indistinguishable from those of Uromyces, while others have spores with three or more cells, arranged as in Phragmidiiim, Triphragmuim, Sphaerophrag- mium, etc. The number of species is enormous, more than 1300 are already known. The genus must therefore be subdivided, but no quite satisfacto
RMRDX151–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] LABOULBENIALES 171 LABOULBENIALES The group Laboulbeniales includes some six hundred species arranged in over fifty genera. All are minute external parasites on insects, chiefly on members of the Coleoptera. They appear to do but little injury to the host, inducing at most a slight irritation but never causing death; indeed their own existence depends on that of the insect to which they are attached since, unlike many other fungi, their life ends with that of their host. The Laboulbeniales are all of fairly simple structure (fig. 130)
RMRDX127–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. 178 PYRENOMYCETES [CH. 5". There is an obvious suggestion in these phenomena of a transition between the monoecious and dioecious condition but it is not clear in which direction the series should be read. It might be inferred that the male plant had become atro- phied after the female had acquired spermatial organs, or on the other hand that, as in many other groups of plants, a hermaphrodite con- dition was primitive and segregation a later development. Ainorphomyces Falagriae may be taken as an example of a dioecious form which sh
RMRDTNA1–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] SPHAERIALES i6i Pleosporaceae The Pleosporaceae are saprophytes or in a few cases parasites, for the most part on seed plants but in some cases on Pteridophyta, Bryophyta or Lichens. The perithecia are immersed in the substratum, the ostiole only projecting, but they may become more or less exposed by the rupture of the covering tissues. The peridium is leathery or membranous. The genus Pleospora includes some 225 species, several of which occur on grains and other grasses where they show biological specialization. Pleospora herbarum i
RMRDTNG4–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] TUBERALES 137 Bucholtz was able to examine, showed a system of internal chambers lined by the hymenium and communi- cating at one or more points with the exterior. As development pro- ceeds these cavities increase in size and the hymenium becomes further convoluted, so that additional cham- bers are formed. In Tuber the ascocarp is ir- regularly globose, fleshy or some- times almost woody; internally the walls which divide the gleba are extensively branched, and the free space between them is diminished, so that the layers of the hyme
RMRDTP5N–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. ERYSIPHALES 85 III] The antheridial branch is much narrower; it applies itself to the side of the oogonium and when first cut off contains a single nucleus (fig. 41 a). It is clearly differentiated from the hyphae of the sheath not only by its form and behaviour but by its much earlier appearance and definite relation to the oogonium. Its nucleus soon divides ; one of the daughter nuclei passes to the apex of the branch and a wall is formed cutting off the uni- nucleate antheridium. The oogonial nucleus is rather larger than those of the
RMRE37WX–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 146 PUCCINIA these latter that new infections arise in the spring as soon as the shoots appear. The hibernation of the mycelium in the rhizome, which is stated by Plowright, has not been proved. The germ-pores are very easy to see in the uredospores of this species and its allies. Each is often surrounded by a border like a bordered pit, an appearance caused by a thickening of the membrane around and over the pit. As usual the appearance of the spore changes according as it is wet or dry ; if wet, it may appear
RMRH2TFP–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON GRAMINE.'}>: 273 It was Plovvright who first proved, by a long series of cultures, that the ieoidium of this species is produced only on the two species of Ranunculus given above; Klebahn and Fischer have since abundantly confirmed his results. The recidia belonging to Uromyces Poae and U. Dactylidis occur on the same hosts and are morphologically quite indistinguishable, but begin to apfioar earlier in the sj)ring. P. Magnusiana is distinguished from the two following species by its numerous small teleut
RMRDX0XN–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. VIl] USTILAGINALES 187 In the regions where the formation of brand-spores is to take place, the mycehum becomes richly branched and often swollen and gelatinous. In Ustilago and Sphacelotheca the sporogenous hyphae are divided into a number of short segments in each of which the contents form a spore surrounded by an independent membrane. The spores are enclosed at first within the gelatinous parent walls, but later these disappear so that the whole mycelium is transformed into a pulverulent mass of spores. In Tilletia and Entyloma the sp
RMRDX10E–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. CH. VIl] USTILAGI'NALES i8s The mature brand-spore is uninucleate, and is surrounded by a delicate endospore and by an epispore which may be smooth or variously sculptured and usually contains pigment, giving the spore a black, brown, or violet colour. On germination the spore gives rise to a short tube, the promycelium or basidium (fig. 147), into which its contents pass, the nucleus undergoing at. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and a
RMRDX1PN–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. "] ASCOMYCETES 43 continuation of the ascogenous hypha, and gives rise to fresh asci (fig. lo). This process was first recorded in 1908 for Humaria rtttilans and has since been observed by McCubbin in Helvella elastica, by Carruthers in Helvetia crispa, and by Claussen in Pyronema confliiens. It suggests either that some advantage is to be derived from an absence of relationship between the nuclei which fuse in the ascus, or that a scheme of rigid nuclear economy is in force. The former hypothesis is somewhat weakened by the fact tha
RMRH1H8E–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON POLYGONACE^ 223 scattered singly : those of the Puccinia are in largish orbicular clusters and are rarely found singly ; if not clustered, they spread over the whole leaf. In Plowright's herbarium are some leaves of Lychnis diur/ui, covered with uredo-sori, which he mistakenly assigned to P. Lychnidearum : there are no teleutospores of the latter, however, but a very few of F. Behenis were found in the same sori. See under P. Lychnidearum. The circinate arrangement of the sori, on paler spots, is very simila
RMRE381A–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 128 PUCCINIA. Concerning the difference between tliis species and U. Dactt/lidis (apart from the habitat) little that is definite can be said. Some authors unite them, but I find the teleutospores of U. Poae to be usually more oblong and often pro'ided with shorter pedicels and the sori to be less consiiicuous. The leaves of Pon are smaller than those of Dtirti/lis, and the telcuto-sori do not cover them in such enormous numbei's and never extend to the culms. .Juel divides this sjiecies into 9 or 10 biologica
RMRH1HX1–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. ON UMBELLIFERjE 191 between the two forms. Conium maculatum took the infection very weakly. Lindroth and Fischer both describe the teleutopores as furnished with numerous minute embedded granules, otherwise even or with low rounded undulations, but Fischer figures them as perfectly smooth, as they certainly are in the cases I have seen. The uredospores are spiny in the upper part, nearly smooth below. When the few spines on the basal part are not to be discerned (as sometimes happens), they clo
RMREF635–. Comparative morphology of Fungi. Fungi. UREDINALES 561 (Poirault, 1913, 1915) and of PucciniaPruni-spinosae (Kursanov, 1914), a layer of palisade cells is normally formed at the base of the aecia. This layer occasionally may cut off a few sterile cells. Although these are still uninucleate, they proceed without apparent cause to differentiate aeciospore mother cells which appear entirely similar to the binucleate ones and, like these, divide into aeciospores and intercalary spores. The aeciospores are naturally uninucleate, i.e., the whole course of development proceeds parthenogenetically.
RMRDTNHP–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] TUBERALES 135 TUBERALES The Tuberales are typically subterranean though some species are only imperfectly buried, or grow among decaying leaves. When mature the fruits emit a powerful odour by which rodents are apprised of their where- abouts. The ascocarp is eaten and the spores dispersed after passing through the alimentary canal of the animal. The ascocarp is more or less globose, sometimes completely closed, sometimes with a small opening. The hymenium may form a smooth lining to the fruit or may be thrown into elaborate folds so
RMRE37P1–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 168 PUCCINIA the fusiform shape, thin walls, and pale colour of the teleutospores, which often become totally devoid of thickening at the apex, by the dropping off of the pale thickening cap, on germination. P. punctata is additionally distinguished by the presence of the seoidium. Fischer explains the fact, that distortions more usually accompany P. Valantiae, by the consideration that infection takes place from the basidiospores mainly through the cuticle of young and still growing parts, while teleuto-sori o
RMRH2XN2–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 98 UROMYCES part of the world; reported on many Leguminosse, but doubtless some of these are distinct species. Jordi has distinguished under U. Fabae three. Fig. 50. U. Fabae. 'I'eleutospores and uredospore on Vicia Cnicca.. 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 may not perfectly resemble the original work.. Grove, William Bywater. Cambridge, Univ. Press
RMRDTP0X–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] PEZIZALES 105 While the formation of the pore is in progress the nuclei of the tricho- gyne degenerate, and, by the time that they are completely disorganized, a migration of the male nuclei through the pore begins. Ultimately the contents of the trichogyne degenerate still further, till the cytoplasm and nuclei together form a densely staining mass which may be recognized even in the mature fruit. The male nuclei continue to pass into the tube until it is densely filled, and sometimes a trifle swollen. According to most observers the
RMRDTNPB–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] PEZIZALES "7 as twenty (Dodge), sometimes a much smaller number of cells. These are at first uninucleate (Harper, Welsford), or multinucleate (Dangeard); later they always contain numerous nuclei (fig. 76 a). One of them, usually the. 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 may not perfectly resemble the original work.. Gwynne-Vaughan, Helen Charlotte Isabella (Fraser) Dame, 1879-. Cambridge [Eng]
RMRDX11R–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Fig. 143. Amorphomyces FalagriaeT'3.yite'c; male and female individuals; a. young, b. mature; after Thaxter. Walls cut off the upper and the lower nucleus, and a central binucleate cell is left, the lower nucleus of which is presumably a daughter of the oogonial and the upper of the trichophoric nucleus. These divide simultaneously and a binucleate inferior sterile cell is separated from the binucleate fertile cell. This in turn divides to form the ascogenic cells, from which the asci are to develop, and these and the asci which they pr
RMRE370G–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 300 KUEHNEOLA several cells as in Phragmidium, but the wall is faintly coloured or colourless, and smooth; pores one in each cell, apical. This genas is not confined to Rosacese, being recorded on Malvaceae in America, where also both the British species are found. It is not closely allied to Phragmidium: the wall of the teleutospores and the germ-pores are quite different. But I" am also of the opinion that the two species included here are not in reality congeneric. 1. Kuehneola albida Magnus. Uredo Midl
RMRH2RWY–. The British rust fungi (Uredinales), their biology and classification. Uredineae. Fig. 241. C. Senecionis. a, chain of uredospores; h, two fascicles of leaves of P. silvestris, bearing peridia on one leaf only of each fascicle (reduced). Fi£ '24:2. C. Senecionis. Teleuto- spore germinating. This is the species of Coleosporium whose life-historj has been longest known; "Wolff first experimentally demonstrated it in 1872, and he was followed by Plowright in 1882, as well as by Cprnu, Hartig, Rathay, Von Thiimen, Rostrup, Klebahn and Fischer. The aecidium had previously been called Perider
RMRH2RTJ–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 324 COLEOSPORIUM Uredospores. Sori scattered, orange, at first covered by the epidermis, soon pulverulent; spores ovate or ellipsoid, densely and evenly verruculose, 21â34 x 14â21 [x. Teleutospores. Sori forming little red crusts; spores pris- matic, length up to 100 fi, breadth 18â24yLi; epispore up to 14 yu, thick at the summit. ^cidia on leaves of Pinus silvestris; uredo- and teleutospores on Petasites officinalis, AugustâNovember, not uncommon. The life-cycle has been demonstrated by Fischer and Wagner for
RMRH2XDM–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. ON POLYGONACE.E 117 On the same host-plants is a Puccinia, which (in the absence of the teleutospores) can be distinguished only by the fact that the uredospores have two (rarely three) germ-pores and are adorned with few and distant spines. There is little doubt that many of the specimens recorded as U. Acetosae are really the uredospores of Puccinia Acetosae. Distribution : Germany, France, Sweden, Norway, Finland. 29. Uromyces Polygoni Fckl. JEcidium aviculariae Kze.; Cooke, Handb. p. 545; M
RMRDTNJG–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. IV] HELVELLALES 131 Geoglossaceae The Geoglossaceae grow usually in damp or moist situations such as low, wet woods and shady slopes. They occur on soil or on dead branches or leaves, and two species of Mitrula are parasitic on living moss. The family includes some eight genera of which five are British.. 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 may not perfectly resemble the original work.. Gwynne-Vaughan,
RMRH1H7P–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 22(5 PUCCINIA as regards Pol. viviparum Klebahn expresses doubts, but Semadeni was able successfully to infect that species with uredospores from Pol. Bistorta. The form on Pol. viviparum is here kept provisionally distinct, since the secidium on Angelica has not been found in Britain. Of the second group, P. mammillata, there are two biological races— (1) P. Mei-mammillata Semadeni, on Meum, and (2) P. Angelicae-mam- millata Klebtihn, on Angelica. Neither of these has been found in Britain. All the four of the
RMRDX0H3–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Fig. 186. Endofhyllum Setnpervivi'L&v.; spores giving rise to basidia; both after Hoffmann. (fig. 186); its two nuclei fuse (fig. 187), its contents are extruded as a pro- mycelium, two successive nuclear divisions occur, cross walls appear and four basidiospores are produced, which, in due course, give rise to a uninucleate mycelium. The sporophytic stage thus endures only from the fusion of the fertile cells until the germination of the spores which they produce. Incidentally these observations in the case of Kunkelia nitens have de
RMRH1GFD–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. MELAMPSORELLA 363 and vain scanh extending over many years; it has been confirmed by Tubeuf, Klebahn, and Bubak. The secidia of three other species, Melam- psorella Symphyti, Pucciniastrumpustulatum and Calyptospora Goeppertiana, which also live on the same host, do not cause any deformation of the shoots, and can therefore be easily distinguished. DISTRIBUTION : Europe, North America. 2. Melampsorella Symphyti Bubak. Uredo Symphyti DC. Encycl. viii. 232. Plowr. Ured. p. 255. Sacc. Syll. vii. 8
RMRH2XTT–. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. 92 IKOMVCKS the leaves. The mycelium of the secidial stage is said to be perennial in tin' host; Dietel says that in some Localities tin- secidiospores can re- produce themselves, and that then the uredo is suppressed. Both this species and the preceding are distinguished from U. flectens in the fad that tlu' sori are smaller, distributed more uniformly over the leaf, and do not ( ause distortions. The a M-id i i mi is ran- in I'.ritain (I have seen specimens only from Perth : most of our recor
RMRE38DB–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. TELEUTOSPORES 11 both (Fig. 12). The uredospore retains its capacity for germination for a longer time, even for more than three months; in fact, in certain foreign species, some of these spores acquire a thicker wall which enables them to act as a kind of resting-spore—these are called amphi- spores, but they are not formed by P Garicis. It is found, generally, that if the spores of the Uredinales are dried gradually, they retain their power of germination for a longer time and in a better degree than if dried
RMRDTNE3–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] HYPOCREALES 145 merit of the sheath has begun, may correspond to the septation of the fertihzed oogonium in other forms. Further, the origin of the asci from a single cell points to the Erysiphales and Laboulbeniales, and in view of the longitudinal divisions, perhaps especially to the latter. In Nectria the usually red or yellow perithecia are produced in groups on stromata of the same colour; the asci contain eight ascospores which are two- celled, and often produce conidia by budding while still in the ascus. The genus is large, inc
RMRH2XJE–. The British rust fungi (Uredinales), their biology and classification. Uredineae. 102 UROMYCES On leaves of Phaseolus vulgaris. May, July—October; even earlier on forced plants. Uncommon. (Fig. 55.) De Bary (I.e.) proved the genetic connection of the fecidia with the uredo- and teleutospores. The fecidia are rarely met with ; they may occur either before or in company with the other spore-forms. I have seen no proof that they have been found in this country. The description is founded upon that of Sydow. Fischer says that this species is very common in Switzerland on Phaseolus; it may become
RMRH2WR0–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON RUBIACE^. 167 On Galium Cruciata. Not uncommon. -July; teleutospores, August, September. Uredospores, May (Fig. 116.) Distinguished at once from P. Valantiae on the same host by the dark colour of its teleutospores, and their very great and dark apical thickening. The presence of uredospores also distinguishes them ; in P. Celakovskyana the two kinds of sori are often present together on the same leaf, the uredo-sori pale brown, and the teleuto-sori almost black. According to Bubak, almost its only distincti
RMRH2TWJ–. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON GKAMINEiE 251 often confluent and reaching a length of 1 cm. or more, surrounded by the cleft epidermis, pulverulent, yellow-brown : spores ellipsoid or ovate-oblong, echinulate, yellow-brown, then yellowish, 22—42 x 16—22 fx, generally with four equatorial germ-pores.. 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 may not perfectly resemble the original work.. Grove, William Bywate
RMRDX0WE–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Federley, in 1903, described specimens of this fungus in which conjugation is followed not only by the migration of the nucleus of one of the cells concerned, but also by nuclear fusion (fig. 15s). In view of the fusion in the young spore recorded by Dangeard and by Rawitscher the details of de- velopment in this species de- mand further investigation. Ustilago Maydis, the smut of Zea Mays, induces con- siderable hypertrophy. The deformations contain a mass of gelatinous mycelium from which brand-spores are produced. When mature, the spor
RMRDTP13–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. »--/. '@^..?>^^- Fig. 62. Pyronema confltiens a. antheridium, trichogyne and oogoniutiH- male and female nuclei collected in the middle of the latter; b. c. fusion of male and female nuclei; after Harper. spread out into the cytoplasm of the beak, suggesting that the solvent action is mainly exerted from the interior of the, trichogyne. The open pore now becomes thickened around its margin so that an exceedingly strong ring unites the antheridium and trichogyne, and they can be bent or turned upon each other without being pulled apar
RMRDX1RX–. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. cytoplasm forming the primordium of a;spore. In 1879 Schmitz observed nuclei in the vegetative cells of several Ascomycetes, and in 1893 Gjurasin in Peziza vesiculosa recognized that the divisions in the ascus are karyokinetic. The Fusion in the Ascus. In 1894, Dangeard showed in Peziza vesi- culosa and other forms with a well-developed fructification, that the ascus at its first inception is binucleate and that the two nuclei subsequently unite to form the definitive nucleus of de Bary.. He at first believed that the ascus was produced i
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