TELLINA. TELLEN. 179 



the posterior side, thin, brittle, semitransparent, white but 

 not glossy, with regular but not very close striae, which in- 

 cline obliquely upwards towards the posterior edge and 

 form obtuse curves, which divaricate at their base on both 

 the sides, forming nearly right angles, so that the lateral 

 extremities appear striate in opposite transverse direc- 

 tions ; the surface is also marked with a few concentric 

 lines : beaks central, very prominent, the cartilage margin 

 running in nearly a straight direction : inside glossy white, 

 with the margin plain : in one valve a single cloven primary 

 tooth, locking into two plain ones in the other, with a 

 transverse groove extending beyond them; the lateral 

 teeth remote and very minute : diameter half an inch. 



In Falmouth harbour, and at the Land's end, Cornwall: 

 we have also found it in Teignmouth bay. v. m. 



29. Tellina suborbicularis. Orbicular Tellen. 

 .- Mya suborbicularis. Montagu, pi. 26. f. 6. 



Shell somewhat globular, semitransparent, yellowish- 

 white, often covered with a^brown skin, rather glossy and 

 reflecting metallic colors, wtth mostly a large lucid spot on 

 each side below the beaks, finely striate transversely, both 

 the sides nearly equal and rounded, with the front margin 

 rather straight, and closed all round : beaks central, promi- 

 nent, pointed, a little turned to one side ; inside chalky- 

 white, except the lucid spots of the connecting cartilage : 

 hinge with a single recurved tooth in one valve, locking 

 between two in the other, and placed immediately under 

 or rather behind the points of the beaks, besides a lamellar 

 and somewhat remote tooth place?r longitudinally in each 

 valve : length three eighths of an inch ; breadth half an 

 inch. 



From its groat similarity to T. cornea, and its being fur- 

 nished with lateral teeth, we have no hesitation in placing 

 it in this genus. 



Devon coasts, and Dublin bay ; often imbedded in hard 

 limestone, and frequently among masses of the Serpula tu- 

 bularia : we have also sometimes found it inclosed in the 

 valves of the Area perforans. v. v. 



30. Tellina cornea. Horny Tellen. 



Lister, pi. 159, f. 14 Pennant, pi. 52. f. 3 Da Costa, 



pi. 13. 



