14^ Minnesota Algae 



ill diameter, tenacious, curved, very densely entangled; sheaths moderately 

 wide, colorless, pellucid; trichomes 3.5 mic. in diameter, here and there 

 interrupted, often constricted at joints; cells 3.5-7 mic. in length; cell 

 contents pale blue-green. 



South Carolina. Sluggish water. Aiken. (Ravenel). 



274. Hypheothrix coriacea Kuetzing. Spec. Algar. 267. 1849. Gomont. Mon- 



ogr. Oscill. 47. pi. 8. f. 6, 7. 1893. (Schizothrix coriacea 



Gom.). De Toni. Syll. Algar. 5: 336. 1907. 

 Dickie. On the Algae found during the Arctic Expedition. Journ. Linn. 

 Soc. Bot. 17: 8. 1880. Collins, Holden and Setchell. Phyc. Bor.-Am. 

 Fasc. 14. no. 654. 1900. (Sch. coriacea (Kg.) Gom.). Collins. The 

 Algae of Jamaica. Proc. Am. Acad. Arts Sci. yj: 240. 1901. Collins, 

 Holden and Setchell. Phyc. Bor.-Am. Fasc. 18. no. 855. 1901. Collins. 

 Phycological Notes of the late Isaac Holden. — 11. Rhodora. 7: 236. 1905. 



Plate VI. fig. 2. 



Plant mass up to l.S cm. in thickness; widely expanded, encrusted with 

 calcium carbonate, crustaceous, leathery, roughened on the surface, green 

 becoming reddish, rose- or brick-colored on the outside, faded within; 

 filaments very densely entangled, scarcely to be separated without rup- 

 turing, very long and soft, usually moderately branched; sheaths cylindri- 

 cal, firm, somewhat close, slightly roughened, not lamellose, with very 

 gradually tapering apices; trichomes 1-1.7 mic. in diameter, few within 

 the sheath, somewhat parallel or solitary, constricted at joints; apical cell 

 acute-conical; cells 3-6 mic. in length; transverse walls indistinct; rarely 

 granulated; cell contents pale blue-green. 



Arctic Regions. Walrus Island, 79° 15' N. (Dickie). Connecticut. 

 Forming a felty stratum of yellowish or orange tint, on moist limestone 

 rocks, shore of Housatonic River, near Gaylordsville. October 1898 

 and April 1899. (Holden). California. Mixed with other algae, form- 

 ing a thin layer on the side of a watering trough. Dillon's Beach, En- 

 trance to Tomales Bay, Marin County. December 1898. (Setchell and 

 Gibbs). West Indies. In tufts on sides of lily tanks. Botanic Garden, 

 Castleton, Jamaica. April 1893. (Humphrey). 



Forma meneghinii Kuetzing. 1. c. 268. De Toni. 1. c. 337. 



WoUe. Fresh Water Algae. III. Bull. Torr. Bot. Club. 6: 182. 1877. 



Plant mass usually somewhat thick, pale red or flesh-colored; sheaths 

 2.8-4 mic. in thickness, up to four times thicker than the filaments. 



New Jersey. Damp earth. (Austin). 



275. Hypheothrix lardacea (Cesati) Hansgirg in Dalla Torre und Sarnth. 



Alg. v. Tyr. Vorarl. u. Liechtenst. 96. Gomont. Monogr. Oscill. 



49. pi. 8. f. 8, 9. 1893. (Schizothrix lardacea Gom.). De 



Toni. Syll. Algar. 5: 340. 1907. 

 Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 3. no. 105. 1895. 

 (S. lardacea (Ces.) Gom.). Setchell. Notes on some Cyanophyceae 

 of New England. Bull. Torr. Bot. Club. 22: 429. 1895. Tilden. American 



