142 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



the flounder consists principally of Corophium, according 

 to Ashworth.* 



Sea birds also take a heavy toll of the inhabitants, and 

 Scott has some very interesting observations on this point, f 

 " When we visited the Bardsea beds, our attention was drawn 

 to a flock of gulls which were feeding on the adjacent sands, 

 and to the excreta evacuated by them These consisted of 

 well defined heaps of white, pale pink, and dark shells." 

 The white were barnacles ; the pink " henpens " (Macoma) 

 and the dark, comminuted mussels. All the heaps were 

 practically pure, showing that the birds had confined themselves 

 to one type of food at a time. Some mussels were nearly an 

 inch long, and had been regurgitated ; the rest had gone 

 through the intestine. It is considered doubtful whether 

 undisturbed cockles are available to seagulls, and that gulls 

 usually take the undersized ones left by gatherers. It is 

 suggested, that owing to shortage of gatherers (due to the war) 

 that the birds had taken to feeding on M. balthica and Balanus. 



The effect of the many shore birds that feed within the 

 tidal zone upon the surface forms of Invertebrates must be 

 considerable. 



* Report Lancashire Sea-Fish. Lab. 1899. p. 32. 

 t Report Lancashire Sea-Fish.Lab. 1915. pp. 61-2. 



