STRUCTURE OF THE LIMPET. 301 



limpet is able to rasp through the outward tough 

 skin of the algae it feeds upon, with as much ease 

 as a joiner cuts a piece of soft wood with a sharp 

 saw. In order to have an idea of the efficiency 

 of such an implement as the limpet's tongue, let 

 the reader imagine a leather strap, of an inch in 

 breadth, set with rows of fishing hooks and points 

 of lancets alternately, and let him suppose this strap 

 so prepared to be forcibly drawn over the object to 

 be lacerated. Can any candid mind fail to admit 

 that the implement thus furnished to the limpet 

 has been adapted to the creature's wants by the 

 exercise of design, as unquestionably as any tool 

 used by the joiner is suited to the purpose for 

 which it is applied ? 



