TELLUNTA. 197 



striated, arid covered, when recent, with a thin epider- 

 mis ; the inside is smooth, glossy, and of a bluish-white; 

 the primary teeth of the hinge are very minute, the 

 lateral teeth remote and prominent. It is, commonly, 

 about the size of a large pea. 



Inhabits the rivers, ponds, and ditches, of Europe. 

 The largest are found in the Thames, and in great 

 abundance, especially at the Red-house, opposite the 

 end of Mill-bank, where, at low water, any quantity may 

 be procured, from half to three quarters of an inch in 

 breadth. Mr. Montagu has removed this, and the fol- 

 lowing shell, to the genus Cardium. 



LAKE TEJLLEN. 

 PL 47./. 5. Mr. Sowerby. 



91. Tellina lacustris. T. testa rhombea, planiuscula, glabra, umbone 



acuto. Linn. Gmel. p. 3242. 

 Shell rhombic, flattish, smooth, with an acute umbo. 

 Mull. Verm. p. 204. No. 388. Chem. Conch. 6. pi. 13. f. 135. 

 ' Encyclop. Method, pi. 292. f. 3. Mont. Test. Brit. p. 89. Linn. 



Trans. 8. p. 60. Penn. Brit. Zool. 1812. 4. p. 184. 



A smooth, thin, pellucid, horn-coloured shell, often 

 covered with a dark brown epidermis; it is broader 

 than long, and the valves near the margin are depressed ; 

 the umbo, or apex, is small, but so remarkably promi- 

 nent, as to give the shell a heart-shaped appearance 

 when seen sideways ; the hinge has a simple primary 

 tooth in one valve, and a cleft tooth in the other, with 

 lateral teeth in both valves. It is about the size of a pea. 



Inhabits the lakes and marshes of Europe. It was 

 discovered, as a British shell, by Mr. Swainson, and 



