Notes on certain Terrestrial Mollushs. 3) 



Examination of the animals of this species, and of species of 

 Proserpina, has proved the accaracy of the conclusion^ derived 

 from the shells alone. 



The Hon. Edw. Chitty^ on the receipt of copies of my papers,. 

 informed me of his previous discovery that the animal of Pro- 

 serpina is nearly allied to that of Helicina, havi^ng one pair of 

 tentacles only, with eyes at their external bases,, the head pro- 

 duced into a "snout/^ while the animal of Pi opalina is the 

 same as of Helix. 



Mr. Chitty has since verified his description of the animal, 

 and M. Poey confirms its correctness as to the number of ten- 

 tacleSy having examined the animal of the Cuban species.. 



The characters of both animal and shell are such as to sug- 

 gest the possible existence of an operculicmy but Chitty and 

 Poey have not been able to detect any such appendage. 



D'Orbigny, in Moll. Cuba I. (1841), judging from the shell 

 alone (though he failed to find an operculum), and as Poey ex- 

 presses it, " por un feliz presentimiento," included Proserpina 

 (under the generic name of Odontostoma) with Helicina and Cy- 

 clostoma, in Cyclostomidce, while Poey in his "Memorias," vol. 

 i., p. 392, having knowledge of the animal, establishes the fa- 

 mily Proserpinacea. 



The discovery of the nature of the animal of Proserpina is of 

 great interest, with especial reference to the question of the 

 value of the operculum, in any natural arrangement of 

 the Terrestrial Mollusks having two tentacles with basal 

 eyes. 



Pfeiffer, in his Monographia, and Gray in the British Museum 

 Catalogue, place all such Mollusca in the Order Pneiimonopoma^ 

 which they divide into the two sub-orders, Opisophthalma and 

 Ectophthahna (with reference to the position of the eyes behind 

 or in front of the tentacles), the former Order including the Fa 

 mily Aciculacea, and the latter Cyclosiomacea and Ilelicinacea ; 

 one of the characters of the Order, and of course of the sub- 



