CHROOCOCCACER, 205 
xruginous, bluish green, steel-blue, reddish, yellowish, fuscous, 
&c. Division of the cells in three directions, the last genera- 
tion of the cells smaller than the early ones.—Rabh. Alg. Eur. 
ii., 34. 
Gleocapsa coracina. Kutz. Phyc. Gen. 174, t. 6, f. 1. 
Thallus crustaceous, very black, lubricous; single cells 
spherical, small, tegument very pale violet, distinctly lamel- 
lose, cell contents homogenous blue-green. 
Sizz. Cells *0033--004; with envelope ‘006-014 mm. 
Families ‘009-075 mm. diam. 
Rabh. Alg. Eur. ii., 35. Kirch. Alg. Schles. p. 258. 
Microcystis atrovirens, Meneg. Nost. Ital. 76, t. 10, f. 1. 
On rocks, and on boggy ground amongst moss. 
Plate DXXXI1II, fig. 3. Cells magnified 400 diam. 
Gleocapsa atrata, (Autz.) Rabh. Alg. Eur. 1., 35. 
Thallus crustaceous, mucous, black ; cells spherical small, 
tegument very thick, hyaline, homogenous, two or three times 
broader than the central cell, cell-contents pale verdigris green, 
rather granulated. 
Sizz. Cells 0035-0045 mm., with envelope ‘009-014 mm. 
Families ‘01-08 mm. 
Nag. Einz. Alg.t.1,f.1. Kirch. Alg. Schles, p. 258. 
Microcystis atra, Kutz. in Linn. viii., 875, 
On rocks in mountain regions. 
Plate LXXXTII. fig. 4. Cells magnified 400 diam. 
Glezocapsa livida. (Carm.) Kutz. Tab. 1, ¢. 21, f. 5. 
Thallus mucous, rounded lobate, broadly expanded hyaline 
dingy green, or olive brownish, cells very minute, tegument 
pale bluish, hyaline, cell contents solid dark blue-green. 
Size. Cells ‘003-006 mm.; with envelope 006-0078 mm. 
Families ‘016-05 mm. 
Rabh.Alg. Eur. ii, 36. Kirch. Alg. Schles. 258. 
Palmella livida, Carm. in Grev. Fl. Edin.; Eng. Fl. v., 897. 
Harv. Man. 178. 
Hematococcus lividus, Hass, Alg. 332, t. 82, f. 5. 
Microcystis livida, Meneg. Nost. 74, t. 9, f. 2. 
On naked ground, or amongst moss and lichens, rarely on 
rocks, on mountainous moors. 
“ Covers the overhanging limestone rocks to a great extent, sometimes 
as much as several hundred yards together. When fresh it looks like a 
blackish brown, gelatinous substance, giving the rocks on which it grows 
