Volvocina.] lyrrsoHiAL animalcfles. 153 



not to be transferred to the vegetable kingdom. Their green colour 

 leads to the suspicion that they decompose cai'bonic acid, and the 

 stomachs described b}^ Ehreuberg in the component Monads, are not 

 more distinct than the stomachs which he has represented as existing 

 in several other beings, whose vegetable nature is now generally 

 admitted. It is considered by Braim, who has paid much attention 

 to the development of inferior Alga?, that the Vlovocina are of the 

 same type with certain Zoospores, which become composite by fissi- 

 parous multiplication." — Principles of Physiology, p. 251. 



Dr. Carpenter's reviewer, in Tlie British and Foreign Medico- Chi- 

 rurgical Review, OciobQX, 1851, writes, ''"We have recently seen a 

 series of preparations by Mr. Williamson, of Manchester, who has 

 paid much attention to the development of the Volvox, which leave 

 not the slightest doubt in our minds that the entire hollow sphere is 

 oi"iginally composed of cells formed by the multiplication of a single 

 one ; and that these cells are of the same essential character with 

 those of the inferior Algae generally ; it being a part of their nature 

 to secrete a great thickness of pellucid mucilaginous matter around 

 the primardial utricle, [The delicate living membrane of the walls of 

 cells is so called by Moehl, and is considered of special importance in 

 cell-formation.] And thus the green utricles (cells), which are 

 originally in close approximation, become separated from each other 

 by its intervention, stiU remaining connected, however, by certain 

 thread-like prolongations, which Ehrenberg has erroneously described 

 as vessels." 



WTiile it is a duty due to the reader to insert the above opinions 

 on the Volvocina, my obsei-vations, for more than twenty-five years, 

 on these creatures, induce me firmly to believe in their animal 

 nature. 



Dujardin, whilst admitting the Volvocina among true animal Infu- 

 soria, would effect a difterent distribution of the genera proposed by 

 Ehi-enberg. Gyges and Chlamidomonas, would transfer to the Theca- 

 monadina, Cryptomonadina, (Ehi-.), inasmuch as they do not present 

 an aggregation of individuals enclosed by a common envelope. 

 Further, since the visual character of the red specks is not admitted 

 by the French naturalist, Eudorina and Pandorina must be combined, 

 as also Synura and Uroglena, whilst the genus Sijncrypta is ren- 



