.380 THE SENSORIAL FUNCTIONS. 



they are to be placed at an after period, would 

 of itself, were it a solitary instance, be well fitted 

 to call forth our admiration. But as we study 

 each department of the animal economy in 

 detail, the proofs of design in the adaptation of 

 organs to their respective purposes multiply 

 upon us in such profusion, that we are apt to 

 overlook individual instances, unless they are 

 particularly brought before our notice. How 

 often have we witnessed and profited by the 

 rapid renewal of the cuticle, when by any acci- 

 dent it has been destroyed, without adverting 

 to the nature of the process which it implies ; or 

 reflected that the vessels of the skin must, on 

 all these occasions, supply the materials, out of 

 which the new cuticle is to be formed, must 

 effect their combination in the requisite pro- 

 portions, and must deposit them in the precise 

 situations in which they are wanted ! 



Different animals present remarkable differ- 

 ences in the thickness and texture of the cuticle, 

 according to the element they are destined to 

 inhabit, and the situations in which they are 

 most frequently placed. Provision is in many 

 cases made for preserving the cuticle from the 

 injury it would receive from the long continued 

 action of the air or water ; for it is apt to become 

 rigid, and to peel off", from exposure to a very 

 dry atmosphere ; and the constant action of 

 water, on the contrary, renders it too soft and 

 spongy. In order to guard against both these 



