Myxophyceae ^57 



Wolle. Fresh Water Algae. II. Bull. Torr. Bot. Club. 6: 138. 1877. (M. 

 terrestris Desmaz.); Fresh-Water Algae U. S. 305. pi. 203. f. 7-9; pi. 

 205. f. 16, 17. 1887. Collins. Algae of Middlesex County. 15. 1888. Ben- 

 nett. Plants of Rhode Island. 115. 188. Wolle and Martindale. Algae. 

 Britton's Catalogue of Plants found in New Jersey. Geol. Surv. N. J. 2: 

 609. 1889. Saunders. Protophyta-Phycophyta. Flora of Nebraska. 20. pi. 

 2. f. 21. 1894; The Algae. Harriman Alaska Expedition. Proc. Wash. Acad. 

 Sci. 3: 397. 1901. Collins. The Algae of Jamaica. Proc. Am. Acad. Arts 

 Sci. 37: 240. 1901. Setchell and Gardner. Algae of Northwestern America, 

 Univ. Calif. Pub. Bot. i: 189. 1903. Collins, Holden and Setchell. Phyc, 

 Bor.-Am. Fasc. 21. no. loii. 1903. Buchanan. Notes on the Algae of 

 Iowa. Proc. Iowa. Acad. Sci. 14: 12. 1908. 



Plate VI. fig. 29. 



Filaments creeping, rarely entangled and twisted, sometimes branched; 

 forming a black, glistening sheet; sheaths cylindrical, more or less un- 

 equal in outline, agglutinated, pointed and closed at the apex, or open and 

 gradually disappearing, at times entirely diffluent; trichomes 3.5-7 mic. in 

 diameter, not constricted at joints, many within the sheath, closely crowded, 

 usually twisted into cords, the portion extruding from the sheath straight; 

 apex of trichome gradually tapering and capitate; outer membrane of apical 

 cell thickened into a depressed conical calyptra; cells 3-7 mic. in length; 

 transverse walls frequently granulated. 



Alaska. Forming, with other algae, a thin coating on damp ground, 

 recently covered by snow. Glacier Bay. (Saunders). Massachusetts. 



Newton. (Farlow). Melrose. (Collins). Rhode Island. Common. (Ben- 

 nett). New Jersey. On moist earth. (Wolle). Iowa. Damp ground. 

 Grinnell. (Fink). On flower pots in greenhouse. Ames. (Buchanan). Ne- 

 braska. On damp earth in greenhouses. University. (Saunders). Wash- 

 ington. La Conner, Skagit County. (Gardner). California. In a gutter. 

 Berkeley. February 1902. (Gardner). West Indies. On moist rock. Rio 

 Cobre, Bog Walk, Jamaica. April 1893. (Humphrey). 



302. Microcoleus lacustris (Rabenhorst) Farlow in Farlow, Anderson and 

 Eaton. Algae. Am. Bor. Exsicc. no. 227. 1877. Gomont. M-onogr. 

 Oscill. 97. 1893. De Toni. Syll. Algar. 5: 376. 1907. 



Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 7. no. 307. 1897. 

 Setchell. Notes on Cyanophyceae. III. Erythea. 7: 52. 1899. Riddle. 

 Brush Lake Algae. Ohio Nat. 5: 268. 1905. 



Filaments simple or vaguely branched, forked at the apex, twisted 

 and entangled forming a black or blue-green layer; sheaths somewhat thin, 

 mucous and agglutinated, sometimes diffluent, often gradually disappear- 

 ing at the apex; trichomes 4-5 mic. in diameter, especially constricted at 

 joints, somewhat parallel, the portion extruding from the sheath very 

 straight; apical cell more or less obtuse conical, not capitate; cells 6-12 

 mic. in length; transverse walls not granulated; cell contents showing scat- 

 tered coarse granules, pale blue-green. 



Massachusetts. Newton. (Farlow). Connecticut. In tangled felty 



strata and disseminated among Scytonema crispum, in pool. North 



