ALGH FROM THE WEST INDIES. 265 
“ Crass. fil.” (as used in this paper) = the diameter of the sheith 
containing the trichomes. 
“ Crass. trich.”’= the diameter of the cells without the sheath. 
Class CONFERVOIDER% ISOGAME. 
Ord. ConFERVACEE. 
1. Conrerva BomBycina, 4g., forma mrtnor, Wille. (Om 
Hvileceller hos Conferva, p. 21, t. 1. figs. 36-40, t. 2. figs. 55, 56.) 
Crass. fil. 6°5-7°5 p. 
Hab. In cold, warm, and hot streams, crater of Grande Soufri¢re, 
Dominica. Nos. 880, 883, 884, and 908. 
2. Rurzoctontum BEraGRentanum, Hauck in Nordst. Freshw. 
Alg. of New Zeal. §& Australia, p. 17. Var. DOMINICENSE, nov. 
var. (Pl. XIV. figs. 17-24). 
Var. filamentis dense intricatis, tenuior, articulis diametro 
2-3plo longioribus; membrana cellularum 1 p» crassitudine. 
Crass. cell. veget. 9-10 p. 
Hab. In hot stream in crater of Grande Soufriére, Dominica. 
No. 880. 
In the more densely intricate portions almost every cell emitted 
a short lateral branch, usually consisting of one cell. 
Ord. CHROOLEPIDES. 
3. TRENTEPOHLIA OpoRATA, Wittr. (Scand. Victer. t. 4. p. 16.) 
[Chroolepus odoratum, Ag. Syst. Aly. p. 35.] 
Crass. cell. veget. 12-20 1; crass. zoogonidang. 33-37°5 pu. 
T. zoogonidangiis lateralibus, interdum terminalibus, subglo- 
bosis, sessilibus (hine inde pedicellatis). 
Hab. On bark, Bow-wood Hills (1580 ft.), St. Vincent. 
(8-12-91.) No. 23.—On trees, Government House, St. Vincent, 
900 ft. (10-12-91.) No. 27. 
4. T. vintosi, De Toni. (Syll. Alg. i. p. 239.) [Chroo- 
lepus villosa, Auetz. Phyc. gener. p.. 234; Species Algarum, 
p- 428.] 
Crass. cell. veget. 18-23 p. 
Hab. On rocks, Soufritre, Dominica. (2-7-92.) No. 20. 
LINN. JOURN.— BOTANY, VOL. XXX. U 
