Introductory material is brief: there is an outline of the taxonomic problems surrounding the lichenicolous taxa assigned to these genera, most of whose species are not associated with lichens, as well as a history of the usage of these genera. This is followed by a fairly detailed discussion of the taxonomic characters and their value, the ecology and host specificity of the species treated in the revision.

The taxonomic part includes a survey of the orders in which the treated taxa are included, following the classification provided by Edn 8 of the Dictionary of the Fungi. A key is provided to all known non-lichenized lichenicolous fungi with a hyaline or dark pigmented excipulum and hyaline, aseptate ascospores. This does not include all the species covered in the work, e.g. Lichenochora aprica and Zwackhiomyces calcariae, for these are 1-septate; it also includes one genus, Sarcopyrenia, which is not mentioned again by the authors. A useful feature of the key is that significant characters are underlined. This is followed by accounts of the thirteen genera included: Biciliopsis, Guignardia, Gyrophthorus, Physalospora and Thamnogalla are covered briefly and the remainder are dealt with in more detail.

The first and unsurprising result is that neither Guignardia nor Physalospora is considered to contain any lichenicolous taxa: both these genera are more plant-pathogenic or found on substrata more typical of fungi. The lichenicolous species formerly assigned to these genera are now distributed across seven genera including one new to science, Telogalla. There is a useful discussion on the systematic position of the parasite of Thamnolia ­ Thamnogalla ­ which concludes that it seems closest to the Stictidaceae in the Ostropales. However, the authors do not propose this definitively. One of the longstanding uncertainties mentioned above is the genus Paralaestadia, for which the authors establish the correct author citation, `(Sacc. & D. Sacc.) Vain.' and typify it on Verrucaria verrucicola Wedd. This does, though, have a peculiar consequence in that this species was never formally combined into the genus Paralaestadia, but this is possible under the ICBN. The other consequence is that, based on the authors' examination of Verrucaria verrucicola Wedd., Paralaestadia is identical to Lichenochora and, as such, becomes an earlier synonym. They have rightly proposed the conservation of the latter name. The other species in Paralaestadia, P. fimbriatae Vain., is found to be identical to the coelomycete Lichenosticta alcicornaria, and thus the authors effectively dispose of any lingering doubts over the value of the genus.

The status of Obryzum and, up till now, its single species, O. corniculatum, has never been clear and it has been regarded as somewhat anomalous. In the present work not only is the genus accepted but a new species, O. friesii, is added and its distinctness confirmed by the retention of the family Obryzaceae. They reject Eriksson's view that the genus should be placed in the Gnomoniaceae since the asci of Obryzum lack the chitinoid ring in the ascus apex that is characteristic of the latter family. The genus Telogalla is here introduced for a gall-forming lichenicolous fungus that occurs on Xanthoria parietina. This is established for Guignardia olivieri and is placed in the Verrucariaceae, on the face of it, perhaps, an unexpected position but the hyaline exciple is, as the authors point out, not that unusual a feature in the family. Also unexpected is the transfer of one Physalospora species to Zwackhiomyces, a lichenicolous, dothidealean genus with 1-septate ascospores. HOFFMAN & HAFELLNER have broadened the definition of the genus to include species with aseptate (or usually aseptate) ascospores since in all other respects Physalospora lecanorae is consistent with Zwackhiomyces.

Even within the section on excluded taxa the surprises continue, with the lichenicolous `Laestadia' conductrix and `Laestadia' solorinae being transferred to Epibryon, a genus mainly containing bryicolous fungi. The detailed discussion associated with these species explains the biological and morphological reasons for these transfers.

The revision is completed with references and an index to taxa (not entirely complete as there is no entry for Spolverinia, for instance). It is well illustrated with some fine line-drawings and a set of micrographs of variable quality at the back. It should be said, however, that these are notoriously difficult organisms to section. As the title suggests, this work is entirely in German except for a summary in English, but because it is a valuable contribution, for those interested in lichenicolous fungi it is well worth making the effort to read it.

J.C. David

Bibliography of Systematic Mycology vol. 7