122 SPIDERS [CH. 



be expected, to the sedentary groups, and the most 

 elaborate but unavailing precautions are often taken 

 to render them Ichneumon-proof. The cocoons of 

 the peripatetic wolf-spiders have never been observed 

 to be parasitised. 



Even if a spider has survived these early perils 

 there are still many dangers ahead. During its 

 period of growth it has to moult some eight or nine 

 times, and the operation is at least as dangerous as, 

 say, an attack of measles to the human infant. For 

 some time beforehand feeding ceases, and the animal 

 becomes inert and apparently dead, but presently the 

 integument splits, and out struggles the spider, pale 

 and soft, and leaving behind it not only the outer 

 skin but the lining of most of its alimentary canal 

 and of its breathing tubes. Sometimes, as we have 

 said, it fails to extricate itself and dies ; quite often 

 it emerges with the loss of a limb, which will re- 

 appear reduced in size at the next moult. It is 

 necessary to go into retreat for a time after moulting, 

 till strength has returned and the integument has 

 hardened. 



But the dangers of moulting, though not negligible, 

 are insignificant beside others to which the spider is 

 exposed during its later stages, nor is a prolonged 

 dearth of food necessarily fatal, for, as we have seen, a 

 spider can fast for an astonishing time and yet retain 

 its health if it has a fair supply of water. But there 



