I 4 4 THE HAUNTS OF LIFE 



gins to form within the egg. For every ani- 

 mal in its early life tends in a greater or less 

 degree to repeat in its personal history some 

 of the stages that have been gone through in 

 the history of its race, and much of this can 

 be made out by a careful study of the stages 

 that appear, often to disappear again very 

 quickly, in the earlier period of the building 

 up of the body of the individual. 



The same thing is true to some extent of 

 habits, and, in particular, many animals have 

 an impulse to go back at the breeding-season 

 to bring forth their young in the place where 

 they themselves first began life. Therefore, 

 when we find an animal leaving the haunt in 

 which the greater part of its life is passed, 

 to bring forth its young in quite a different 

 one, we have good grounds for believing that 

 its ancestors once had their home in the haunt 

 to which it returns. 



But there is a difficulty here which must be 

 faced. There are some cases in which the 

 youthful stages are passed in a haunt which 

 was certainly not the original headquarters. A 

 good illustration of this may be found in in- 

 sects like May-flies and Dragon-flies, Caddis- 

 flies and Alder-flies, Gnats and Harlequin- 



