6 SOLARIIP^E. 



few; aperture oblique; umbilicus small, rounded, its margin? 

 without crenulations. 



Fossil, Silurian. United Stales ; Europe. 



Genus FLUXINA, Dall, 1882. 



" Shell porcellanous, depressed conical, umbilicate, strongly 

 carinate, with a stout umbilical rib, above which the pillar is 

 thin and emarginate ; from the umbilical rib to the carina the 

 basal margin of the aperture is deeply flexuously emarginate ; 

 above the carina it is again but less deeply emarginate, then 

 sweeps forward roundly and then slightly recedes before joining 

 the preceding whorl. 



This curious form belongs in all probability to the Solariida 1 ; 

 representing -among them Basiiissa among the Trochidaj and 

 recalling Platychisma, but with a different aperture. When 

 perfect the margin at the carina must project forward like a 

 claw, or nail, as in Schizostoma. When adult, the nuclear 

 whorls are filled up with a solid deposit of shelly matter, and it 

 is probable that there is a slight notch at the end of the umbili- 

 cal rib." West Indie*. 



( Toriniinse.) 



Genus TORINIA, Gray, 1840. 



Shell turbinately elevated or in some instances planorbiform ; 

 umbilicus typically moderate to wide, perspective, its margins 

 slightly crenulated ; lip and columella simple. Operculum cor- 

 neous, typically conically elevated, externally spiral, of numer- 

 ous volutions margined by projecting edges ; internal face 

 smooth, bearing a spirally twisted, median projection (PI. 1, 

 lig. 13). 



Tropical seas, world-wide. Fossil, Paris Basin. 



Subgenus TORINIA, Gray (restricted). 



Shell turbinately elevated ; whorls rounded, granulated, spir- 

 ally ribbed ; aperture subcircular, lip simple, columella perpen- 

 dicular and thickened. Operculum typical. 



Animal (PL 1, fig. 10) with thick, long obtuse tentacles, the 

 e} T es situated upon swellings near their outer bases ; foot very 

 large in proportion to body and shell, oval, emarginate and 

 a uri culate in front. 



