3GO CASE OF SARCINA VENTRICULI. 



that I am much inclined to believe that the genus GONIUM, as 

 at present constituted, contains both animal and vegetable 

 species the former characterised by oral appendages, volun- 

 tary motions (eye-points ?), the latter by their simple cellulo- 

 globular formation. GoNiUM PECTORALE (Pectoralina hebraica, 

 B. St. Vincent), GONIUM PUNCTATUM, contrary to the opinion 

 of Bory St. Vincent and others, appear to be true composite 

 animals. 



But Ehrenberg has here, as in many other instances, de- 

 cided for the animal nature of organisms in which even his 

 experienced eye could not detect the characters of the family. 



Such is the case with GONIUM HYALINUM, GONIUM GLAU- 

 CUM, and probably with GONIUM TRANQUILLUM. 



These three species appear to consist merely of cells full 

 of chlorophylle imbedded in the square plate which corre- 

 sponds to the outer envelope of the NOSTOCHIN/E. 



To such forms belongs SARCINA. It exhibits no mouths, 

 no oral appendages, no visceral sacs, and its cells, instead of 

 having the gelatinous appearance so familiar to the observer 

 of the animal infusorials, are clear, transparent as if empty, 

 and have that consistency of wall characteristic of vegetable 

 structure. 



Believing SARCINA to be a vegetable, I may state, in refer- 

 ence to its characters, that they are of a kind which distinguish 

 it from all the gonioid plants at present known. It differs 

 most essentially from PECTORALINA HEBRAICA of Bory St. 

 Vincent, which, as we have already stated, appears to be a 

 true animal. It makes the nearest approach to GONIUM 

 HYALINUM, which with GONIUM GLAUCUM and GONIUM TRAN- 

 QUILLUM, even Ehrenberg himself seems inclined to hand 

 over to the botanists under the generic term GONIDIUM. 



The generic characters of SARCINA are to be found in the 



and it is interesting to observe, that those species in which they have not been 

 detected are the very species in which oral appendages apparently do not exist. 



