d. Filaments brown, brittle, not coriaceous.
24. Osc il lato ria D ic k ie i Hass.
Plate L X X I I . Fig. 13.
Char. Stratum light chestnut, gelatinous, glossg. Filaments
lo7ig, straight, hrittle, rather thick. Striæ visible, subdistant.
Hab. Pools of fresh water near the sea, Aberdeen : Dr.
Dichie.
The colour of this species is so peculiar as at once to distinguish
it from all others which have been described. This
colour is preserved in drying ; the filaments are of nearly the
same diameter with those of O. tenuis, but they preserve their
calibre Avhen dried. Several fine specimens of this plant
were sent me by Dr. Dickie, and which have undergone no
change since they have been in my possession, now some
weeks.
e. Filaments collected into close erect tufts.
In the species of this division of the genus there would
appear to be an evident transition to Rimdaria, the filaments
in one, 0 . lucifuga, and perhaps in the others, being subulate,
and which circumstance induced me, as well as its erect
habit, to place that species in the genus Rivularia. I am now
satisfied that it should either remain in the division of the
genus Oscillatoria in which it has been placed by Mr.
Harvey, or tha t Kiitzing’s Symploea ought to be adopted for
the reception of the species of this division of Oscillatoria.
Kiitzing thus defines the genus :
Trichomata adscendentia vaginata in fasciculos erectos, basi
confiuentes, coalita ; vaginæ ex membrana simplicima, hyalina,
(nee striatæ nec lamellosæ) formatæ.
25. Osc il la to r ia F r ie s i i Ag.
Char. Stratum bright green, bristling with the elongated, erect,
tooth-like fascicles o f filaments.
Sc-gtonema Bangii Lyngb. Dan. t. 28. Oscillatoria Bangii
Carm. M S .; Grev. Fdin. p. 303. O. Friesii Harv.
Hook. Brit. Fl. 373.; Harv. in Manual, 162.
Hab. On mosses in shady subalpine situations, near Fdln-
burgh : Dr. Greville. Appin : Capt. Carmichael. Killarney:
W .H .H arv eg. Co. K erry: Mr. Andrews.
“ Stratum two or three inches broad, bright æruginous
green. ^ Filaments closely interwoven into erect, elongated,
tooth-like fascicles, an inch or more in height, pale green ;
under the microscope annulated within, with a broad limb or
border. Well marked by its erect spinulose habit.” — Harv.
The filaments in the dried state are fiaccid, long, and apparently
of equal diameter. Striæ scarcely conspicuous, rather close.
26. O sc il lato ria lu c ifu g a Harv.
Plate LX V . Figs. 5, 6.
Char. Stratum blackish green, bristling with minute toothlike
fascicles o f filaments. Filaments subulate.
Calothrix lucifuga Carm. MSS. ; Harv. Hook. Br. Flor.
p. 373. ; Harv. Manual, p. 162.
Hab. “ On the decayed trunk of an alder, lying in a ravine,
and buried under a heap of rubbish,” at Appin : Capt.
Carmichael.
“ Stratum spreading, dull, blackish green, bristling all over
wfih minute erect fascicles about one-third of a line high.
Filaments thickish, fiexuous, strongly agglutinated together,
annulated within, pale yellowish. Almost like the last species
in miniature’’(iferw.), of which it may be but a variety.
27. Osc il lato ria ten uissima A^.
Char. “ Dark green, ascending, tufted. Filaments simple,
cglindrical, even, without ang visible joints.” — Harv.
O. tenuissima Sm., Fng. Bot. t. 2584. ; Harv. in Hook. Br.
Fl. 373.; Harv. in Manual, p. 162.
e 2