300 ANIMAL LIFE 



ants foster the beetle-larvae also, and, as they nurse 

 these adopted children as their own, they inflict upon 

 them a treatment which is utterly unsuited to their 

 needs, though appropriate to those of ant-larvae. 

 During the early larval stage all goes well ; the young 

 beetles, fed by the ants and feeding on the ant-eggs 

 and young, grow rapidly, but when they are about 

 to reach the pupal stage the ants bury them, then 

 unearth them, carry them to the surface and again 

 bury them. This treatment, suitable for ant-pupae, 

 is the death of the beetle-larvae, and the mortality 

 is more than 98 per cent. This result is the 

 salvation of the colony, which would be decimated 

 were the beetle to increase at the rate their foster- 

 nurses strive to attain. For it is just those nests 

 most infested by the beetle which produce most 

 stunted ants, and the perverted nursing instinct of 

 Formica sanguinea works out the salvation of its 

 race (Wasmann). 



REFERENCES 



Sharp, D. ' Insects.' Cambridge Natural History. 

 Macmillan. 



Folsom. ' Economic Entomology.' Rebman, Limited. 



Miall, L. C. ' Aquatic Insects.' Macmillan. 



Peckham. ' Wasps, Solitary and Social.' Constable. 



Latter, O. H. (Social Wasps.) 'The Natural History of 

 some Common Animals.' Cambridge Biological Series. 



Fabre. Souvenirs Entomologiques.' (In part translated 

 as Insect-Life.' Macmillan.) 



Wasmann, E. * Psychology of Ants.' Sands & Co. 1005. 



