'B2 Beautiful Shells, 



the Bhells on Plate TV,, wliicli are tlie Perspective 

 Solarium {S. loersjpectivwin) , Fig. 5^ the generic 

 name comes from sol — the sun^ and viewed per- 

 spectively^ that isj in such a position that the whole 

 top of the shell is at once presented to the view, 

 looking like a flat surface, it presents a circular 

 appearance, marked with rings and rays like repre- 

 sentations of the sun sometimes do. 



The Variegated Solarium {S.variegatum), Fig. G, 

 is a small but very pretty shell, somewhat rare. 

 The mollusk is remarkable on account of tlie 

 singular shape of its operculum, which differs from 

 that of all other species ; it is of a cone-sha^oe, and 

 covered from top to bottom with what are called 

 membranous lamella}, that appear to stand out like 

 little shelves winding up spirally. This singular 

 form of operculum has been long known to natu- 

 ralists, but it is not until lately that they have 

 discovered to what species of testacean it belonged. 

 Let us here explain that oiwrculus is the Latin for a 

 cover or lid. 



