Myxophyceae 8l 



tra none; cells 2.5-5 mic long; transverse walls sometimes finely granulated; 

 cell contents bright blue-green. 



Canada. In tufts floating in water or on muddy bottom; in great abun- 

 dance in the impure water just below mouth of city sewer. Kettle Creek, St. 

 Thomas, Ontario. November 1896. (Lees). Connecticut. Floating in 

 stagnant marsh pool near "Fresh Pond" (brackish). Stratford. May 1900. 

 (Holden). Minnesota. University plant house, Minneapolis. January 

 1897. (Tilden). Nebraska. In culture in greenhouse. Lincoln. (Bessey). 

 California. Mountain lake, San Francisco. June 1902. (Osterhout and Gard- 

 ner). West Indies. Guadeloupe. (Maze and Schramm). In still water. 

 Roaring River, near St. Ann's Bay. March 1893; Castleton. April 1893. (Hum- 

 phrey). Hawaii. On sides of cliff at falls. Waialuka River, Hilo, Island 

 of Hawaii. July 1900. (Tilden). 



161. Oscillatoria numidica Gomont. Monogr. Oscill. 251. 1893. De Toni. 



Syll. Algar. 5: 183. 1907. 



Tilden. American Algae. Cent. I. no. 78. 1894; List of fresh-water Algae 

 collected in Minnesota during 1894. Minn. Bot. Studies, i: 236. 1895; Ameri- 

 can Algae: Cent. VI. no. 598. 1902. 



Plant mass dark blue-green; trichomes 2.5-4 "^ic. in diameter, straight, 

 fragile, constricted at joints, gradually tapering for some distance from the 

 apex; apex of trichome curved or undulating; apical cell obtuse, not capi- 

 tate; calyptra none; cells 2-8 mic. long; transverse walls not granulated; cell 

 contents uniformly granular; pale blue-green. 



Minnesota. In tanks clinging to water plants. Greenhouse. Minneapolis. 

 November 1894. (Tilden). On floating leaves and grasses in pool in stone 

 quarry. Minneapolis. October 1901. (Hone). 



162. Oscillatoria cortiana Meneghini. Conspectus Algol, eugan. 8. 1837. 



Gomont. Monogr. Oscill. 251. 1893. De Toni. Syll. Algar. 5: 183. 

 1907. 

 WoUe. Fresh Water Algae. III. Bull. Torr. Bot. Club. 6: 183. 1877; 

 Fresh-Water Algae U. S. 313. pi. 206. f. 15. 1887. 



Plate IV. fig. 34- 



Plant mass dull or dark blue-green; trichomes 5.5-8 mic. in diameter, 

 especially straight, fragile, slightly constricted at the joints, gradually ta^ 

 pering for some distance from the apex, curved or undulating at the ex- 

 tremity; apical cell obtuse, not capitate; calyptra none; cells 5-4-8.2 mic. 

 in length (apical cell up to 14 mic. long); transverse walls not granulated; 

 cell contents showing scattered protoplasmic granules, blue-green. 



Pennsylvania. Floating on hot waste water at a large steam mill. Near 

 Bethlehem. (Wolle.) 



163. Oscillatoria okeni Agardh. Aufzahlung, etc. Flora. 10: 633. 1827. Go- 



mont. Monogr. Oscill. 252. pi. 7. f. 18. 1893. De Toni. Syll. Algar. 

 5: 185. 1907. 

 Setchell and Gardner. Algae of Northwestern America. Univ. Calif. 

 Pub. Bot. i: 184. 1903. 



