xxxii SCIENCE PROGRESS. 



whole, a feat only rendered possible by the extensive series of investigations carried out by the 

 author within the Tropics, to which the majority of the plants appear to be confined. 



Dr. Moller treats first of the Auricularia group, which is characterised by the transversely 

 septate basidia, and he points out their relationship to the Uredineoe through such forms as 

 Saccoblastia. He traces the evolution of the thallus from a mere encrusting form with scattered 

 basidia, such as occurs in the genus Stypinella, on to the more complete types exemplified in 

 Auricularia itself. Further, he finds in Pilacrella a prototype of the angiocarpic Pilacre, a 

 plant which has been rendered familiar to us by the classical treatise of Brefeld. And similarly 

 in the Tremellaceae, in which the basidia are divided vertically crosswise, he finds a corre- 

 sponding gradation of form from a simple type such as Stypella to the most complicated 

 species of Tremella. Furthermore, Pilacrella finds its analogue in Hyaloria, which is 

 practically a Pilacre with Tremelloid basidia. 



The two groups, Auriculariacese and Tremellaceae, are linked together by Sirobasidiutn, 

 in which, besides other peculiarities, the basidia are usually divided obliquelv by a septum. 

 But both the position and number of the septa may vary. 



Perhaps the most interesting generalisation in the book is that which emphasises the fact 

 that amongst the Protobasidiomycetes there occur all the type forms which are met with in the 

 Autobasidiomycetes, with the exception of that of the Agarics. It remains to be seen how far 

 this is the result of independent convergence. Dr. Moller strenuously opposes the assumption 

 of any direct phylogenetic relationship existing between the Proto- and Autobasidiomycetes, and 

 he follows, or perhaps even exceeds, Brefeld, in regarding the two divisions as constituting two 

 fundamentally distinct series. At the same time, it must be borne in mind that even amongst 

 the Tremellas themselves there exists some latitude in the degree of completeness with which 

 the septation of the basidia is carried out, and we are ourselves inclined to attach a good deal 

 less weight to this character than Moller appears to do. To attempt to draw a hard and fast 

 line of demarcation between the two groups of fungi on the strength of a single character, such 

 as the absence or presence of septa, appears to us to be a dangerous proceeding, and one which 

 savours rather too much of an o priori method. And this reflection obtrudes itself the more 

 strongly when we take some of the author's own instances into consideration ; for example, 

 it is solely on this character that Proto-mcrulius is severed from Meruliui (with which in every 

 other respect it closely corresponds), and is regarded as belonging to a different original stock, 

 — the resemblance, though striking, being merely one due to convergence. 



The author elaborates Brefeld's view that the basidium is nothing save a specialised 

 conidiophore which bears a definite number of spores. If, however, the recent conclusions drawn 

 from the study of the nuclei within the basidia turn out to be sound, this comparison may 

 require revision. 



A further series of observations on the formation of the conidia in the Protobasidio- 

 mycetes is of special interest. Dr. Moller finds that many of these plants (e.g.. Pilacrella) 

 possess two distinct forms of conidia occurring on the same mycelium. One of these, the 

 large form, germinates readily; the other, the small kind, with difficulty or not at all. This 

 discovery is of importance, since both amongst the Ascomycetes and the Uredineae a similar 

 dimorphism is common ; the small conidia have been in these groups mistaken for sexual cells, 

 but it is now generally admitted that this opinion was erroneous. 



It is quite impossible, within the limits of a short review, to do justice to Dr. Moller's book 

 and to the plates and figures which accompany the text. It is emphatically a work which 

 everv one who is at all interested in Fungi should read for himself. 



The Structure of Man : An Index to his Past History. By Dr. R. Weidersheim, Professor in 

 the University of Freiburg. Translated by H. and M. Bernard. The translation 

 edited and annotated and a Preface written by G. B. Howes, F.L.S., Professor of 

 Zoology, Roval College of Science, London. London: Macmillan & Co. , 1895. 



In placing the above work before the English-reading public the translators have fulfilled 

 a useful task, for although, in spite of the short time it has been published, Professor Weiders- 

 heim's Der Bate der Menschen is already widely and favourably known amongst scientific 

 workers, vet a large class to whom the present translation will be of great use are debarred 

 from referring to the original by the fact of its being in the German language. 



The class which above all others will benefit by the publication of an English translation 

 embraces the vounger human anatomists, to whom only too often the learning of the dry- 

 details of the structure of man proves uninteresting in the extreme, chiefly because as at present 

 taught such details appear merely as a long array of facts without obvious connection, and 



