DELPHINULA. 



TESTA subdiscoidea, vel subconica, umbilicata, 

 solidiuscula, anfractibus asperis aut angulatis; 

 apertura integra, rotundata, peri trem ate, con- 

 tinuo, inerassato, subreflexo ; opereulo corneo, 

 spiral!, anfractibus numerosis, confertissimis. 



Delphinula is a Genus which has been separated by La- 

 marck from the Linnean Turbines, taking T. Delphinus 

 as the type. In it he has associated shells of great diver- 

 sity of character, such as the D, laciniata, D, trigonostomay 

 Z>. conica, and Z>. Warniu The group thus formed does 

 not appear to us to be quite natural, and we would render 

 it more so by taking away D. trigonostoma and placing it 

 with the Cancellarife, its natural associates. We would 

 take away D. conica also, if we knew where to place it, 

 but it is a fossil and we are not well enough acquainted 

 with its affinities to venture an attempt at altering its 

 place. 



The name of Dolphin in English and Delphinula in 

 Latin has been given to the D. laciniata, as we suppose 

 from some fancied resemblance to a cetaceous fish. 



The Delphinulae vary in general form from nearly 

 discoid to somewhat conical ; they are umbilicated and 

 generally of a thick solid substance, the volutions few, 

 more or less rough and angular; the aperture entire, 

 round, with a continuous, thickened and somewhat re- 

 flected peritreme : operculum horny, like that of the 

 Trochi, with very numerous and closely-set volutions. 



The species which may with propriety be placed in 

 this genus are not numerous, as far as we know there may 

 be about a dozen recent and as many fossil, most of these 

 latter belonging to the tertiary beds. Several of these 

 which have been found in Normandy are most elegant 

 fossils 5 such are X). Gervillii and Z). Warniu 



Fig. 1 . Delphinula liciniata. 



2. ■ its operculum. 



3. I crenata, nobis, 



T 



