84 



Chlorophycece 





. 



/ 



branching soon becomes apparent. The zoogonidia in both 

 tophora and Myxonema (Stigeocloninm) frequently congregate in 

 masses on becoming quiescent and almost all germinate simul- 

 taneously (vide fig. 28 G). Palmelloid groups sometimes arise 



in Myxonema by the de- 

 generation of some of the 

 branches. Famintzin 1 and 

 Fritsch 2 have observed these 

 palmelloid cells germinate 

 directly to form new plants, 

 and Cienkowski 3 has seen 

 them give rise to microzoo- 

 gonidia, which latter form 

 the young plants. 



Akinetes( which are rest- 

 ing-cells or hypnocysts) are 

 frequently produced in all 

 the genera of this family. 

 In this condition of the plant 

 almost all the cells of a tuft 

 of branches take part in 

 spore-formation, one rest- 

 ing-spore being formed in 

 each cell. The original cell- 

 walls become hyaline or in- 

 distinct, causing the branch- 

 es to exhibit a moniliform 

 appearance. Each akinete 

 is of a red-brown colour with 

 a thick, asperulate cell-wall 

 (fig. 29 D). 



The gametes are small 

 biciliated bodies, practically 



Fig. 27. A and B, Chatophora incrassata indistinguishable from the 

 (Huds.) Hazen, from Scarborough Mere, 

 N. Yorks.; A, nat. size: B, x 500. C, Ch. 

 elegans (Roth) Ag., from Baildon, W. Yorks. 

 (nat. size). 



microzoogonidia except for 

 the possession of only two 

 cilia, and they conjugate in 



1 Famintzin in Melang. Biol. Bull. Acad. St Petersbourg, torn, viii, 1871, p. 265. 



2 Fritsch in Beihefte zum Botanischen Centralblatt, 1903, Bd xiii, Heft 4, 

 p. 384. 



3 Cienkowski in Botan. Zeitung, 1876, xxxiv. 



