COCKLES. Pel 
the number of species diminishes in the ratio of 
distance. About two hundred species exist in 
collections, of which about ten are found on the 
British coasts. The shells of this genus are gene- 
rally remarkable for elegance of form, and often 
COCKLE LEAPING. 
for brilliancy of colouring. Our British species 
are among the handsomest of our bivalves. “There 
is-a pleasure,” observe the learned authors of the 
British Mollusca, “ in investigating such a group 
as this, wherein we find not only the greatest 
variety, but also the greatest distinctness and con- 
sequent certainty of specific determination.” 
