28 
the valves toothed or plaited. Hinge with four teeth on 
each valve: the two cardinal approximate and oblique, 
articulating crosswise with the corresponding teeth of the 
other valve; the two lateral teeth distant, entering. 1 he 
ligament is external and very short; and there are two 
faint muscular impressions. 
* C. EDULE. Turt. Lin. Pen. Brit. Zo., pi. 50, fig. 41- 
Mont. Test. Brit., vol. 1, p. 76, Flem. Brit. An., p. 422- 
Common Cockle. Common in harbours that have a streatn 
of fresh water; from whence they are taken in abundance, 
and carried to market. 
This shell varies so considerably, as almost to raise the 
suspicion of a difference of species. In its younger state it is 
about equal-sided, the ridges smooth; but when fully grown 
in an undisturbed situation, the hinge is nearer one end, lh e 
opposite margin produced, and the ridges thickly and regu- 
larly covered with raised transverse edges. A considerable 
quantity in this state, of large size, aud mixed with Vene- 
rirupis Decussata, V. Virginea and others, were found with 
other ancient animal remains, in the stream work of Lower 
Pentewan, near St. Austle. 
* C. ECHINATUM. Turt. Lin. Mont. Test. Brit., vol. L 
p. 78. Flem. Brit. An., p. 420. Prickly Cockle. 
uncommonly taken in the Trawl. 
* C. TUBERCULATUM. Mont. Test. Brit., vol. I, p. 72, 
and vol. 2, p. 568. Flem. Brit. An., p. 421. The loose 
valves are scattered along our shores; and in some place* 
in abundance, as in Lantivet. bay, east of Fowey. 
C. CILIARE. Turt. Lin. Mont. Test. Brit., vol. 1, p. 80- 
Fleming supposes this to be the young state of C. AcU- 
lealum. Pen. Brit. Zo., vol. 4, pi. 50, fig. 39. Mont- 
Test. Brit., vol. 1, p. 77. A shell so slight and fragile ® 9 
this, will scarcely be found abundant on the shore; bene® 
the only place at which I have discovered it, is Pentew*>°- 
* C. EXIGUUM. C. Pygmenm. Turt. Lin. C. E. Mont- 
Test. Brit., vol. 1, p. 82. Flem. Brit. An., p. 422. Tin 9 
shell belongs to Lamark’s sub-section, in which the vaK® 
has a carination or angle, dividing the surface into two 
unequal longitudinal spaces. Not uncommon near l 0, ' , 
water mark. 
* C. MEDIUM. Turt. Lin. Mont. Test. Brit., vol. 1, p. 8®’ 
Flem. Brit. An., p. 422. This shell bears much resen 1 ' 
blanoe to the last; but it is larger, and without tubercle 9 
or spines, I found it in abundance in the soil taken U P 
for the purpose of deepening the harbour, at Falmouth. 
C. NODOSUM. Mont. Test. Brit., vol. 1, p. 81. “W' tn 
a flat suborbicular shell; colour rufous while, with 24 rib*’ 
covered with close set, obtuse tubercles. Inside wild® 
