CLOSE ADAPTATION OF THE SKIN. 149 



in its old skin were also wanting when it appeared 

 in its new robes ; thus plainly proving that the 

 feet were really sheathed in the old skin completely. 

 It was just as if we had gloves on our hands and 

 were to put one finger or more between a pair of 

 sharp and powerful shears, we should, of course, 

 find that when we took off the glove we should be 

 short of one or two fingers ! 



But the hairs are not thus sheathed. The old 

 skin, if the larva was a hairy one, such as many of 

 those with which we are familiar under the more 

 popular title "caterpillars," is cast off with the 

 hairs attached to it a circumstance which makes 

 the cast skin look still more like the real larva. 

 How, then, it may be asked, does the larva acquire 

 new hairs to take the place of the old ones? 

 Were we to take a larva just before its moulting, 

 and by a sharp and delicate instrument, to slit 

 open and raise its old skin, we should soon per- 

 ceive how this has been contrived. We should 

 there perceive sundry little tufts of very delicate 

 hairs, lying down smoothly on the surface of the 

 larva's body, and arranged in certain directions, 

 with great regularity. When the old skin is cast, 

 in the course of a little time these hairs stand 



