SUPPLEMENT, 



To follow at page 4 



Pleurococcus bituminosus . (Bory. Diet, in., 15.) 



Thallus mucous, brown-black, or pitch -colour, cells small, 

 rounded angular, greenish brown, 4-8 associated in families, 

 tegument scarcely broad, colourless, hyaline, indistinctly lamel- 

 lose. 



SIZE. Cells -002 mm. ; families O f l-'02 mm. 



Rabh. Alg. Eur. i., 28. 



Chaos bituminosus, Bory. Diet, iii., 15. 



Palmella bitwninosa, Meneg. Nost. p. 56. 



Protococcus lituminosus, Kutz. Tab. Phyc. i., t. 5. 



Gleocapsa bituminosa, Kutz. Spec. 224. 



On walls of damp cellars, &c. 

 Plate CXXIX. Jig. 1. Cells and families x 400 diam. 



Fleurococcus vestitus. Reinsch. Algen. Fl. p. 56. 



Cells solitary, rarely united in small families, orange ; cell- 

 membrane thick, densely invested with small hairs. 



SIZE. Cells -012--022 mm. diam. 



Kabh. Alg. Eur. i., 29. 



Acantlwcoc.cus vestitus, Lagerh. Svenska Vet. Akad. Forh., 

 1883, p. 37. 



Plate CXXIX. fig. 2. Cells X 400 diam. 



GENUS 14 bis. DACTYLOCOCCUS. l\ 7 ag. (1849). 



Cells oblong or fusiform (at first ovate-cuspidate, then ellip- 

 soid), free swimming, 2-8 associated in families, at length 

 dividing and becoming single. 



Propagation by division in one direction. 



Dactylococcus De Baxyanus. Reinsch. Contrib. t. x., /. 1. 



Cells broadly elliptical-oval, apex broadly rounded, base 

 attenuated into a hyaline pedicel, half as long as the cell, and 

 expanded at its extremity, single or twin, cell-contents intense 

 green, granulose, at length divided in 3 or 4. Cell membrane 

 thick. 



SIZE. Cells -033 x '016 mm. 



Parasitic on small aquatic crustaceans, Entomostraca, &c. 



Plate CXXIX. fig. 3. a, individuals X 400 diam. ; b, two individuals 

 X 720 diam. 



