MALACOZOA. TROPIOPODA. LAMELLIBRANCHIATA. 279 



GENUS 4. TELLINA. 



Animal roundish, subtrigonal, or oblong, generally 

 much compressed. The lobes of the mantle thin, free 

 before, and bordered with tentacular appendages, united 

 behind, but with an aperture for the very elongated 

 tubes. Mouth small. Branchiae unequal. Foot much 

 compressed, sharp-edged, pointed. Adductor muscles 

 large, and widely separated. 



Shell suborbicular or elongated, more or less inequi- 

 valve, inequilateral, concentrically striated. Umbones 

 small, rather pointed. Hinge generally with two small 

 divergent teeth, leaving between them a triangular de- 

 pression, in one valve, and a single small tooth, but 

 sometimes two teeth in the other ; the lateral teeth 

 obsolete, merely forming a thickened margin. Anterior 

 end larger and rounded, posterior short, angular, and 

 bent to the right. Muscular impressions widely sepa- 

 rated. Ligament external and prominent. 



The Tellmae reside in sand or mud, along the shores. 



1. Telllna solidula. Little Thick Tellina. 



Shell orbiculato-trigonal, convex, thick, transversely obso- 

 letely rugoso-striate, pinkish, with redder concentric bands, 

 the inside carmine ; the umbones behind the middle, the frontal 

 slope convex, the dorsal slightly so, and forming an angle with 

 the lower outline ; the cardinal margin thick ; two very small 

 cardinal teeth in each valve. Length ten-twelfths, height nine- 

 twelfths. 



The form varies, some individuals being longer and thinner, 

 others nearly orbicular, very thick and convex. The colour 

 also varies, individuals being white, yellowish-white, or dull 

 yellow, with deeper bands, the inside white, yellow, or red. 



Common in sandy and gravelly places near low-water mark. 

 Frequent, of large size, very convex, but with the surface 

 dull and coarse, in the muddy Estuary of the Ythan ; also in 

 that of the Dee, where however it is confined to a few spots. 

 Very frequently cast on the beach. 



Tellina carnaria. Penn. Brit. Zool. iv. 88. PI. 49. f. 32. Tellina 

 solidula. Mont. Test. Brit. 63.-r-Psammobia solidula. Flem. Brit. 

 Anim. 438. Tellina solidula. Lamk. Syst v. 533; Ed. 2. vi. 206. 

 Psammobia solidula. Turt. Brit. Biv. 95. PI. 8. f. 2. 



