38 RAMBLES IN SEARCH OF SHELLS. 



noted was that, although the so-called Unio Richensis 

 was highly iridescent in its lining, this was not the 

 case with Anodonta cygnea. No specimens of pic- 

 torum were found there. 



Mussels furnish food to many animals, hut espe- 

 cially to otters, rooks, and crows. Numbers of these 

 shells have been found in an otter's haunt, with the 

 ends bitten off, and evident marks of teeth upon the 

 broken fragments, the position of the shells indi- 

 cating that the otter, after having crunched off one 

 end, had sucked or scooped out the mollusc in much 

 the same way as those who are partial to shrimps 

 dispose of that esculent crustacean. Books and crows 

 we have repeatedly observed in search of a dinner of 

 mussels ; and very systematically they set to work. 

 On the muddy banks of the Thames at low water, 

 and along the margin of the Brent, especially in 

 time of drought, numbers of mussels may be found 

 which have been opened by these birds. Should 

 the shell occasionally prove a little too strong for 

 them, they will fly up into the air with it and drop 

 it from a height on hard ground, following it in 

 the descent to find it broken, or to repeat the 

 manoeuvre until at length they get at the contents. 



