310 TELLINIDiE. 



Index Testaceolog. pi. 4, f. 83. — Hanl. in Sow. Thesaur. 

 Conch, vol. i. p. 250, pi. 36, f. 16, 19, 20, 21, 22. 

 Tcllina sex radiatu. Lam. Anim. s. Vert. (ed. Desh.) vol. vi. p. 207. — Index 

 Testaceolog. Suppl. pi. 11, f. 37. 



Our description of the T. himaculata is drawn up from 

 foreign examples, the great range of variation not being 

 adequately represented Ly the scattered individuals re- 

 ported to have been taken upon our shores. The shape 

 varies from ovate to rounded ovate ; the valves are equal, 

 thick, opaque, simply convex, almost smooth, and rather 

 glossy. The diversity of colouring is infinite ; the prin- 

 cipal variations are as follows : — violet, white, orange-red, 

 rich yellow, or pinkish red (either uniform or rayed with 

 purple, the white specimens with usually two lateral in- 

 ternal spots of deep crimson) ; whitish or yellowish, with 

 narrow interrupted violet rays, Avhich often assume the 

 appearance of arrow-heads ; violet, rayed with white ; and 

 whitish, with broad fawn-coloured and narrower purplish 

 rays. The ventral margin, Avhich is often a little inflected 

 at the posterior end, ranges in the middle from merely con- 

 vex to arcuated. The sides are decidedly unequal ; the 

 front one is the longer, and tapers considerably to a rounded 

 extremity, the dorsal edge sloping greatly, but with little 

 convexity ; the hinder termination is bluntly biangulated, 

 and its dorsal edge straight, short, and but little declining. 

 The umbonal ridge is not much marked ; the ligament is 

 short, projecting, and rather large ; the beaks are acute, 

 and lean slightly backward ; the nymjihaj great and pro- 

 minent. The primary teeth are large, the lateral, which 

 are occasionally obsolete, are short, thick, and nearly equi- 

 distant. The sinus of the palleal impression is much ex- 

 panded, straight above, and bluntly rounded in front. Our 

 largest example measures two-thirds of an inch in length, 

 and full three-quarters of an inch in breadth. 



" As this species is considered by some naturalists to 

 have been erroneously introduced into our catalogues, it 

 may be stated that Mr. R. Ball has specimens of it collect- 

 ed on the coasts of Clare and Cork, and that Mr. Warren 

 of Dublin, obtained one in a living state at Ardmore, 



