COMCHOLOGY. 131 



D. laciniata. The fringed Delphinula. PI. 23, fig. 5, 

 Shell depressed, umbilicus large, surrounded by large 



vaulted scales in spiral rows ; strong waved spiral striie ; 



colour reddish purple, variegated with white. 



FAMILY XV. 



TuRBiNACEA. Seven genera. 

 1. Solarium, Seven species. 



Some shells of this genus are highly valued for their beau- 

 ty and rarity. 



Shell orbicular, involuted almost in the same plane ; Pla- 

 norbis-shaped ; the spire of the right side very depressed ; 

 umbilicus large and conical, with edges denticulated or not 

 at the entrance ; aperture not modified by the last whorl of 

 the spire, which is entirely flat ; no columella. 



Solarium perspectivum. Solarium stramineum. 



S. granulatum. S. hybridum. 



S. laevigatum. S. variegatum. 



S. luteum. 

 S. -perspectivum. The perspective Solarium. PL 23, 

 fig. 4. 



Species very carinated in their circumference ; the aper- 

 ture square ; umbilicus large and crenated ; colour yellowish, 

 with brown and white bands on the sutures of the volutions. 



(S. variegatum. The variegated Solarium. 

 Species sub-carinated, aperture sub-orbicular. 



2. Trochus. The Top Shell. Sixty-nine species. 



This genus derived its name from its resemblance to a 

 top. 



The shells are marine, found in almost all parts of the 

 world ; some are smooth, but the greater number are covered 

 with knobs, spines, tuberculations, or undulations. 



The long spines on the margin of the T. Solaris are placed 

 at regular distances, and resemble the rays of the sun. Many, 



