ZYGNEMA. 153 



broad, spires numerous, granules small. Sporangia 

 hroadhj oval, sometimes almost circular, lying obliquely 

 in the cells, ichich are not iiiflated. 



Z. ro stratum Ilassall, MSS. 



Ilab. Pond, near Ilounslow : A. H. H, 



A very fine species, the largest of all the non-conjugating 

 Zygnemata. It is very rare, for I have only once encoun- 

 tered it. 



28. Zygnema Woodsii Hass. 

 Plate XXXIII. Fig.J. 



Char. Filaments of somewhat less diameter than those of 

 Zygnema quininum. Cells usually about half or two- 

 thirds as long as broad. Sporangia oval, lying obliquely 

 in the cells, which are enlarged on that side from which 

 the tubes of communication proceed. 



Z. Woodsii Hassall, MSS. 



Hab. Cheshunt and neighbourhood : A. H. H. Several 

 places in Sussex and Kent : Mr. Jenner. 



On looking over Dillwyn's " Synopsis of British Confervte," 

 I was surprised to find under the head of Conferva spiralis 

 the following notice of the species just characterized : — 



" Since the Introduction was printed, a curious specimen 

 of this species has been gathered by Mr. Home of Clapham, 

 and examined by Mr. Woods, who gives the following ac- 

 count of it. ^ The plant is a pale dirty green, nearly with- 

 out gloss, about the size of C. sjnralis ; when magnified the 

 length of the joints is seen to be about equal to their width, 

 or a little more, and the sj^iral tube is in most parts nearly 

 obliterated ; but the chief singularity of this plant is in the 

 connecting processes, which are uniformly at the ends instead 

 of as usual in the middle of the joints, and each of which 

 appears to unite with the process of the next joint of the 

 same filament. No indication of the conjugation of two 

 filaments is to be observed ; the dark globules appear only 

 when the two joints are thus connected, and the adjacent 

 one is invariably empty.' " — Synopsis, p. 60. 



