200 Minnesota Algae 



Plate X. fig. s- 



Plant mass rust-colored, gelatinous; trichomas 2.8 mic. in diameter, gen- 

 erally curved and entangled, sometimes straight, more or less constricted 

 at the joints; cells cylindrical; heterocysts hirsute, spherical; gonidia 6-6.5 

 mic. in diameter, 16-19 niic. in length, elliptical, very minutely granulate; 

 cell contents homogeneous or granular, light blue-green. 



New Jersey. Forming, with other algae, a ferruginous brown, gelatinous 

 mass, growing in a deep, shaded, very stagnant pool. Spring Garden. 

 (Wood). In wet places on dead wood. (Wolle). Minnesota. Irving 



Chase Lake. July 1893. (Tilden). Nebraska. Lincoln. (Bessey). Forms 

 light green, slimy strata on pots in greenhouse. Lincoln. (Saunders). 



368. Cylindrospermum minutissimum Collins. New Cyanophyceae. Erythea. 



4: 120. 1896; Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 

 26. no. 1256. 1905. De Toni. Syll. Algar. 5: 472. 1907. 

 Plant mass loose, blue-green; trichomes 2-2.5 mic. in diameter, straight, 

 not constricted at joints; cells cylindrical, very slender, 4-5 mic. in length; 

 heterocysts 4 mic. in diameter, 7-8 mic. in length, cylindrical-oblong; go- 

 nidia 8-9 mic. in diameter, 18-20 mic. in length; wall of gonidium smooth, 

 translucent (in not quite ripe gonidia). 



Massachusetts. Among other algae 'in a scum in a ditch. Maiden. Octo- 

 ber 1890. (Collins). 



369. Cylindrospermum muscicola Kuetzing. Phyc. Germ. 173. 1845. Bornet 



and Flahault. Revis. des Nostoc. Ann. Sci. Nat. Bot. VII. 7: 254. 



1888. De Toni. Syll. Algar. 5: 477. 1907. 

 Collins. Algae of Middlesex County. 14. 1888. Tilden. American Algae. 

 Cent. II. no. 174. 1896. Collins. The Algae of Jamaica. Proc. Am. Acad. Arts 

 Sci. ZT. 240. 1901. Setchell and Gardner. Algae of Northwestern Amer- 

 ica. Univ. Calif. Pub. Bot. i: 193. 1903. Collins, Holden and Setchell. 

 Phyc. Bor.-Am. Fasc. 27. no. 1306. 1906. 



Plate X. fig. 6. 



Plant mass expanded, mucous, blackish green; trichomes 3-4.7 mic. in 

 diameter, cylindrical, slightly constricted at joints; cells 4 mic. in length; 

 heterocysts 4 mic. in diameter, 5-7 mic. in length, oblong; gonidia 9-12 

 mic. in diameter, 10-20 mic. in length, oval, orange brown; wall of go- 

 nidium smooth; cell contents pale blue-green. 



Maine. On steep, wet clay bank. Harpswell. July 1906. (Collins). 

 Massachusetts. Cambridge. (Farlow). On moist ground, Medford. Septem- 

 ber 1906. (Lambert). Washington. In a small stream of running water. 

 Orcas Island. (Gardner). California. In slowly running water. Pasadena. 

 December 1895; (McClatchie). West Indies. On sides of basin. Constant 

 Spring; on sand at edge of river, Castleton, April 1893. (Humphrey). 



370. Cylindrospermum licheniforme. (Bory) Kuetzing. Diagnosen und Be- 



merkungen. Bot. Zeit. 5: 197. 1847. Bornet and Flahault. Revis. des 

 Nostoc. Ann. Sci. Nat. Bot. VII. 7: 253. 1888. De Toni. Syll. 

 Algar. s: 476. 1907. 



