54 NORTH AMERICAN ANOPLURA AND MALLOPHAGA 



er. Out of perhaps fifteen rabbits representing two species of different 

 genera, which we have examined, but one was found to be parasitized. 

 Attempts to correlate the presence or absence of parasites with the life 

 habits of the hosts have thus far proven entirely unsuccessful. It might 

 be surmised that the host species which hibernate for long periods, with 

 a very marked decrease in their body temperature, or those species which 

 spend a large part of their life in water, would be free from parasites ; 

 yet this is not at all the case. The Point Barrow ground squirrel, which 

 must hibernate for more than half its life, and the various species of seals 

 and walruses, are not at all lacking in uninvited guests. 



