102 UNIVALVES. 



this shell, that it accumulates, during its forma- 

 tion, different foreign substances, and is often 

 found covered with stones, coral, small shells, 

 and fragments of shells; on account of this 

 curious property, it has acquired the name of the 

 Carrier. It has not been ascertained how this 

 animal, during the formation of its shell, collects 

 these various substances; probably some very 

 tenacious matter is combined with its calcareous 

 secretions, so that, whatever comes in contact 

 with it before it is hardened, adheres to its 

 surface. 



Genus TURBO* Plural, Turbines. 



TURBAN-SHELL. 



Generic Character. Shell univalve, spirally 

 convoluted, solid ; shape more or less conical ; 

 aperture entire, contracted, orbicular. 



.OBSERVATIONS ON THE SHELL AND ITS 

 INHABITANT. 



The shells of this and the preceding genus 

 are often so similar, that it is difficult to define 



* Plate IV. figures 7, 8. 



