198 OYPE^ID^. 



part of the columella. G. lynx, Linn. (Ixi, 98). C. tigris^ Linn, 

 (Ixi, 99). 



ARiciA. Gray. Characterized by the flattened base and thick- 

 ened callous margins of the last whorl, and gibbous back. G. 

 Arabica, Linn, ilxi, 100). G. moneta, Linn. (Ixi, 1). 



CYPR^OVULA, Gray. Pyriform, oval, ventricose ; surface cov- 

 ered with revolving striae. 2 sp. Cape of Good Hope. G. 

 Gapensis, Gray (Ixi, 4, 5). 



GASKOiNiA, Roberts. (Pseudocassis, Pictet.) Form of Luponia, 

 aperture without teeth. One recent species ; and a cast. Cre- 

 taceous ; Europe. G. edentula, Sowb. (Ixi, 2, 8). 



Troschel adopts the genera Cyprsea and Aricia, and proposes 

 the following subgeneric groups, which have not been adopted 

 because the species cited as typical may be mostly connected by 

 other species having intermediate characters. 

 Cyprsa — 



Subgenus Talparia. G. talpa, Linn, 

 " Tigris. G. tigris, Linn, 

 " Lyncina. G. lynx, Linn. 

 " Mauritia. G. Mauritiana, Linn. 

 Aricia — 



Subgenus Erronea. G. errones, Linn. 

 " Erosaria, G. erosa, Linn. 

 " Monetaria, G. moneta, Linn, 



TRIVIA, Gray, (Coccinella, Leach,) Small shells with striee 

 extending over the back, where they are frequently interrupted 

 by an imipressed dorsal sulcus. 45 species, one of which inhabits 

 the temperate seas of Northern Europe, G. quadripunctafa, 

 Gra}^ (Ixi, 6, 7). " It is surprising to see with what facility the 

 expanded animal of Trivia withdraws itself — foot, mantle, head 

 and tube — through the narrow opening of the shell (Clark's 

 MS.). Like Biwcinuni nndatum it continually discharges an 

 immense quantity of clear slime. Couch saj^s that it often gets 

 into crab-pots ; so that it seems to be fond of all kinds of animal 

 food." — Jeffreys. 



PUSTULARIA, Swainson, Back with rows of pustules proceeding 

 from the dorsal sulcus, both lips ribbed clear across. G. pustu- 

 lata, Lam. (Ixi, 8, 9 ). 



EPONA, H. and A. Adams, Globular, produced at the extrem- 

 ities ; lips more less striated across. G. cicercula, Linn, (Ixi, 

 10,11). 



[Erato, Risso, 



This group, which I have placed in Marginellidse (p, 172), may 

 belong here ; it is somewhat closelj^ related to Trivia, through 

 its sculptured species, and (apparently) in dentition.] 



