48 Minnesota Algae 



cells 4-6 mic. in diameter, sptierical, usually solitary; cell contents homo- 

 geneous, pale green. 



Wyoming. On bottom of spring. Temperature 38° C. Frying Pan 

 Basin, July 1896; on rocks, near vent of geyser, sometimes heated, Nor- 

 ris Geyser Basin. June 1896; with Microspora amoenathermalis, 

 lying in overflow from spring. Temperature 41° C. Frying Fan Basin. July 

 1896. Yellowstone National Park. (Tilden). Forming a green coating on 

 floor of overflow channel. Temperature 49° C. Corfstant Geyser. Norris 

 Geyser Basin; in acid waters. Green Spring, between Norris Geyser Basin 

 and Beaver Lake. 1897. Yellowstone National Park. (Weed). California. 

 Forming an emerald green, rather thick coating on steaming rocks above 

 the "Devil's Kitchen," Geysers. Sonoma County. June 1900. (Setchell and 

 Hunt). 



"Clearly a member of the Cyanophyceae and forming a limited number 

 (4) of schizospores (gonidia) which seem to relate it most closely to the 

 genus Pleurocapsa." — Setchell. 



109. Pleurocapsa fuliginosa Hauck. Die Meeresalgen Deutschlands und 



Oesterreichs. 515. f. 231. 1885. De Toni. Syll. Algar. 5: 122. 1907. 

 Collins. Notes on New England Marine Algae. V. Bull. Torr. Bot. 

 Club. 18: 335. 1891. Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 

 3. no. loi. 1895. Setchell. Notes on Cyanophyceae. III. Erythaea. 7: 

 54. 1899. Collins, Holden, Setchell. Phyc. Bor.-Am. Fasc. 15. no. 704. 



1900. Collins. Preliminary Lists of New England Plants. — V. Marine 

 Algae. Rhodora. 2: 42.' 1900; Phycological Notes of the late Isaac Holden, — 

 I. Rhodora. 7: 172. 1905. 



Plate III. fig. 2, 3. 



Colonies thin, crustaceous, blackish; families 50-100 mic. in diameter; 

 sheaths colorless; cells 5-20 mic. in diameter, solitary or united in families 

 of twos, fours or eights; cell contents homogeneous, golden yellow, fawn- 

 colored or dull violet. 



Massachusetts. Forming a very thin reddish or brownish-black coating 

 on rocks- near high water mark. Marblehead. (Collins). Rhode Island. 



(Collins). Connecticut. On Enteromorpha and stones between 

 tides. Below Yellow Mill Bridge. May, August, November, December. 

 (Holden). In dark patches on stones and woodwork, also epiphytic on 

 Enteromorpha, mostly near high water mark. Bridgeport. December 

 1893. (Holden). California. Forming a smooth black covering on smooth 

 rocks, at high water mark in exposed places. Carmel Bay, Monterey Coun- 

 ty. January 1899. (Setchell and Gibbs). On piles of wharf at the Life 

 Saving Station at the Presidio; on old timbers. Alameda. (Setchell). 



Collins states that when the cells cease to divide, the contents change 

 into small round gonidia ("Spores"). 



110. Pleurocapsa amethystea Kolderup-Rosenvinge. Groenlands Haval- 



ger. Medd. om Groenland. 3: 967. fig. 57. 1893; Les Algues 

 Marines du Groenland. Ann. Sci. Nat. Bot. VII. 19:. 163. fig. 

 57. 1894. De Toni. Syll. Algar. 5. 121. 1907. 



