108 Mr. Gray's List of British Bats. 



Icon. Tab. nost. V. f. 12 & 13. Aucta, fig. 13, b. 



Shell rather strong, semi-transparent, subglobular, flattened 

 beneath, urabilicated. Body volution scarcely so much rounded 

 beneath a^ in T, margariia^ so that the shell has an obtusely cari- 

 nated appearance. Volutions four, convex, with regular, elevated, 

 rounded belts, separated by grooves, and continued almost to the 

 apex ; these are rendered rather rough by the faint transverse 

 striae of growth, but the shell has no trace of any epidermis. 

 Spire short, elevated ; the apex raised, pointed, subacute. Aper- 

 ture and umbilicus exactly as in T, margarita. In my largest 

 specimen, the outer lip is turned outwards at its attachment to 

 the body volution, and forms a sinus ', as if to afford a passage 

 for some organ belonging to the animal. I regret extremely that 

 particular circumstances prevented me from ascertaining the pecu- 

 liarities (if any existeil) of the animal, though the specimen was 

 obtained alive. As it does not however occur in my other speci- 

 mens, I cannot attribute it to any other cause than an accidental 

 distortion. 



The whole shell is of an uniform yellowish flesh-colour, darker 

 towards the spire, lighter beneath and at the apex ; without any 

 of the metallic lustre which is so remarkable in T. margarita. 

 Aperture silvery within. Operculum horny. 



In its youngest state this shell can readily be distinguished from 

 T. margarita by the characters I have laid down ; though it is 

 certainly so nearly allied to that species that it may easily be 

 supposed to have been overlooked as a variety. 



Art. XIII. A List of the Species of Vespertilionidas 

 found in Great Britain, By John Edward Gray, 

 Esq. MM. S. 



Merret in his Pinax led the way to the study of the animals 

 of a peculiar country ; and Linnxus in his Fauna Suecica follow- 

 ing up the subject, shewed the manner in which it ought to be 

 jtreated. But this kind of study, which since the time of the latter 



