NOSTOCHINEiE. 
115 
This is unknown to me. It seems to be closely allied to the preceding species, if it 
be distinct. The plicae and reticulations observed do not appear to be characters of 
much value for the discrimination of species among these gelatinous plants. 
6. Nostoc microscopicum , Carm. ; fronds densely aggregated, very minute, globose 
or oblong, immersed in a blackish crust ; filaments few. Carm. in Hook. Brit. FI. 2, 
p. 399. Harv. Man. Ed. 1 ,p. 184. N. muscorum , Hass. Br. Fr. Wat. Alg. p. 292, 
t. 14, jig. 4. 
Hab. “ Stones in a small stream, Baffin’s Bay, Dr. Sutherland , fide Prof. Dickie. 
I have not seen American specimens. In Britain this species grows among mosses 
on exposed calcareous rocks, but not in water. The above specific character is taken from 
the British plant. The fronds are rarely more than the tenth of an inch in diameter, 
and contain two or three beaded filaments lying in a copious transparent jelly. 
7. Nostoc jlagelliforme , Berk, and Curt. ; terrestrial ; frond cartilaginous, linear, 
very narrow, compressed and often channelled, much branched, irregularly dichotomous ; 
branches solid, densely filled with moniliform curved threads. Berk, and Curt. 
No. 3809. 
Hab. On naked aluminous soil, at San Pedro, Texas, Mr. Charles Wright (v. s.) 
Fronds several inches in length, half a line in diameter, lying prostrate on the 
surface of the soil, much branched in an irregularly dichotomous manner : branches 
exactly linear, compressed, often channelled on one or both sides, thinned in the middle 
and incrassated to the edge. Substance firm and elastic, cartilaginous, solid, densely 
filled with moniliform, curved or curled, interlaced threads, which are set longitudinally 
in the frond, and lie nearly parallel to each other. Colour dark olive. 
A very curious and most distinctly marked species, differing from others of this 
genus, much in the same manner that Chcetophora endivicefolia does from the ordinary 
globose forms of Chcetophora. 
