254 



MOLLUSCA. 



/ :^m 



THE SPOTTED HORSE- FOOT (Tridacne Maculata}. 



strong are the tendons of its cable, that they can 

 be severed only by repeated strokes of an axe. The 

 flesh, though tough, is eatable, and a single one is 

 said to be a plentiful meal for a hundred and fifty 

 men. 



Many of the Bivalves have, however, a more 

 extended sphere of action, possessing the power of 

 changing their place, though in general but slowly. 

 But in the genus 



Cardium,* the Cockle, 

 more agility is manifested, than we should at first 



* KapStx, kardia, a heart. 



