268 BRITISH DESMIDIACE^. 



Cosmarium docidioides Liitk. (vol. i, p. 101). 



Docidium minutum Rail's, Brit. Desm. 1848, p. 158, t. 26, f. 5. 

 Penium minutuni W. & G. 8. West, Brit. Desm. vol. i, p. 101. 

 Dysphinctium minutum Liitkem. Gattung Penium, 1905, p. 337. 

 Cosmarium docidioides Liitkem. in litt. ; G. 8. West, Freshw. Alg. Columbia, 

 1914, p. 1037. 



Cosmarium Ralfsii Breb. (vol. ii, p. 141). 

 Var. rotundatum West. 



Cosmarium Ralfsii var. rotundatum West. Clare Island Alg. 1912, p. 19, 

 t. 2, f. 19. 



A variety with very rounded lateral margins to the 

 semicells, basal angles sometimes very slightly pro- 

 duced, sinus nearly closed. 



* */ 



Length 110^; breadth lOOjji ; breadth of isthmus 



24 LL. 



IRELAND.- -Near Westport, Mayo ! 



Cosmarium depressum (Nag.) Lund. (vol. ii, p. 176). 



Var. minor West. 



Cosmoriiini depressum var. minor West, Clare Island Algae, 1912, p. 19. 



Cells smaller than in the type. 

 Length 26 \L ; breadth 20 pi. 

 IRELAND. Clare Island. Mayo ! 



Cosmarium anceps Lund. (vol. iii, p. 47). 

 Var. tatricoides West. 



Cosmarium anceps var. tatricoides West, Clare Island Alga?, 1912, p. 1(3. 



Cells relatively broader than in the typical form, 

 isthmus compressed, but similar to that of C. tatricum 

 Racib. (that is, narrow, with conspicuously dilated 

 apex), cell- wall smooth. 



Length 33 \L ; breadth 21 JJL. 



IRELAND. Clare Isle, Mayo ! 



" ./ 



