Ill 



SPHEGIDAE LARRIDES 



117 



FIG. 45. Tachytes pectinipes ?. 



Britain. 



One species of Tachytes in the south of France selects as its prey 

 Orthoptera of the family Mantidae, Insects of a highly ferocious 

 disposition, and provided with 

 most powerful front legs, 

 capable of cutting in two by 

 a single act the body of an 

 aggressor like the Tachytes; 

 the latter is, however, by no 

 means dismayed by the arms 

 of its future victim, but hover- 

 ing above the latter for some 

 time, as if to confuse it, and 

 causing it repeatedly to turn 

 its very mobile head, the 

 Tacliytcs at last pounces down 

 and instantaneously stings the Mantis in the nerve centre 

 between the formidable arms, which at once are reduced to in- 

 capacity ; subsequently the Tachytes paralyses each of the other 

 pairs of legs, and then carries off its victim. 



Larra anathema chooses mole-crickets as the viand for its 

 young, and Tachysphex panzeri selects grasshoppers of the family 

 Acridiidae. Larra pompiliformis ( = Tachytes nigcr, Fabre) some- 

 times associates itself with Sphex flavipennis (? S. maxillosus, 

 according to Kohl), forming its burrow amidst the works of a 

 colony of that species, and making use, like the Sphex, of crickets 

 for provender. This led Fabre to believe that the Larra stole 

 its prey from the Spliex, but he has since withdrawn this indict- 

 ment, and declares that the Larra obtains its crickets by the more 

 honourable, if not more humane, process of catching and stinging 

 them itself. Smith has informed us, on the faith of his own 

 observation, that L. pompiliformis uses both Lepidopterous larvae 

 and grasshoppers for its stores. 



T. (Larrada) australis, according to Whittell, plays the part of 

 a burglar, breaking open the cells of Pelopaeus (Sceliphrori) laetus 

 after they have been completed and stored with spiders ; it then 

 takes possession of the cell, and curiously enough the Pelopaeus 

 permits this, although the cell contains its egg and the store 

 of food that is intended for the use of its own young. To us 

 this seems very strange, but it is probable that the Pelopaeus 

 has no idea of the consecpuences of the intruder's operations ; 



