82 Minnesota Algae 



Plate IV, fig. 35- 



Plant mass dark blue-green; trichomes 5.5-9 mic. in diameter, straight 

 (in dried material fragile), evidently constricted at joints, gradually taper- 

 ing for some distance from apex; apex of trichome undulating, hooked or 

 curved at extremity; apical cell obtuse or somewhat pointed, not capitate; 

 calyptra none; cells 2.7-4.5 i^ic. in length; apical cell somewhat quadrate 

 or up to 8 mic. in length; cell contents finely granular. 



Washington. In pond of brackish water. Monroe's Landing, near 

 Coupeville, Whidbey Island. (Gardner). 



164. Oscillatoria chalybea Mertens in Jiirgens. Algae aquat. Decas 13. no. 



4. 1822. Gomont. Monogr. Oscill. 252. 1893. De Toni. Syll. Algar. 



5: 185. 1907. 



Wolle. Fresh-Water Algae U. S. 314. pi. 206. f. 17-21. 1887. Tilden. 



A new Oscillatoria from California. Bull. Torr. Bot. Club. 23: 58. i8g6. 



(O. trapezoidea Tilden). Setchell. Oscillatoria trapezoidea Tilden. 



Erythea. 4: 69. 1896. Bessey, Pound and Clements. Additions to the 



Reported Flora of the State. Bot. Surv. Nebraska. 5: 13. 1901. Snow. The 



Plankton Algae of Lake Erie. U. S. Fish Comm. Bull, for 1902. 22: 392. 1903. 



Collins, Holden and Setchell. Phyc. Bor.-Am. Ease. 21. no. looi. 1903. (O. 



chalybea genuina). Collins. Phycological Notes of the late Isaac 



Holden. — I. Rhodora. 7: 172. 1905. 



Plate IV. fig. 36. 



Plant mass dark green; trichomes 8-13 mic. in diameter, fragile, 

 straight, or sometimes twisted in loose spirals, slightly constricted at joints, 

 gradually tapering for a long distance from the apex; apex hooked or 

 curved; apical cell obtuse, not capitate; calyptra none; cells 3.6-8 mic. long; 

 transverse walls not at all or scarcely granulated; cell contents finely 

 granular with scattered large refringent granules, dark blue-green. 



North America. (Pike, Martindale, Farlow). Connecticut. Outlet of 

 Fresh Pond; on woodwork, rocks and Eflteromorpha, below Yellow 

 Mill Bridge. May, June, November. (Holden). Florida. On wet ground, 

 (Wolle). Ohio. Plankton. Put-in-Bay, Lake Erie. (Snow). Nebraska. 

 In stagnant water. Waverly. (Bessey). California. Bottom of pond. Pasa- 

 dena. October^ 1895. (McClatchie). Lake (Jhabot, San Leandro. June 1902. 

 (Osterhout and Gardner). 



165. Oscillatoria subsalsa Agardh. Syst. Algar. 66. 1824. De Toni. Syll. 

 Algar. 187. 1907. 



Kjellman. Algae of the Arctic Sea. 323. 1883. 



Plant mass dark blue-green, mucous, radiating; trichomes 8-10 mic. in 

 diameter, straight, somewhat constricted at joints; apex of trichome equal 

 or slightly tapering, obtuse, straight or curved; cells 4-5 mic. in length; 

 cell contents granular, pale blue-green. 



Greenland. "According to a label it grows 'in fossis submarinis.' Baffin 

 Bay: Tessarmiut on the west coast of Greenland according to specimens 

 in the herbarium of the Copenhagen Museum." — Kjellman. 



