286 



Marvels of Insect Life, 



underneath it, pierces it with its fatal sting. Sure of its victim, it now walks or 

 flies away, leaving the poison to work its effect! but in a short time returns, and 

 finding it deprived of power to make resistance, seizes it again by the head, and 

 drags it away, walking backwards to deposit it in a hole or chink of a wall." If 

 the hole or chink selected is not large enough to admit the cockroach, the wasp is 

 not nonplussed : it reduces the size of its prey by biting off obstructive portions. 

 From certain observations made it appears probable that instead of feeding upon 

 the cockroach from the exterior, as other solitar}' wasp-grubs do to the caterpillars, 

 spiders, etc., with which their cell is furnished, this wasp's grub enters its prey and 



feeds within the leathery cuticle. It afterwards spins its 

 cocoon within its victim and changes to a chrysalis ; for 

 the empty cocoon is often protruding from the cockroach 

 skin. 



Perkins gives a remarkable account of a species ^ 

 he found in West Africa. This wasp enters houses that 

 are infested by cockroaches, and selects a good specimen 

 for attack — it may be four times the size of the plucky 

 wasp. A bit of a struggle ensues between the two, but 

 when the wasp has contrived to sting its victim the 

 cockroach becomes quiet and allows its conqueror to drag 

 it away to a hole. In one case that he watched, the 

 victim was carried to a keyhole and deposited therein ; 

 but the wasp, apparently conscious that its sting onl}' 

 disabled the cockroach and that the movements of the 

 latter might be sufficient to work it out of so shallow 

 a retreat, found some heavy nails and carried these to 

 the keyhole to make its prisoner more secure ! 



In most places where found the cockroach-wasp does 

 not appear to be at all plentiful ; but Lefroy states it is 

 common in the plains of India. " At Pusa this Insect 

 is purely arboreal in its habitat. The chief haunts are 

 the trunks of old peepul '■^ and fig-trees, which possess 

 numerous holes and chinks." He says it is not an un- 

 common sight to see the wasp hurrying along the tree- 

 trunk searching hole after hole for cockroaches, and 

 occasionally flying to a distant branch only to 

 return and continue the search in a few seconds. As far as observed, this species 

 confines itself exclusively to species of cockroach for its prey. The cockroach is 

 invariably bigger than the wasj). The manoeuvres employed are much like those 

 of the mud-dauber wasps in capturing spiders, though there is not so much careful 

 tact and dexterity displayed by the wasp in dealing with the cockroach, probably 

 because the latter is not armed with any poisonous weaj^ons : it has to depend 

 on its activity and the irritating spines on its legs for its defence. Often, if the 

 cockroach has wings, it takes to flight, but the wasp quickly overtakes it and alights 

 on its back, when the cockroach submits. The wasii at once thrusts its stine into 



Plwto by] ;/•'. step. F.L.S. 



Cockroach- Wasp. 



The species figured is different from 

 that shown in the plate opposite, but 

 the habits of the two are identical. 

 The upper figure shows the wasp 

 with its wings extended as in flight, 

 the lower as at rest with the wings 

 folded. Natural size. 



1 Amt)ulcx siliiriia. 



I'icii.s rcliiiiosa. 



