PI. cell . aph. 1. HYDROPHYTE. 2. Oscillat. 281 
2. Oscillator ia nigra. Black quick-moss . 
Ited black, slippery ; threads radiating, very long, stiff, 
straight, grayish yellow. 
Oscillatoria nigra, Vauch. 192. 
Conferva fontinalis, Dillwyn , 64, fig. and partly the description. 
Bottom of running waters ; becoming free in the spring. 
Threads entangled; radii about an inch long, blunt, 
oscillating very lively ; rings rather distant. 
3. Oscillatoria tenuis. Slender quick-moss. 
Bed green, slippery; threads radiating, short, rather 
stiff, straight, light green. 
Conferva gelatinosa, omnium tenerrima et minima, aquarum limo in- 
nascens, Dillen in Rail Syn. 477. 
Oscillatoria viridis, Vauclier 195. 
Conferva fontinalis, Roth Catal. 3, 195. 
Conferva limosa, Dillwyn Syn. 30 ; Engl. Bot. 2058. 
Oscillatoria tenuis, Agardh Decad. 2, 17. 
Still waters on mud ; Summer. 
Threads half an inch long, very slender ; rings very close. 
4. Oscillatoria tenuissima. Very-slender quick-moss. 
Bed velvetty, shagg}^, dark green ; threads crowded in 
ascending tufts, straight, rather stiff, pellucid, very slender. 
Conferva tenuissima, Engl. Bot. 2584. 
Oscillatoria tenuissima, Agardh Disp. ed. 2, 33. 
Warm springs, as at Bath. 
Beds very irregular ; threads about one-hundredth of an 
inch in diameter. 
5. Oscillatoria P ochracea. Ochry quick-m,oss . 
Bed thick, ochre brown, brittle; threads very slender, 
yellowish green, incumbent. 
Conferva ochracea, Roth Cat. 1, 165; Dillw. 162. 
Oscillatoria ochracea, Lyngbyc Hydr. D. 89* 
In chalybeate springs. 
Bed thick, slippery, drying to an ochry powder ; threads 
slightly bent; rings very close, intermixed with distant 
ones. 
III. 3. HUMIDA. Humida . 
Threads simple, membranaceous, bent, entangled, de- 
cumbent, free, not oscillating, nor lengthening.— Damp, 
shady places. 
f 
