Myxophyceae 265 



Indies. Guadeloupe. (Maze). Hawaii. On other algae. In tide pools at 



half tide. Waianae, Oahu. May 1900. (Tilden). 



Forma simulans Collins in Collins, Holden and Setchell. Phyc. Bor.-Am. 

 Fasc. 29. no. 1406. 1907. 



Filaments stout; color from light blue-green to purple or dull rose. 



Massachusetts. On Z o s t e r a. Mattapoisett. October 1906. Appearing 

 like C. confervicola (Roth) Ag., but with intercalary heterocysts. 

 (Collins). 



476. Calothrix epiphytica West and West. Welwitsch's African Freshwater 



Algae. Journ. of Bot. 35: 240. 1897. De Toni. Syll. Algar. 5: 621. 

 1907. 



West and West. Journ. Linn. Soc. Bot. 34: 285. 1898-1900. 



Filaments 5-7.5 mic. in diameter at the base, 250 mic. rarely up to 350 

 mic. in length, minute, attached to larger algae, solitary or somewhat gre- 

 garious, gradually tapering from base to apex; sheaths somewhat thick, 

 transparent and colorless; trichomes 3.5-4 mic. in diameter at the base, 

 ending in ^ very thin hair at the apex; cells equal to the diameter, in length, 

 or at the base a little shorter; heterocysts basal, solitary, small. 



West Indies. Epiphytic on Tolypothrix. Dominica. (Elliott). 



477. Calothrix scytonemicola n. sp. 



Plate XVII. fig. 7. 



Filaments 7-8 mic. in diameter, isolated or in small groups, the lower 

 portion attached to host, the remainder erect and free, ending in a hair 

 point; sheaths not distinct; heterocj'Sts 8 mic. in diameter, basal, usually 

 two in number, somewhat globose. 



Hawaii. Growing on filaments of Scytonema crispum. Very 

 abundant. In stagnant water in pool on beach, among roots of Water hya- 

 cinth. Meheiva, Makao, Koolauloa, Oahu. June 1900. (Tilden). 



478. Calothrix stagnalis Gomont. Note sur un Calothrix sporifere. (Calo- 



thrix stagnalissp. n.). Morot. Journ. de Bot. 9: 197. f. i, 

 2. 1895. De Toni. Syll. Algar. 5: 619. 1907. 

 Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 23. no. 1114. 1903. 

 Collins. Notes on Algae. — VII. Rhodora. 8: 123. 1906. 



Plate XVII. fig. 8, 9. 



Filaments 8-10 mic. in diameter in the middle portions, up to i mm. 

 in length, gregarious, radiating, decumbent and thickened at the base, erect, 

 sickle-shaped; sheaths thin, close, papery, transparent; trichomes 6-9 mic. 

 in diameter, especially constricted at joints, gradually tapering into a hair; 

 cells 6-10 mic. in diameter, unequal, usually subquadrate or longer than 

 the diameter; heterocysts in pairs, basal, yellowish, spherical or somewhat 

 quadrate; gonidia lo-li mic. in width (with sheath 12-14 mic wide), 26-40 

 mfc. in length, yellowish; wall of gonidium smooth. 



Massachusetts. In stellate tufts, rather sparsely distributed on various 

 filamentous algae, in swamp. Medford. August 1903. (Collins). 



479. Calothrix fusca (Kuetzing) Bornet and Flahault. Revis. des Nostoc. 



Ann. Sci. Nat. Bot. VII. 3: 364- 1886. De Toni. Syll. Algar. 5: 617. 

 1907. 



