204 On the Relations of Certain 



believe, described, another species of Omalonyx, the shell of 

 which he has communicated to Governor Rawson, with the 

 name Amphibidima (^Omalonyx) felina. Indebted to Mr. 

 Rawson for an opportunity of examining the shell, we find, 

 as the author remarks in a letter accompanying the spec- 

 imens, no appreciable distinction between it and the Guad- 

 eloupe 0. unguis. 



In a late letter Mr. Guppy states that "the animal of 

 0. felina resembles in general character 0. unguis, O. par- . 

 dalina and A. patula, the latter being much larger, darker, 

 more strongly colored and more coarsely striated." 



The Guadeloupe specimens received from Gov. Rawson, 

 collected and labelled by Schramm Saccinea appendiculata, 

 are extremely interesting and not a little perplexing, indeed 

 Schramm, judging from his notes sent with them, rather 

 suggests that S. appendiculafa, depressa, and 0. unguis are 

 all one and the same species. 



Succinea depi-essa Rang (Guer. Mag., 1834, t. 55) is a 

 species as to which there seems to be much uncertainty. 

 Fischer described it, the animal and its dentition, as Pellicula 

 depressa in Act. Soc. Linn. Bord. XX, 5, to which we have 

 not had an opportunity of referring, and also in Melang. 

 Conch, p. 67, t. vi, f. 19. 



In the latter work, the jaw and teeth are thus char;»c- 

 terized : — 



" M^choire semblable a celle des Limaces, et portant uue 

 quantity de denticulations. Plaque linguale se rapprochant 

 de celles des Ambrettes. Epines medianes trifides ; late- 

 rales bitides." 



We give copy of the figure of the jaw on plate ix, fig. 4. 



Petit (Jour. Conch., 1856, p. 154) expresses the opinion 

 that S. appendiculata Pfr. is the same species, Rang's specific 

 name having priority, but Pfeiffer (Mon., IV, 804) referring 

 to Rang's figure, maintains that they are distinct. 



The character from which the specific name of Pfeiffer's 

 species is derived, he describes (Mon., II, 531) thus; '*col- 



