164 CRYPTOGAMIA. 



Nostoc expansum, Harv. & Bail. (Tab. 6, f. 1, 2.) 



N* terrestre ; thallo expanso irregidariter lobato prasino, filis periphericis 

 arctissime intricatis densissimis, centralibus laxe imbricatis dilute 

 ceruginosis, cellulis sphcericis vel ellipsoideis ; spermatids splmricis. 



Hab. Puget Sound. 



Frond 8 inches long and 4 inches broad, perhaps formed by the con- 

 fluence of numerous individuals, very firm and leathery, uniformly 

 about as thick as a wafer, composed of jointed moniliform filaments, 

 which are very closely packed near the exterior surface, but loosely 

 scattered in a firm jelly in the interior. The articulations of the fila- 

 ments are generally small, spherical or slightly elliptical, but occasion- 

 ally larger and of a globular shape. 



A single specimen of this beautiful plant was collected near Puget 

 Sound. The earth adhering to it, containing many fluviatile Diato- 

 macece, indicates that the plant grew in a place permanently wet with 

 fresh water. 



VALPARAISO, CHILL 



Durvill^a utilis, Bory ; J. Ag. Sp. 1, p. 187. 



Sargassum cymosum, Ag. ; J. Ag. 1. c. p. 341. 



Macrocystis pyrifera, Ag.; J. Ag. 1. c. p. 156. 



Lessonia nigrescens, Bory ; J. Ag. 1. c. p. 151. 



Laurencia virgata, J. Ag. Sp. 2, p. 752. 



Ehodymenia corallina, Grev. ; Kiltz. I. c. p. 780. 



Callophyllis variegata, KiXtz. 1. C. ; J. Ag. I. c. p. 302. 



Hypn^ea musciformis, Lamour. ; Kiltz. 1. c. p. 758. 



Gymnogongrus vermicularis, J. Ag. (Tab. 6, f. 5, 6.) 



G. fronde eompressa (siccitate fere plana) lineari-angusta repetite dicho- 

 toma fastigiata, axillis obtusis, apicibus obtusis furcatisve ; coccidiis 

 frequentibus in ramis minoribus semi-immersis parvis. 



Fucus vermicularis, Tarn. Brit. Fuc. t. 221. 



