106 
OSCILLATORIACEiE. 
3. Calothrix vivipara , Harv. ; spreading in continuous, velvetty strata ; filaments 
thick-walled, fasciculate at base, straight or somewhat curved, viviparous above, and 
pseudo-branched ; endochrome strongly annulated. 
Hab. Seaconnot Point, Professor Bailey (v. s. in Herb. T.C.D.) 
This appears to form a continuous stratum on rocks, like that of C. scopulorum , but 
the filaments of which it is composed are longer, 2-3 tenths of an inch long and straighter : 
more united at the base into fascicles, and furnished above with appositional branches 
which evidently rise from viviparous separations from the endochrome. Sometimes the 
endochrome seems to split or divide longitudinally ; at other times it separates trans- 
versely, the portions growing at each end and cohering laterally. The cell-wall is wider 
than in C. scopulorum. 
Certainly closely allied to C. scopulorum and also to C. hypnoides , and perhaps 
intermediate between them, connecting the extreme forms of each. It was sent to me 
by Professor Bailey as probably C. fasciculata , but it does not agree with the British 
plant so called ; and not knowing what else to do with it, being unwilling to pass it by 
altogether, I have given it a provisional locus in the genus, assigning to it the trivial 
name vivipara. It may possibly be merely a viviparous state of C. scopulorum. 
4. Calothrix pilosa , Harv. ; strata of indefinite extent, blackish or dark brown, 
pilose ; filaments densely interwoven at the base, then free, elongate, rigid, cylindrical, 
very obtuse, very flexuous, simple or slightly pseudo-branched ; cell-wall very thick, 
fulvous or subopaque ; endochrome narrow, dark green. (Tab. XLYIII. C.) 
Hab. On rocks between tide marks, Key West, W.H.H. (v. v.) 
This forms strata of indefinite extent, covering rocks in patches of a very dark 
blackish or brown colour, not in the least lubricous, and more pilose than velvetty. The 
stratum is about quarter of an inch thick ; its matrix composed of the densely inter- 
woven decumbent bases of the filaments which constitute it. These are afterwards 
erect, unconnected together, standing separately like the hairs on a fleece, very much 
curved or twisted, nearly half an inch long, rigid and not at all slimy. They are about 
the same diameter as Lyngbya majuscula ; and are scarcely attenuated at the blunt 
apex. The cell-wall or tube is remarkably thick and opaque, evidently formed of 
successive deposits, indicated by faint longitudinal striae ; and is fulvous or ochraceous 
in colour. The endochrome seldom constitutes more than a third of the diameter of 
the filaments, and is of a dull dark-green, more or less annulated. When dry the whole 
plant is rigid and harsh, and does not adhere to paper. 
This seems to be a well characterised species, different at least from any with which 
I am acquainted, and to be recognised by its shaggy, rigid pile of hair-like filaments, 
and their dark colour. Its microscopic characters are quite different from those of 
C. scopulorum. It abounds at Key West on littoral rocks. 
