lo Minnesota Algae 



West Indies. With the type from the above-named localities. On lime 

 trees. Shanford Estate. Dominica. (Elliott). 



i6. Chroococcus membraninus (Meneghini) Naegeli. Gatt. Einz. Alg. 46. 

 1849. De Toni. Syll. Algar. 5: 23. 1907. 



Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 25. no. 1201. 1905. 



Plant mass somewhat membranaceous, mucous, lead-colored to green, 

 becoming blackish; plants 3-8 mic. in diameter, globose or subglobose, sin- 

 gle, or associated in families of twos or fours; families 8-26 mic. in diameter; 

 sheaths thick, mucous, hyaline; cell walls thick, colorless; cell contents 

 minutely granular, blue or blue-green. 



California. Forming a zone, yellowish red just above, and blue-green 

 just below, the edge of the water, very low, in "The Lagoon," Niles, Ala- 

 meda County. November 1898. (Setchell). 



17. Chroococcus limneticus Lemmermann. Beitrage zur Kenntniss der 



Planktonalgen. Bot. Centralb. 76: 153. 1898. De Toni. Syll. Algar. 

 5: 16. 1907. 



Snow. The Plankton Algae of Lake Erie. U. S. Fish Commission Bull, 

 for 1902. 22: 392. 1903. 



Plate L fig. 8. 



Plant mass floating free; tegument wide; plants 8-13 mic. in diameter, 

 much crowded, before division globose, after division hemispherical; sheaths 

 hyaline, distinct, lamellose; cell contents greenish or pale blue-green. 



Ohio. Put-in-Bay. Lake Erie. Summers of 1898, 1899, 1900. (Snow). 



18. Chroococcus purpureus Snow. The Plankton Algae of Lake Erie. 



U. S. Fish Commission Bull, for 1902. 22: 388. 390. 1903. 



Plate I. fig. 9. 



Plant mass gelatinous, floating free; tegument wide; plants 13 mic. in 

 diameter, spherical, or just before division elongated, usually arranged two 

 by two in colonies of four or eight; sheaths thin; cell contents grayish-pur- 

 ple, changing to brown under unfavorable conditions. 



Ohio. Common in the plankton of Lake Erie. Put-in-Bay. (Snow). 



Genus SYNECHOCYSTIS Sauvageau. 

 Bull. Soc. Bot. de France. 39: cxv. 1892. 



Plants always globose; sheaths none; cell walls thin not diffluent; cell 

 contents blue-green; reproduction by division of the cells in one direction 

 only. 



J 9. Synechocystis aquatilis Sauvageau. Sur les Algues d'eau douce recol- 



tees en Algerie pendant la session de la Societe Botanique en 1892. 



Bull. Soc. Bot. de France. 39: cxvi. pi. 6. f. 2. 1892. De Toni. SylL 



Algar. 5; 26. 1907. 



Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 25. no. 1206. 1905. 



