4 10 



A\TS. 



all except the few pupa- that have been forgotten or overlooked by the 

 ants, but these few are >urficient to insure the survival of Lomechnsa 

 st rn in osa in its struggle for existence. 



The singular life-histories of the Lomechusinse and other symphiles 

 have been made the basis of a number of speculations by \Yasmann. 

 The fact that the ants actually rear and feed insects that destroy their 

 brood is supposed by him to militate against natural selection, on the 

 -numd that this principle can be invoked only to account for the 

 development of characters beneficial to the species. He therefore 



FIG. 246. Cillibaiw coinata, parasitic on Lasius mi.vtns. (Janet.) A, Lasias 

 worker with three Cillibaiw in their normal position ; p, antenniform foot of Cilli- 

 bano ; B, Caster of Lasins slightly compressed to show the black scars, (n) left by 

 the mouthparts of the Cillibano ; C, Cross-section of integument around one of the 

 scars ; ina, articular membrane ; M. muscle fibres ; ca, adipocytes ; ci, intercalary cells ; 

 D, rostrum of Cillibano; li, ligula : ch, chelicerae ; pa, palps; ga. acute galea. 



believes that the ants themselves act as the selecting agency, not only 

 rearing and feeding the guests, but actually producing, by a kind of 

 unconscious cultivation, such symphilic characters as the trichomes and 

 the peculiar antennal modifications. This he calls " amical selection " 

 and compares it with man's treatment of his domesticated animals and 

 plants. The ants are induced to undertake this selection through the 

 strong appeal which the true guests make to their powerful and obses- 

 sional philoprogenitive instincts. The treatment of the Lomechnsa 

 larvse shows very clearly that the ants must regard them as their own 

 progeny, whereas the adult beetles make an additional appeal with 

 their trichomes. All this may be granted, but Wasmann goes further 

 and maintains that there is " at least a special modification of the philo- 



