Myxophyceae 217 



burne. (Farlow). Massachusetts. Newton. (Farlow). On shaded rocks. 

 High Ledge, Melrose. April 1892. (Collins). Connecticut. On old stumps. 

 Shore of upper Twin Lake, Salisbury. October. (Holden). New Jersey. 

 On moist earth, wood and rocks. (WoUe). Nebraska. On damp wood, 

 in greenhouses. State University, Lincoln. (Bessey, Saunders). California. 

 On rocks. North side of Bolinas Ridge, Marin County. June 1896. (Setch- 

 ell). West Indies. Forming violet-colored masses among mosses on lime- 

 stone rocks in mountains near Utuado, Porto Rico. (Moebius). On steps 

 of Court House, Port Antonio. April 1893; on leaves of trees, Bath, Jamaica. 

 (Humphrey). Head of Castle Bruce River, Dominica. January and February 

 1896. (Elliott). 



Forma brunnea Wolle. Fresh-Water Algae U. S. 258. 1887; Fresh 

 Water Algae. Bull. Torr. Bot. Club. 6: 284. 1879. (S. cortex bruneum 

 Wolle). De Toni. 1. c. Si5- 



Plant mass dark brown; filaments covered with apparently "sub-spheri- 

 cal, resinous cells." 



South Carolina. (Ravenel). Florida. (Ravenel, Smith, Austin). 



Var. symplocoides (Reinsch) Bornet and Flahault. 1. c. 99. De Toni. 

 I. c. 515. 



Maze and Schramm. Essai Class. Algues Guadeloupe. 36. 1870-1877. 

 (Calothrix conferta Crouan). 



Sheaths colorless; cell contents pale blue-green. 



West Indies. (Maze). 



Var. calcicolum Hansgirg. Physiologische und Algologische Mittheil- 

 ungen. pi. 3. f. 35. 1890; Prodromus der Algenflora von Bohmen. 2: 33. 1892. 

 De Toni. 1. i;. 516. 



Plant mass smooth, brown or black, rarely almost soft, gelatinous, often 

 expanded; filaments 6-12 mic. in diameter, more or less branched, curved, 

 often associated in dense floccose masses; false branches somewhat more 

 slender, single or in pairs, approximate, usually issuing between two hetero- 

 cysts, erect; sheaths close, somewhat thickened with age, yellow or yellow- 

 ish orange, rarely almost colorless; trichomes 4-6 mic. in diameter; cells 

 almost inconspicuous, somewhat quadrate or twice as short as wide, hetero- 

 cysts somewhat quadrate, single or in pairs, a little shorter or longer than 

 their diameter; cell contents granular, dull blue-green, green, olive or yel- 

 lowish. 



South Carolina. (Ravenel). Florida. (Smith, Austin, Ravenel). 



399. Scytonema varium Kuetzing. Spec. Algar. 307. 1849. Bornet and Fla- 

 hault. Revis. des Nostoc. Ann. Sci. Nat. Bot. VII. 5: 97. 1887. De 

 Toni. Syll. Algar. 5: 512. 1907. 



Maze and Schramm. Essai Class. Algues Guadeloupe. 34. 1870-1877. 

 Wolle. Fresh Water Algae. II. Bull. Torr. Bot. Club. 6: 139. 1877. (S. 

 chrysochlorum Kg.) ; Fresh-Water Algae U. S. 253. 1887. Saun- 

 ders. The Algae. Harriman Alaska Expedition. Proc. Wash. Acad. Sci. 3: 

 398. 1901. Setchell and Gardner. Algae of Northwestern America. Univ. 



