344 Mr. G. R. Waterhouse on the Rodentia. 



(C. sordida of Roth). I also refer unhesitatingly to the Vesi- 

 culaspermce the following species, with the reproductive cha- 

 racters of which, in detail, I am less fully acquainted, but still 

 sufficiently so to enable me to affirm, without doubt or mis- 

 giving, that their proper station is with the group of Con- 

 fervas which we have been considering ; Conferva fontinalis, 

 C. Candollii, C. Borissii, and C. tumidula of * English Botany,' 

 all of which have been erroneously regarded by Harvey as va- 

 rieties of Conferva vesicata. Conferva tumidula was first in- 

 troduced into ' English Botany' under the name of Conferva 

 inflata, and with the idea of its being the Conjugata inflata of 

 Vaucher; subsequently, on the representation of Mr. Borrer, 

 so well known for the great additions made by him to this and 

 other departments of native botany, the name w r as altered to 

 tumidula, but the species was still supposed to be a member of 

 Vauchers genus Conjugata ; which, judging from the figure, I 

 should say that it most certainly is not, and under this im- 

 pression Sir J. E. Smith has appended to his description some 

 remarks on the Conjugates in general, which, as it now appears, 

 are somewhat misplaced. 



[To be continued] 



XLIII. — Observations on the Rodentia. By G. R. Water- 

 house, Esq., Curator to the Zoological Society of London. 



[Continued from p. 203.] 

 [With a Plate.] 



It is well knowm to naturalists that there exists in South 

 America many large groups of animals which are peculiar to 

 that continent or are but feebly represented elsewhere. The 

 New World monkeys all form a large section (Platyrrhini), of 

 which there are no representatives in the Old. The Edentata 

 may almost be called a New World order of mammals. Speak- 

 ing of two great divisions of the Iguana tribe of reptiles, or 

 " Sauriens Eunotes" of MM. Dumeril and Bibron, these 

 authors observe, "les Pleurodontes semblent, pour ainsi dire, 

 appartenir exclusivement au nouveau monde, ou aux Ame- 

 riques [the authors allude almost entirely to the tropical por- 

 tions] , a l'exception du genre Brachylople. D\in autre cote, 



ticed in this paper, in which it, as well as all the true Confervae, differ from 

 the conjugating Confervae. 



In admitting the existence of spores in this one species of Conferva, M. 

 Decaisne must now discard the notion of zoospores from his mind, in re- 

 ference to the reproduction of all the true freshwater Confervae with simple 

 unbranched filaments, the same phaenomena occurring in them which he 

 has noticed in Conferva vesicata {Vesiculifcra Miillena). 



