ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 201 



Debarya immersa West.* — W. West finds that his recently de- 

 scribed species Mougeotia immersa must be transferred to the genus 

 Debarya. 



Conjugatse.f — Charles E. Bessey gives a short account of the struc- 

 ture and classification of this group with a revision of the families and 

 a rearrangement of the North American genera. He divides them into 

 three families, Zygnematacea?, Desmidiaceae, and Bacillariacea?, and gives 

 a key to these, and another to the genera of the Zygnemataceae. The 

 author regards the Conjugate as a degeneration from filamentous 

 algas of a higher type. Diagnoses are given of the genera iii Zygnema- 

 taceae. 



Fresh-water Alga? of the Royal Gardens, Kew.J — F. E. Fritsch 

 publishes a note on the periodical development of the algaj in the 

 artificial waters at Kew, and gives two tables illustrating the develop- 

 ment which takes place in a tank near the Jodrell Laboratory and in 

 the lake. He also remarks on the occurrence of certain species in the 

 hot-houses, where desmids and other Conjugata? are rare before April. 

 The hot-house flora is, however, more or less uniform throughout the 

 year, while the outside flora differs largely in summer and winter, 

 attaining its highest development in August and September. Desmids 

 are entirely absent in winter and are not very common in summer. 



Young Plants of Stigeoclonium. § — The same author has made a 

 minute study of the young plant of species of Stigeoclonium. After 

 giving an account of the results and views of other authors on this 

 subject, he proceeds to describe his own observations, worked out chiefly 

 on three species which are as distinct from each other as possible. 

 These are S. var labile Nag., S. nanum Kiitz., and a new variety, simplex, 

 of S.farctum Berthold. Under the heading of "The ordinary type of 

 young plant," the author describes the development of a plant from 

 the moment of the zoospore coming to rest. Species which have well- 

 developed hairs in maturity begin to form them very early in their 

 life-history, and the same may be said of the branching. The develop- 

 ment of the base varies according to the species, and plants occur in 

 which the young plant is attached by means of a specially modified 

 basal cell aided by rhizoids. These rhizoids may arise from the basal 

 cell or from the cells above it, and may become multicellular and very 

 long. A description is then given of S. farctum Berth, var. now 

 simplex, and comparisons are drawn between it and other epiphytic 

 species of the genus. The author believes that species of Herposteiron, 

 which possess distinctly septate hairs, are merely stages in the life- 

 history of species of Stigeoclonium. Finally, certain other forms be- 

 longing to Endoderma are discussed, which are possibly connected with 

 Stigeoclonium. 



New Genus of Valoniaceae.|| — F. Heydrich describes and figures 

 a new marine alga from Kerama, Loochoo Islands, Japan, and he creates 



* Journ. of Bot., xli. (1903) p. 58; and xl. (1902) p. 144. 

 t Trans. Amer. Micr. Soc, xxiii. (19U2) pp. 145-50. 

 X Ann. of Bot., xvii. (1903) pp. 274-8. 

 § Bcih. z. Bot. Central!)]., xiii. (1903) pp. 368 -87 (2 pis.). 

 || Flora, xcii. (1903) pp. 97-101 (4 figs). 



