PROVISION FOR REARING THE YOUNG. 121 



chamber and climb up to attack the egg, which in this 

 case also must be their first food. This rivalry 

 causes a struggle to the death. If one of the larvae 

 is notably more vigorous than its rivals, it may free 

 itself from them and survive. Let us consider the 

 fate in store for the two species. The first is much 

 more favoured, since a happy chance permits each 

 germ to produce an individual; in the second, each 

 individual which completes its evolution deprives 

 several of its brothers of life. And even this only 

 happens in the most favourable cases, for it may be 

 that not one Sitaris in the chamber may reach the 

 adult state. If the first arrival begins to absorb the 

 ^&S of the Colletes, a second hungry one may kill it 

 in the midst of its repast and take its place. But the 

 conqueror finds the provisions already reduced and 

 insufficient to enable it to reach the moulting stage, 

 at the end of which it could profit by the honey. 

 Ill-nourished and weakened, it cannot support this 

 crisis, and its corpse falls beside that of its fellow whom 

 it had sacrificed. Three or four parasites may thus 

 succeed to the same feast, and the victory of the last 

 is useless to him. His first struggle for life and his 

 first triumph are followed by irreparable defeat 

 These two examples show very well how a slight 

 difference may favour a species, and how a happy 

 quality is capable of being perpetuated by heredity, 

 since by its very nature it is destined to" be extended 

 to more numerous beings. 



Carcasses of animals stored up. — These insects lay 

 up for their offspring stores manufactured by them- 

 selves or by others. The class we are now about to 

 consider makes provision of animals either dead or in 

 a torpid condition, with more or less art and more or 



