Myxophyceae 137 



trichomes 14-21 mic. in diameter, not constricted at joints; apex of trich- 

 oma tapering, truncate; cells 2.5-3.5 mic. in length; transverse walls gran- 

 ulated. 



Massachusetts. (Collins). Connecticut. Forming a Phormidium- 

 like coating on iron pillars between tide marks. Black Rock Beacon, 

 near Bridgeport. July 1892. (Holden). New York. Peconic Bay, Long 

 Island. (Farlow). West Indies. Guadeloupe. (Maze). Barbados. (Vick- 

 ers). 



262. Hydrocoleus holdenii Tilden. Rhodora. 3: 254. 1901. De Toni. Syll. 



Algar. s: 319. 1907. 



Holden. Two new species of Marine Algae from Bridgeport, Con- 

 necticut. Rhodora. i: 197. pi. 9. f. 7, 8. 1899. (H. ma jus Holden). Col- 

 lins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 13. no. 602. 1899. Col- 

 lins. Preliminary Lists of New England Plants. — V. Marine Algae. Rhodora. 

 2- 42. 1900; Phycological Notes of the late Isaac Holden. — II. Rhodora. 

 7: 223. 1905. 



Plate V. fig. 60, 61. 



Plant mass mucous, tubular, dark blue-green; sheaths agglutinated, 

 forming mostly an amorphous, gelatinous, diffluent mass, from which the 

 outer extermities of the trichomes project, naked or enveloped in broad 

 ragged sheaths, or the trichomes escape entirely and become independent; 

 trichomes 25-30 mic. in diameter, not constricted at joints; apex of trich- 

 ome tapering, truncate; apical cell showing evident calyptra; cells 3-6 mic. 

 in length; transverse walls granulated; cell contents blue-green. 



Connecticut. Forming gelatinous tubular coatings on old S p a r t i n a 

 stems in ditches of a salt marsh. Bridgeport. May 1896; Cook's Point, 

 May, September. (Holden). 



263. Hydrocoleus homoeotrichus Kuetzing. Phyc. Gen. 196. 1843. Gomont. 



Monogr. Oscill. 82. pi. 13. f. 7-10. 1893. De Toni. Syll. Algar. 5: 



323. 1907. 

 WoUe. Fresh Water Algae. III. Bull. Torr. Bot. Club. 6: 183. 1877. 

 (H. phormidioides Bulnh.). Setchell. Notes on some Cyanophy- 

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



Plate V. fig. 62, 63. 



Plant mass caespitose, floating, indefinite, expanded, lead-colored or 

 black; filaments simple or sparingly branched, flexuous, more or less flex- 

 ible, entangled in tufts; sheaths lamellose, somewhat diffluent, cylindrical, 

 roughened on the surface, transversely wrinkled, with open or pointed 

 apex; trichomes 6-8 mic. in diameter, many within the sheath, parallel or 

 twisted and entangled, sometimes solitary, not constricted at joints; apex 

 of trichome gradually tapering, evidently capitate; apical cell depressed 

 conical; cells 4-5. 5 mic. in length; transverse walls frequently granulated; 

 cell contents blue-green or lead-colored. 



Connecticut. Growing in small short tufts on the posterior ends of 

 shells of living fresh water mussels (Anodonta). Trading Cove Brook, 



