246 Minnesota Algae 



Journ. Linn. Soc. Bot. 30: 273. 1895. Collins, Holden and Setchell. 



Phyc. Bor.-Am. Fasc. 2. no. 61. 1893. Collins. Algae. Flora of the Blue 

 Hills, Middlesex Fells, Stony Brook and Beaver Brook Reservations of 

 the Metropolitan Park Commission, Massachusetts. 128. 1896; Phycolog- 

 ical Notes of the late Isaac Holden. — II. Rhodora. 7: 237. 1905. 



Plant mass caespitose, expanded, olive-black; filaments 24-36 mic. in • 

 diameter, up to I mm. in length, decumbent, flexuous, intricate, tapering 

 at the apices, irregularly branched; branches erect, agglutinated laterally 

 in fascicles, as thick as the primary filament; sheaths thick, yellowish or 

 yellowish-brown, roughened on the surface; cells short, separated, usually 

 in one series; heterocysts scattered; hormogones terminal, 20 mic. in diame- 

 ter, about 100 mic. in length. 



Maine. Growing on rocks and moss just above high water mark, but 

 wet by spray in rough weather. Cape Rosier. July 1894. (Collins). New 

 Hampshire. In crevices of rocks. Shelburne. August 1894. (Farlow). 

 Massachusetts. Wet rock. Middlesex Fells. (Collins). Rhode Island. 

 Pocasset Brook. (Bennett). Connecticut. On vertical faces of trap rocks. 

 Sargent's River, Woodbridge. November 1891. (Setchell). On moist rocks. 

 Sage's Ravine, below first falls, Salisbury. October. (Holden). New Jer- 

 sey. Frequent, on moist rocks. (Wolle). Pennsylvania. Wet mountain 

 cliff. Pike County. (Wolle). South Carolina. On a moist clay bank near 

 Aiken. August 1869. (Ravenel). West Indies. On trees. Summit of Trois 

 Pitons (4,500 feet); on rocks, Roseau Valley (1,000-2,000 feet), Dominica. 

 (Elliott). 



451. Stigonema tomentosum (Kuetzing) Hieronymus. Bemerkungen 



ueber einige Arten der Gattung Stigonema Ag. Hedwigia. 34: 166. 

 189S. De Toni. Syll. Algar. 5: 581. 1907. 



Wolle. Fresh- Water Algae U. S. 269. pi. 191. f. 1-20; pi. 19S. f. 16. 1887. 

 (Sirosiphon pulvinatus alpinus (Kg.) Wolle). 



Plant mass compact, woolly, up to 2 mm. in height, often cracked, crus- 

 taceous, brownish black; filaments 14-38 mic. in diameter; primary filaments 

 decumbent, giving off numerous elongate, erect, flexuous branches; branches 

 often densely agglutinated into fascicles; sheaths yellowish or brownish; 

 trichomes for the most part consisting of a single row of cells rarely of 

 two rows; cells of the older filamefits somewhat quadrate or spherical, 

 rarely somewhat cylindrical, each surrounded by a special, deeper colored 

 envelope; cells of the younger filaments 10-12 mic. in diameter, often com- 

 pressed, wider than long, with blue-green contents; heterocysts not rare, 

 lateral or oftener intercalary, somewhat quadrate or spherical, oftener com- 

 pressed, wider than long, yellowish; hormogones lo mic. in diameter, 40-100 

 mic. in length. 



West Virginia. Wet rocks. Black Water Creek. (Wolle). 



452. Stigonema ocellatum (Dillwyn) Thuret. Essai Class. Nostochinees, 



380. 1875. Bornet and Flahault. Revis. des Nostoc. Ann. Sci. Nat. 

 Bot. VII. s: 69. 1887. De Toni. Syll. Algar. 5: 578. 1907. 

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

 (Sirosiphon pluviale Crouan). Wood. Contr. Hist. Fresh-Water 



