62 Beautiful Shells. 



the shells on Plate IV., winch are the Perspective 

 Solarium (#. perspectivum), Fig. 5, the generic 

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

 spectively, that is, 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 (8. variegaturn), Fig. 6, 

 is a small but very pretty shell, somewhat rare. 

 The mollusk is remarkable on account of the 

 singular shape of its operculum, which differs from 

 that of all other species ; it is of a cone-shape, and 

 covered from top to bottom with what are called 

 membranous lamellas, 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 ojperculus is the Latin for a 

 cover or lid. 



