ZOOLOGY AND BOTANY, MICBOSCOPY, ETC. 285 



Sexuality in tlie Zygnemacess.* — Mr. F. Bates objects to Mr. A. W. 

 Bennett's views j as to the existence of characters whereby the sexual 

 nature of the filaments in the Zygnemacefe may be determined. 



The pajDer was apparently written in so reprehensible a style, 

 that the President of the Club, Dr. Carpenter, C.B., felt obliged to 

 suggest I that " there should be some modification of the language 

 employed by the author," as " there could be no reason why one 

 scientific man should in this manner impute motives to another. 

 No good ever came of it, and he was quite sure that their Journal 

 would be better without it." The recommendation was apparently 

 received with approval by the meeting, the President stating that 

 "he was glad to find that the feeling of the meeting was with 

 him in expressing himself on this matter." 



Parthenogenesis in Spirogyra.§ — L. Kolderup Eosenvinge de- 

 scribes a new species of Sj)irogyra, S. groenlandica, found among the 

 material collected by Fries in Greenland in 1871, in which partheno- 

 genesis frequently occurs. The parthenospores are sometimes formed 

 in the male cells, and are rather thin, but coloured ; occasionally 

 even when a male and female cell unite by lateral conjugation. In 

 these cases the contents of the female pass over into the male cell, a 

 portion sometimes remaining behind in the female cell, which then 

 developes into a parthenospore, while the male cell tindergoes no 

 further development. On the other hand, it also occurs that the 

 male cells develope into parthenospores. 



Geminella interrnpta,|| — E. Wollny describes this minute green 

 organism, which he finds abundantly in a ditch. He does not agree 

 with Kiitzing's reference of it to the Desmidieas, but considers it more 

 nearly allied to the Palmellaceae. The phenomenon which Kiitzing 

 regarded as an indication of conjugation, he looks on rather as the 

 result of rapid cell-division. Geminella interrupta shows greaJLre- 

 semblance to Hor-mospora, and is probably identical with H. minor ; 

 but Wollny would retain the former name for the organism, since the 

 genus Hormospora is a very ill-defined one, and the species H. minor 

 should probably be removed from it. Eesting-spores are formed by 

 the breaking-up of the filaments. 



Lithoderma fontanum, a New Fresh-water Phseospore.lT — C. 



Flahault describes a new species of fresh-water alga belonging to the 

 Pheeosporefe found in a small stream near Montpellier. It belongs 

 to Areschoug's genus Lithoderma, of which one marine and one fresh- 

 water species are already known, grouped in the family Ealfsiacese, 

 and very near in structure to Ralfsia. L. fontanum is considerably 

 larger in size than the other fresh- water species L. fluviatile, forming 



' Journ. Quek. Micr. Club, ii. (1885) pp. 104-8. 



t See this Journal, iv. (1884) p. 434. 



X Journ. Quek. Micr. Club, ii. (1885) p. 120. 



§ Ofvers. K. Svenska Vetensk. Forhaiidl., 1883, pp. 37-47 (1 pi.). See Bot. 

 Centralbl., sx. (1884) p. 165. 



II Hedwigia, xxiii. (1884) pp. 137-42 (l pL). 



\ Bull. Soc. Bot. France, xxx. (1883) pp. cii.-vi. (1 pi.). 



