248 THE JOURNAL OK BOTANY 



teaches that a prolonged resting conditiou is no argument for or 

 against a morphological dividing line in life-history. But my 

 colleague Mr. V. H. Blackman, who has kindly looked through the 

 book with me, seems to favour this putting back of the gametophyte 

 stage. In their account of the male gametophyte in the Cycads, 

 the authors point out that the relation between the ciliated sperm- 

 cells of the Cycads and those of the Fern-plants is rather biological 

 than morphological, as each corresponds to the mother-cell of 

 a fern antherozoid and not to the ciliated male cell. They are 

 therefore identical with the so-called male cells of all ordinary seed- 

 plants, being peculiar only in the possession of cilia. The contrast 

 with Pterodophytes, where each mother-cell organises and dis- 

 charges a ciliated sperm-cell, is a sharp one. 



The bibliography at the end of each chapter is useful ; we are, 

 however, surprised to find no reference to Dr. Masters's work on 

 the morphology and taxonomy of the Criiciferm. 



We regret that we can give no information as to the price of the 

 book, the more so as it is one which the advanced student should 

 read. It is difficult to understand the extreme modesty of some 

 publishers in refraining from obtruding the price of a book on the 



'''''^'''- A. B. E. 



Recent American Papers on Fungi. 



In America, even more than in this country, cultivated plants 

 are subject to epidemics of disease caused by parasitic fungi. An 

 account of one of these pests that attacks the violet has been pub- 

 lished by Mr. P.H.DorsettinBulletinNo.23 of the U.S. Department 

 of Agriculture. The violet disease is due to a hyphomycetous fungus, 

 Alternaria ViolcE. The plants are attacked on any part and at any 

 stage, but it is the growing leaves that suffer most. They are much 

 disfigured by the spots and blotches caused by the fungus, and often 

 entirely killed. The disease has in many places seriously checked 

 the culture of violets. Mr. Dorsett suggests preventive measures, 

 as fungicides are found to be ineffective. The illustrations from 

 photographs are very good. 



Dr. Herman von Schrenk published last year a report on some 

 of the fungi that grow on red cedar, Juniperiis virginiana ; he has 

 recently issued in Bulletin 25 the preliminary results of his studies 

 on some of the diseases of New England conifers caused by fungi 

 of the group of PohjporecE. Most of them are well-known enemies 

 of European foresters, but in the great untended woods of America 

 they work more damage than they are allowed to do here. One of 

 the most troublesome and the most difficult to stamp out is Polij- 

 poras Schweiiiitzii, which fastens on the roots, and spreads under- 

 ground from tree to tree ; the fruiting bodies are at first produced 

 on the ground, and finally on the trunk of the tree. The other 

 members of the group that he describes — P. j^micola, Trametes 

 Pini, &c. — are wound parasites ; they gain entrance by broken 

 branches, or through the holes caused by insects and woodpeckers. 

 Where conditions are favourable to their growth, they very soon 



