CHROOCOCCACE^E. 205 



semgirious, 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. 



Glaeocapsa coracina. Kutz. Phyc. Gen. 174, t. 6, /. 1. 



Thallus crustaceous, very black, lubricous ; single cells 

 sphserical, small, tegument very pale violet, distinctly lamel- 

 lose, cell contents homogenous blue-green. 



SIZE. Cells -0033--004; with envelope -OOG-'OH mm. 

 Families 009-'075 mm. diani. 



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 LXXX1II. fig. 3. Cells magnified 400 diam. 



Glaeocapsa atrata. (Autz.) Ralh. Alg. Eur. IT., 35. 



Thallus crustaceous, mucous, black ; cells sphserical small, 

 tegument very thick, hyaline, homogenous, two or three times 

 broader than the central cell, cell-contents pale verdigris green, 

 rather granulated. 



SIZE. 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., 375. 



On rocks in mountain regions. 

 Plate LXXXIIL fig. 4. Cells magnified 400 diam. 



Glaeocapsa livida. (Carm.} Kutz. Tab. i., t. 21, /. 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. 



Eabh.Alg. Eur. ii., 36. Kirch. Alg. Schles. 258. 



Palmella livida, Carm. in Grev. Fl. Edin. ; Eng. Fl. v., 397. 

 Harv. Man. 178. 



Hcematococcus 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 



