COSMABIUM. 101 



Madagascar. Central and E. Africa. Azores. United 

 States. AY. Indies. Ecuador. Uruguay. Argentina. 

 Patagonia. 



C. /cere is a species with a wide distribution and a varied 

 habitat. It does not frequent Sphagnum-areas, but thrives 

 in small pools,, ponds, ditches, and on dripping rocks. It may 

 sometimes be obtained in great abundance with scarcely any 

 intermixture of other Algse. We have examined two such 

 pure collections, one from the north of France and one from 

 Hanka Deela, Somaliland. The form of the semicells is 

 somewhat variable, especially with regard to the roundness 

 of the basal angles and their ereneral inflation. The slight 



o * ' 



retuseness in the middle of the apex is characteristic of all 

 forms of the species. 



The zygospores occurred abundantly on rocks in a river- 

 bed in Koh Chang in the Grulf of Siam (consult W. & Gr. S. 

 West, 'Freshw. Chlor. Koh Chang/ 1901, p. 87, t. 2, f. 14). 

 We had previously attributed a spiny zygospore to this 

 species, but we now know this to be an error (consult A\ . & 

 G. S. West, 'New and Int. Freshw. Alg. ; 1896, p. 154, t. 4, 

 f. 35 ; and West, ' Alg. aq. dnlc. Lusitan.' 1892, p. 1502). 



Borge has described a " forma major ' ' from South Pata- 

 gonia, but in size this form scarcely exceeds the dimensions 

 of some of the common and widely distributed forms (consult 

 Borge, ' Siisswasseralo-eii Siid-Patagoii/ 1901, p. 24, t. 1, 

 f. 7; length 32-36 ^ ; breadth 23-26 /u). 



The smallest known forms have been described from Central 

 and West-central Africa (C. l%ve var. minimum West & G. S. 

 West, <Welw. Afric. Freshw. Algae/ 1897, p. 119, t. 368, f. 6). 



Var. octangularis (AYille) nob. (PL LXXIII, fig. 20.) 



Cosmarium Meneghinii Breb. forma octangularis Wille, Ferskv. Alg. Nov. 

 Semlj 1S79, p. 43, t. 12, f. 35: Boldt, Desniid. Gronland, 1888, p. 13; 

 West. Alg. W. Ireland, 1S92, p. 148: Alg. Engl. Lake Distr. 

 p 726 West & G. S. West, Alg. S. England, 1897, p. 487 ; G. S. West, 

 Alga-fl. Cambr. 1899, p. 216 ; West & G. S. West, Alga-fl. Yorks. 

 p. 93 ; Alg. N. Ireland, 1902, p. 35 ; Freshw. Alg. Orkneys and Shetlands, 



1905 p. 22. 



C. Ixve Eabenh. var. undulata Sclimidle, Alg. Geb. Oberrlieins, 1893, 

 p. 548, t. 28, f. 5 ; Beitr. alp. Algenfl. 1896, p. 387 ; Lappmark Siiss- 

 Avasseralgen, 1898, p. 27. 



Semicells angular, irregularly 8-sided including the 

 broad base ; each lateral margin consisting of three 

 short, straight, or very slightly concave sides ; apex 

 ret use as in the type. 



