CARNIVOROUS INSECTS 



"3 



broad strong head is therefore at once apparent. After going 

 all round in this fashion it moves inwards and works on a 

 narrower circle, and so goes on till a conical pit is excavated, 

 at the bottom of which it buries itself, the front part of the head 

 only projecting. If now an unfortunate fly, or, still better, an 

 ant, steps over the margin of the trap, it will begin to lose foot- 

 hold, sliding gradually downwards, the descent being rendered 

 still more easy by the ingenious ant-lion, which pitches sand on 

 the prospective meal. Once seized by the aggressive -looking 

 mandibles there is no chance of escape, for a special arrange- 

 ment exists by which the juices of the prey can be sucked with- 

 out any necessity for leaving go. The beginning of the food- 

 tube is in the form of a muscular suction-pump to which a groove 

 on the under side of each mandible leads, and in this groove 

 the long and slender first maxilla of the same side works back 

 and fore like a piston. After finishing its meal the bloodthirsty 

 larva pitches the shrivelled remains of its victim to some distance, 

 partly, perhaps, for sanitary reasons, and it may be to prevent 

 other available wayfarers from taking alarm. It is interesting 

 to note that certain cousins of the Ant- Lion, though similar in 

 appearance, do not dig pit- 

 falls. These, however, are 

 active in their habits and pro- 

 gress in the usual direction, 

 forward and not backward. It 

 is supposed that they remain 

 in ambush, hidden in dark 

 corners, rushing out when a 

 favourable opportunity offers. 

 Mantis-like Net-Wings. 

 — Equally interesting, though 

 less familiar than the Ant- 

 Lion, are the Mantis-like Net- 

 Wings {Mantispides) (fig. 388), constituting a small group of which 

 the species are mostly found in the hotter parts of the globe, 

 though some are natives of South Europe. The great peculiarity 

 of the adult insect consists in the structure of the strong fore-legs, 

 which, as in the praying mantis, &c., among the Orthoptera, are 

 attached close to the head and specialized into a very effective 

 fly-trap. The middle section of each leg is studded with strong 



VOL. II. 40 



Fig. 388.— Mantis Net-Wing (Mantispides) 



