Ilydroph. p. 200. t. 68 a .; Harv. in Hook. Br. Fl. p. 399.;
also in Manual, p. 184.; Meneghini, loc. cit. p. 114.
Hah. In freshwater pools near the coast; rivulet near
T orquay: Sir W. J. Hooker. A p p in : Captain Carmichael.
“ Fronds unattached, scattered at random in the clefts of
the rocks, globular, smooth, olive-green, diaphanous, from \ to
1^ inches in diameter, the larger ones generally compressed,
hollowed, and sometimes ruptured.” — Carmichael.
The filaments, as remarked in the description of the preceding
species, resemble those of Nostoc verrucosum in all, save
size, being larger than in th a t species. The reproductive cells
are rarely produced.
8 . N o s t o c m u s c o r u m Ag.
Plate L X X IV . Fig. 4.
Char. Frond tuherculate, subcoriaceous, variable in shape.
Filaments much curved, moniliform, exceedinglg slender.
Ag. Disp. p. 44.; Ag. Syn. p. 132.; Syst. p. 19.; Harv.
in Hook. Br. Fl. p. 399. N. muscorum Harv., in
Manual, p. 183. N. microscopicum Carm., M S .; Harv.
in Manual, p. 184. ; Meneghini, Nostochinearum Italicarum,
p. 119.
Hab. N. muscorum, on calcareous rocks, and the mosses
which cover them, Appin : Captain Carmichael. — N.
microscopicum, on exposed calcareous rocks among
mosses, Appin: Captain Carmichael. Near Youghal:
Mds Ball. Wilderness, near Clonmel: W. H. Harveg.
Clayey banks, co. A n trim : Mr. Moore.
I have examined several of Carmichael’s specimens of this
Nostoc, and compared them with others of Nostoc microscopicum
Carm., and I entertain no doubt of the specific
identity of both. All the specimens which I have received
of the former have consisted not of single fronds, but of an
ao-o'reo'ation of numerous smaller fronds of various sizes and
forms, most of them being spherical but many of them angular.
The filaments are minute, much curved, and the cells are
spherical or slightly oval. It is one of the most distinct and
beautiful species of the genus. In the smaller specimens,
there is but a single thread, which curves iu an elegant manner
throughout the frond.
9. N ostoc c^eruleum Lgngb.
Plate L X X V I . Fig. 11. Plate L X X V . Fig. 10,
Plate L X X IV . Fig. 1.
Char. Frond solitary, small, globose, solid, flu id within, at
length vesicular, mostly pale blue, sub-pellucid. Filaments
large, elegantly moniliform, much curved.
Nostoc cccruleum Lyngb., Hydroph. p. 201. No. 6. 768. /3 ;
Grev. Crypt. Fl. t. 131.; Hook. Brit. Flor. p. 400.;
Harv. in Manual, p. 185. ; Meneghini, Monographia
Nostochinearum Italicarum, p. 111.
Hab. In flowing water or in very moist places attached to
mosses, near Calender: Dr. Greville. Co. Antrim ; near
Wicklow : Mr. D. Moore. Pass of Lerry: Dr. Greville.
This species in its dried state might be readily passed over
as Nostoc commune in the first period of its growth, the filaments
of N. cccruleum according exactly with those of that
species. Notwithstanding the difference in its colour, and
perhaps in its habit also, I am not perfectly assured that it
is really distinct. The larger size of the filaments will serve
to distinguish it from Nostoc sphcericum, which in form it
resembles, as well as the difference in its colour, and its
greater mucosity, which causes it to adhere closely to paper.
Char.
10. N ostoc macrosporum ? ilfewe^A.
Plate L X X I I I . Figs. 1, 2.
Frond minute, solid, spherical, æruginous green.