Myxophyceae 245 



mic. in diameter, 3 decimill. long, decumbent, slender, densely interwoven, 

 irregularly and sparingly branched; branches erect, flexuous, somewhat toru- 

 lose, equal in diameter to the primary filament; sheaths thick, colorless 

 or yellowish; cells somewhat spherical, loosely arranged in a single row, 

 rarely in two rows; heterocysts scattered; cell contents pale blue-green. 



New Hampshire. One of the species composing the brown coating on 

 the wall of the "Flume." (Collins). Massachusetts. In gelatinous masses, 

 on dripping rocks. Cascade, Middlesex Fells. A^ril 1896. (Collins). West 

 Indies. On trees. Summit of Trois Pitons (4,500 feet) ; on rocks, Roseau 

 Valley (1,000-2,000 feet), June 1892; abundant on banks, Morne Micotrin; 

 on roadside and on bank near Roseau Lake (2,700 feet) ; on rocks, Castle 

 Bruce River (2,000-3,000 feet), Dominica, January, February 1896. (Elliott). 



Var. tenue West and West. 1. c. 30: 273. pi. 15. f. 4-8. 1895. De Toni. 

 1. c. 578. 



Plate XV. fig. 13. 



Filaments more slender, 5.5-7 mic. in diameter. 



West Indies. With the typical form but much more abundant. (Elliott). 



Var. rhizodes (Kuetzing) Hansgirg. Prodromus der Algenflora von 

 Bohmen. 2: 25. 1892. De Toni. 1. c. 578. 



Wolle. Fresh- Water Algae U. S. 274. 1887. 



Plant mass brownish black; filaments 8-12 mic. in diameter; branches 

 unilateral, slightly tapering or thickened at the apices. 



Vermont. On moist rocks. Charlotte. (Wolle). 



449. Stigonema aerugineum n. sp. 



Plate XV. fig. 14. 



Plant mass forming a brown, membranous layer; filaments 25 mic. in 

 diameter, rounded at apices, rare, mixed with other algae; branches short, 

 straight, spreading; sheaths thick, homogeneous, colorless; cells 14 mic. 

 in diameter, 6-8 mic. in length, oval or depressed globose, crowded, usually 

 forming a single row; heterocysts 8 mic. in diameter, somewhat spherical; 

 cell contents bright blue-green. 



Hawaii. Covering bottom of pool. On Puna Road, thirteen miles from 

 Hilo, Hawaii. July 1900. (Tilden). 



450. Stigonema panniforme (Agardh) Kirchner. Algen Kryptogamen- 



Flora von Schlesien. 230. 1878. Bornet and Flahault. Revis. des 

 Nostoc. Ann. Sci. Nat. Bot. VH. 5: 71. 1887. De Toni. Syll. Algar. 

 5: 580. 1907- 

 Wood. Contr. Hist. Fresh-Water Algae North America. 73. pi. g. f. 3. 

 1872. (Sirosiphon argillaceus Wood). Wolle. Fresh Water Al- 

 gae. III. Bull. Torr. Bot. Club. 6: 185. 1877; Fresh-Water Algae U. S. 273. 

 1)1. 193. f. 12, 13. 1887. Bennett. Plants of Rhode Island. 114. 1888. 



(Sirosiphon pulvinatus Breb.). Wolle and Martindale. Algae. 

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

 605. i88g. Hauck and Richter. Phykotheka Universalis. Fasc. 4. no. 645. 

 3889. West and West. On some Freshwater Algae from the West Indies. 



