28o C O N C H O L O G Y. 



and the fifh performs its neceffary fun£lions 

 by that aperture ; for the valves never 

 open or feparate, as they have no hinges. 

 The bottom is the part by which they 

 affix themfelves to other bodies ; for the. 

 Balani are never found loofe, or otherwife 

 than affixed to fhells, ftones, and other fo- 

 Hd bodies. PI. I. fig. 12. PI. VIL fig. 6, 7. 



There are few fpecies of this family. 



There is another fet of marine animals 

 palled Ofcahiorns^ which though their co- 

 vering is like Shells, yet I cannot agree 

 to rank them as teftacea, for I think, 

 like the Echini, they are genera of cru-^ 

 ilaceous animals. However, Argenville, 

 Adanfon, Llnnseus, and Davila, rank them 

 with Shells ; I fhall neverthelefs keep to, 

 my opinion for. the prefent, and pafs them, 

 over with only obferving^ that, if the col- 

 ledlor thinks they are teftacea, with the 

 authors above quoted, the rank they will 

 hold is in this dlvifion, and that they will 

 form a feventeenth family. 



'a ' '^ ExPLA« 



