i68 Minnesota Algae 



mic. in length, oval or elliptical, separated when mature, with a smooth, 

 transparent thin outer membrane. 



Alaska. Forming brown, floating masses of jelly on surface of streams. 

 Glacier Valley, Unalaska. (Lawson). Connecticut. Floating in a spring, 

 in irregularly rounded masses, from the size of a pin head to S cm. in 

 diameter. Mount Carmel. October 1907. (Graves). Washington. Green 

 Lake, Seattle. (Gardner). 



318. Nostoc spongiaeforme Agardh. Syst. Algar. 22. 1824. Bornet and 

 Flahault. Revis. des Nostoc. Ann. Sci. Nat. Bot. VII. 7: 197. 1888. 

 De Toni. Syll. Algar. 5: 397. 1907. 

 Tilden. American Algae. Cent. I. no. 83. 1894; List of Fresh-water Algae 

 collected in Minnesota during 1894. Minn. Bot. Stud, i: 236. 1895. Rich-^ 

 ter. Siisswasseralgen aus dem Umanakdistrikt. Bib. Bot. 8: Heft. 42. A. 5. 

 1897. Tilden. Am. Alg. Century VI. no. 579. 1902. Collins, Holden 

 and Setchell. Phyc. Bor.-Am. Fasc. 22. no. 1064. 1903. Setchell and 



Gardner. Algae of Northwestern America. Univ. Calif. Pub. Bot. i: 190. 

 1903. Lemmermann. Algenfl. Sandwich-Inseln. Bot. Jahrb. 34: 622. 190^. 

 Tilden. American Algae. Cent. VII. Fasc. I. no. 633. 1909. 



Plate VII. fig. 4, 5. 



Colonies gelatinous, at first globose, afterwards expanded, verrucose, 

 bullose, pale blue-green-violet, or reddish; filaments flexuous, loosely en- 

 tangled; sheaths in the interior confluent, those near the outside of the 

 mass more or less distinct, yellowish or dark-colored; trichomes about 4 

 mic. in diameter, blue-green or violet; cells different in shape, some cylin- 

 drical, up to 7 mic. in length, others barrel-shaped or depresed-spherical; 

 heterocysts 7-8 mic. in diameter, somewhat globose or oblong; gonidia 6-7 

 mic. wide, 10-12 mic. long, oblong, separated; wall of gonidium smooth, 

 later becoming dark-colored. 



Greenland. Ikerasak. Very abundant. (Richter). Minnesota. Floating 

 on surface of water in tank. State Fish Hatcheries, St. Paul. September 

 1894; on mosses and weeds in stagnant pond and on muddy ground. Wood- 

 land Park, Duluth. (Tilden). Washington. Floating in a small pool of 

 fresh water. Edge of Green Lake, Seattle. (Gardner). California. Lake 

 Chabot, San Leandro, Alameda county. June 1902. (Osterhout and Gard- 

 ner). Hawaii. In bogs in Nuanu, Oahu. (Schauinsland). 



319 A. Nostoc ellipsosporum (Desmazieres) Rabenhorst. Fl. Eur. Algar. 2: 

 169. 1865. Bornet and Flahault. Revis. des Nostoc. Ann. Sci. Nat. 

 Bot. VII. 7: 198. 1888. De Toni. Syll. Algar. 5: 398. 1907. 

 Schramm and Maz6. Essai Class. Algues Guadeloupe. 29. 1865. 



(Hormosiphon antillarum S. and M.). Maze and Schramm. 



Essai Class. Algues Guadeloupe. 14. 1870-1877. (L. antillarum Crouan). 



Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 2. no. 59. 1895. 



Plate VII. fig. 6-10. 



Plant mass gelatinous, expanded, adhering by under surface, irregular- 

 ly mammillary, reddish or dark-colored; filaments flexuous, laxly en- 

 tangled; trichomes 4 mic. in diameter, pale blue-green or olive; cells 



