226 HALF AN HOUR WITH SHELL-FISH (BIVALVES). 



itself as a prey to the first creature that may choose 

 to devour it. Some fish are thus tempted to enter, 

 but the first touch within is the signal for its 

 destruction. The shell closes not only at the side 

 but top, the latter action being effected by the 

 separation of the pointed ends ; and the captive is 

 either crushed to death, or soon perishes from 

 confinement." 



Of the oyster we do not presume to speak. In- 

 ternally and externally, it is too well known to need 

 description. But we often see attached to it and 

 not to it only, bat to other large shells, stones, &c. 

 what seems to be a miniature oyster. This is the 

 Anomia, whose thin, glassy valves mould themselves 

 to the objects they cling to. On examining the 

 lower valve, near the beak will oe seen a hole, 

 through which, in the living state, a fleshy plug 

 passes, by means of which the animal is enabled to 

 attach itself. The inexorable limits of space forbid 

 us attempting more than drawing attention to the 

 commonest shells, and those most likely to be found at 

 all rocky bathing-places. Underneath the stones, at 

 low water, may be found several minute species, as 

 Kellia, Lepton, Montacuta, &c. The former loves to 

 hide itself among the roots of seaweed, or in any 

 'sheltered situation ; the second is a thin, flat, 

 bivalve ; and the third usually adheres to the roots 

 of the larger seaweeds. Off our southern coasts, 

 also, may be found the pretty little Galeomma, whose 

 pearly white hue is sure to recommend it as an 



