566 SUMMARY OF CURRENT RESEARCHBS RELATING TO 



attachment to the host and a means of absorbing such materials as are 

 necessary for growth. Thaxter holds that the food-material is obtained 

 directly from the circulatory system of the insect. The new fungi de- 

 scribed are — Hormiscium myrmecophilum ; Muiogone (new genus near to 

 Sporidesmium), with one species ; Muiaria (new genus closely resembling 

 certain types of Macrosporium), with four species ; Chantransiopsis (a 

 Hyphomycete), with three species ; and Amphoromorpha, of uncertain 

 position but apparently corresponding most closely to some of the 

 Mycochytridinese : one species is described. 



Sexuality of Tilletia Tritici.* — F. Rawitscher has continued his 

 researches on the Ustilagineae. Previous observers have noted that there 

 is a fusion of nuclei in the brand-spore. Rawitscher germinated the 

 spores of Tilletia Tritici and T. I see is in water and infected young wheat- 

 plants with them. The germ-tube produced by the spores is long ; 

 the contents of the spore pass into it immediately. In all cases the 

 germ-tube contains eight nuclei. It is assumed that a reduction- 

 division occurs when the original spore nucleus divides, but the eight- 

 nucleate stage was the earliest observed. Usually eight sporidia are 

 produced on the end of the germ-tube, though frequently teu, twelve, 

 or sixteen are formed. Each receives a single nucleus from the tube. 

 The sporidia then build the well-known copulation tubes. The nucleus 

 of the one sporidium passes over through the tube, and from the result- 

 ing binucleate sporidium long hyphas grow out, which are also bi- 

 nucleate, and can produce binucleate secondary sporidia. The infection 

 of young wheat-plants takes place by means of such a binucleate hypha. 

 The production of brand-spores was not followed owing to the failure 

 of the author's wheat-cultures. The course of events is apparently 

 similar to that recorded by Rawitscher for Ustilago carlo. Some in- 

 teresting remarks are made concerning the constant appearance of an 

 eight-nucleate stage in the germ-tube, the number recalling the forma- 

 tion of asci, and the method of spore-production recalling that of basidia. 



Sori and Mycelium of Rusts in the Carycpses of Cereals.f — J' 

 Eriksson points out, in reference to Beauverie's observations on the 

 presence of the sori and mycelium of rusts in the caryopses of cereals 

 and other Graminea?, that he had already described and figured this in 

 1896. In 1901 he expressed the opinion that such are to be regarded 

 as an abnormal and excessive growth, having no practical importance in 

 the life of the fungus. In 1912 he gave his results on the wintering 

 of cereal rusts, and recent observations have confirmed the opinion that 

 the presence of mycelium and clusters of spores on the surface of the 

 caryopses is without importance ; similar observations have been pub- 

 lished by Pritchard in the United States. 



Mycena.J — J. E. Lange begins his Studies in the Agarics of Den- 

 mark by a consideration of the genus Mycena. There is a general intro- 

 duction to Agarics in general. It is pointed out how it is universally 



* Ber. Deutsch. Bot. Gesell., xxxii. (1914) pp. 310-14. 

 t Comptes Rendus, clviii. (1914) pp. 1194-6. 

 X Dansk Bot. Ark., i. (1914) pp. 1-40 (2 pis.). 



