vol.i] Setchell— Gardner. — Algce of Northwestern America. 20o 



tare of the frond. Only one of these resulting cells divides again, 

 the other remains in position and undivided. Prom this, it 

 happens that the cells are not all in a peripheral layer as Nsegeli 

 (1S49. p. 74. pi. Ill, A.) has described for his Oocardimn stratum, 

 but are scattered throughout the frond as shown in our figure. 

 The stalks of the cells, also, are different from those of the 

 species just referred to, in that they taper downwards. The 

 stalks take on a deep blue color immediately upon being treated 

 with Chloriodide of Zinc. 



On stones and pebbles in a shallow pool, middle litoral zone, 

 in a single locality much exposed to heavy seas, on the west 

 coast of Whidbey Island., Wash., N.L.G., No. 403!, and in 

 Collins, Holden and Setchell, P. B.-A., No. 909! A few speci- 

 mens of this species have also been collected at the Farallones, 

 near San Francisco. California, by R. A. Harper and W. J. V. 

 Osterhout. 



Family PLEUROCOCCACE.E. 



Schizochlamys gelatinosa A. Braun. 



Forming; light green, lobulated masses at the bottom of a 

 small pond of fresh water. Amaknak Island, Alaska, W.A.8. 

 andA.A.L., No. 5046a! 



Oocystis solitaria f. major Wille. 



On rocks, dripping with fresh water. Near Iliuliuk, Unalaska, 

 Alaska. W.A.S. and A.A.L., No. 4028! 



The plant referred to this form of the species measures some- 

 what less than the dimensions given, but is decidedly larger than 

 the typical form. 



Oocystis solitaria f. crassa (Wittrock) Hansgirg. 



Forming a mucous coating on damp rocks near waterfalls. 

 •Juneau, Alaska, Saunders, No. 75! (1901, p. 409). 



Selenastrum Bibraianum Reinsch. 



Among weeds in ponds of fresh water. Near Seattle, Wash., 

 Professor T. G. D. Kincaid, No. 768! 



There is an abundance of material of this species in the 

 specimen quoted. 



