108 BIOLOGY OF THE RICHMOND RIVER, 



Var. RiCHMONDi^, n.var. (PL ii., f.l2). 



Chloroplasts bright translucent green, 2-4 large pyrenoids, 

 generally 4 at the angles of a tetraedron. 



Coenob. (16 cell) diam. 130, cell. 16-18 /x. 



Lismore (12). 



As Wallich remarks (in Turner, I.e.) about the preceding form, 

 the cells (from a certain point of view at any rate) are so arranged 

 in alternating superimposed squares, that the whole sixteen can 

 be seen at one time. Pandorina morum present also. 



UvA, n.gen. 



Character idem ac speciei. 



UvA Casinoknsis, sp.unica. (PI. ii., f.l3). 



Coenobium uviforme, ovatum, fronte latius, e cellulis muco 

 agglutinatis non autem in volutin, exstructum; cellulis circa 16 

 (18,16,32) magnis, ovatis, declinatis; flagellis longis (? binis); 

 chloroplastidibus clare viridibus, granulosis, pyrenoidibus nuUis 

 (visis); stigmatibus obscuris. 



Coenob. long. 28-40, lat. 22-.. ; cell. long. 10-14, lat. 6-10 />t. 



Casino (14). Plentiful. 



This interesting flagellate was obtained from the river at 

 Casino, out of Hydrodictyon reticidatura. The cells in the 

 smaller specimens are distinctly ovate, with the narrower ends 

 pointing backwards ; but, with growth, they tend to become 

 more nearly elliptical. I was not able to see whether theflagella 

 are double or single; they are very long, quite equal to the 

 breadth of the coenobium, and seem to arise, not as one would 

 suppose, from the point, but from the broad end of the cell. The 

 organism moves straight forward, broad end first, with the 

 oreatest rapidity, revolving at the same time round its long axis, 

 very different from the leisurely progression of Eudorina and 

 Pandorina. 



For genus Trochisia, see under Chytridiacece, infra. 

 Genus Hydrodictyon Roth. 

 Hydrodictyon reticulatum (L.) Lag. 



Cellulse perfecte cylindracese, endochroma in reticulo irregulari 

 disposita, pyrenoidibus minutis dispersis. 



Cell. long. 200-300, lat. 36-44 /x. 



