394 TURBININ.E. 



Ex. ]j. undulata, Chemnitz, pi. 43, fig. 4. Opercu- 

 luin, L. complanata, Cliemnitz, fig. 4, a, 4, h. Shell, 

 L. complanata, fig. 4, c. 



The shells of this group may be readily distinguished 

 by their smooth whorls, depressed spire, deep umbilicus, 

 and produced and flattened columella. 



Species of Lunella. 



complanata, Chem. mespilus, Cheni. 



crenifera, Kien. porcata, Reeve. 



granulata, Chem. porphyrites, Martijn. 



lugubris, Reeve. undulata, Chem. 



Genus MODELIA, Gray. 



Operculum with a convex, sub-central, granular rib, and 

 a sharp-edged, sub-marginal keel. 



Shell turbinate, thin, granular ; spire rather elevated ; 

 aperture sub-circular, wider than long; inner lip exca- 

 vated, with an extended, thin callus. 



Ex. M. granosa, Martyn, pi. 43, fig. 5. Operculum, 

 M. granosa, fig. 5, a, 5, b. 



The Turbo rubicimdus of Chemnitz is another species 

 of this genus, which, besides the peculiarities of the oper- 

 culum, is remarkably thin and granular on the surface, re- 

 minding one very much of Zizipltiuus among the Tro- 

 chinee. The species are from the shores of New Zealand. 



Species of Modelia. 

 granosa, Marty n. rubicunda, Chem. 



