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Mycologia 



fully as to their life history, prevention, etc. Finally, he con- 

 siders them from the systematic point of view, and classifies and 

 describes the sixty-eight species, under ten genera, that have been 

 reported for Australia. An extended bibliography of smuts in 

 general, together with host, species and general indices, completes 

 the work. 



Regarding the origin of the smuts, after discussing the opinions 

 of others, he says : " My own idea is that the Ustilagineae may be 

 simply regarded as forms which have a distinct alternation of a 

 saprophytic with a parasitic stage, and with sexuality grafted 

 onto this, they originated the Uredineae. It is considered that 

 the promycelium bearing the conidia is a saprophyte, because it 

 generally grows freely in a nutritive solution." 



Regarding his characterization of genera, as exemplified largely 

 by the species included, there is room for a decided difference of 

 opinion. Personally, the writer would not make Cintractia em- 

 brace such a variety of species as he has done, since if we include 

 all species that have a more or less radial development of spores, 

 we would hardly know where to stop. We also believe that the 

 false membrane of sterile fungous cells enclosing the spore mass, 

 as indicated by the genus Sphacelotheca, is of generic importance, 

 a genus, however, that he fails to recognize in his classification. 

 Sorosporium Reilianum under its new generic position is appar- 

 ently no more happily placed than it was in its previous expe- 

 rience under Ustilago, Cintractia, or Sphacelotheca, since the 

 spore-balls at best are very vague affairs. However, it is an easy 

 matter to criticise the opinions of others when they differ from 

 our own. If we were all to agree on generic and specific char- 

 acters, the " natural " system of classification would have been 

 here long ago, which is merely another way of stating that it never 

 will come. 



In the matter of illustration, this monograph is well supplied 

 with excellent photomicrographs of the spores. — G. P. Clinton. 



