CIJROOCOCCACE^E. 215 



Merismopeiia ventriculi. Rolin Veg. Par. t. I,/. 8. 



Thallus mucous-membranaceous, firm, -whitish or yellowish ; 

 families composed of numerous cells (8-4096) ; cell-contents 

 pale bluish. 



SIZE. Cells -008 mm. cliam. ; families -03--05 X -016--02 mm. 



Rabh. Alg. Eur. ii., 58. Ktichenm. Par. p. 13, t. 1. 



Merismopcedia Goodsiri, Husem. de Anim. p. 13. 



Sarcina ventriculi, Goodsir in Edin. Mecl. and Surer. Journ. 

 1842, p. 430, t. 57. Welcker in Quart. Journ. Micr. Sci. viii., 

 p. 163. 



In the human stomach, &c. 



Doubtfully included here. Recently authors have classed it with 

 Schizomycetes in preference to Algre. 



Plate LXXXV1I. fig. 6. a, cells magnified 400, 6, cells very 

 highly magnified. After Robin. 



Merismopedia renis. (Hepw.) Rabli. Alg. Eur. n., 59. 



Families composed of from 8 to 64 cells. 

 SIZE. No dimensions given. 



Sarcina renis, Hepworth in Micr. Journ. v. 1857, p. 1, 

 with woodcut. 



In the human kidneys. 



This very obscure organism, like the last, is included here with con- 

 siderable doubt. It may be said that nothing more is known of it than 

 the meagre diagnosis above given. Sarcina ossium, Stephens, Ann. Nat. 

 Hist. ser. 2, vol. xx., p. 514, is equally uncertain. 



Plate LKXXV11. Jig. 7. Cells very considerably but indefinitely mag- 

 nified. After Hepworth. 



GENUS 89. TETRAPEDIA. Reinsch. (1867.) 



Cells compressed, quadrangular or triangular, equilateral, 

 becoming subdivided into quadrate or cuneaie segments, or 

 rounded lobes, either by deep vertical or oblique incisions, or 

 by wide angular or rounded sinuses. 



" Amongst unicellular Algse falling under the class ChloropJiyttaceee, 

 forms with specially figured cells that is, otherwise than globular, ellip- 

 soidal, or cylindrical, with more or less abruptly or broadly rounded ends 

 are, as is well known, numerous ; but amongst such plants belonging 

 to the class Pkycochromacefs , so frequently found in the same situations 

 associated with the foregoing, so far as I am aware, not until recently has 

 attention been drawn to any examples of a specially figured outline. 



" It does not appear, until the genus Tetrapedia was founded by Professor 

 Reinsch for two new and singular exceedingly minute chroococcaceous 

 forms, that examples of specially figured forms were known in this family 

 of Algae. 



2 H 



