Whelks and Conelets 255 



as Dog-winkle, and in Ireland as Horse-winkle, is one 

 of the commonest of marine snails. It may be found 

 in abundance high and dry on the rocks after the 

 recess of the tide, where, like the Rough Winkle, it 

 appears to enjoy a prolonged air-bath. Such a habit 

 should expose it to grave dangers from shore-birds, 

 but its shell is thick and stony, and in some places it 

 appears even to have developed something like pro- 

 tective coloration, but whether the cases adduced would 

 be sufficient to deceive birds is open to question. Its 

 colour is a more or less pure white, spirally banded 

 with orange, red-brown, or brown ; but the propor- 

 tions and intensity of these hues, as well 

 as the sculpturing of the shell, varies 

 greatly. The Rev. A. H. Cooke, M.A., in 

 the Cambridge Natural History, remarks 

 that " in many cases the variations may 

 be shown to bear a direct relation to the 

 manner of life. Forms occurring in very 

 exposed situations, e.g. Land's End, outer ^^'p'® °' 

 rocks of the Scilly Islands, coasts of north 

 Devon and Yorkshire, are stunted, with a short spire 

 and relativel}^ large mouth, the latter being developed 

 in order to increase the power of adherence to the 

 rock, and consequently of resistance to wave force. 

 On the other hand, shells occurring in sheltered 

 situations, estuaries, narrow straits, or even on open 

 coasts where there is plenty of shelter from the 

 waves, are comparatively of great size, with a well- 

 developed produced spire, and a mouth small in 

 proportion to the area of shell surface." The same 

 author also thinks that in some places (Newquay, 

 Cornwall, for example) the spiral bands of white and 

 17 



