270 THE SCHOOL OF REAUMUR 



had started, and which had attracted the notice 

 several other naturalists during the forty years' intervi 

 between the Continuatio Arcanorum and the Histoii 

 des Pucerons. He showed that both the winged ai 

 the wingless aphids may be viviparous ; Leeuwenhoe 

 had concluded too hastily that the wingless forms ai 

 immature insects, destined afterwards to acquire win^ 

 K^aumur was aware that the unfertilised females 

 bear young, and he endeavoured to rear successi^ 

 generations of viviparous aphids, but was accidentallj 

 hindered. Leeuwenhoek had concluded from his o^ 

 observations that ants devour aphids, and are the gre« 

 natural check upon their inordinate increase ; E^aumi 

 however, confirmed and corrected the view which Goedai 

 had put forth long before and which Frisch had defended! 

 he showed that when ants seek out aphids, it is n( 

 usually in order to prey upon them, but to drink thei 

 sugary exudation. He found small red ants, probabl] 

 Formica rufa, dwelling underground in company witl 

 grey aphids. All honeydew, E^aumur maintained, 

 the product of aphids, a statement which has been con] 

 firmed by later observers. He showed that a fluid 

 exuded from the tubes which in most aphids stand u] 

 from the hinder part of the abdomen, but he could giv( 

 no account of the use of the fluid. ^ 



Keaumur's Aphis-studies enabled him to suggest to 

 his young friend, Charles Bonnet, the inquiry which 

 has immortalised his name, and in the last volume of 

 the Histoire des Insectes ^ Keaumur had the satisfaction 

 of noticing Bonnet's discoveries with warm praise. 



^Bonnet {Traits d^Insectologie) was the first to observe that aphids defend 

 themselves by directing the extremity of the abdomen (which bears the 

 tubules) towards an enemy. 



2 Vol. VI, pp. 523-568. 



