234 INSECT LIFE xvii 



feeds on the prey. This marvel is brought about by 

 the most skilful means known to physiology. The 

 poisoned sting is sent into the nerve centres once or 

 oftener, according to the construction of the nervous 

 system, and the victim retains all which we call life, 

 except power of motion. 



Let us see if the Bembex practises this deep 

 science of murder. Diptera taken from between 

 the feet of their captor as the latter enters the 

 burrow mostly seem quite dead. They are motion- 

 less ; only in rare cases are there some slight con- 

 vulsions of the tarsi — the last vestiges of life soon to 

 be extinct. The same appearance of complete death 

 is found, as a rule, in insects not really killed but 

 paralysed by the skilful stab of a Cerceris or a 

 Sphex. The question as to life or death can, there- 

 fore, only be decided by the manner in which the 

 victims keep fresh. 



Placed in little paper twists or glass tubes, the 

 Orthoptera of the Sphex, the caterpillars of the 

 Ammophila, the Coleoptera of the Cerceris, preserve 

 flexibility of limb and freshness of colour, and the 

 normal state of their intestines, for weeks and 

 months. They are not corpses, but bodies plunged 

 in a lethargy from which there will be no awakening. 

 The Diptera of the Bembex behave quite otherwise. 

 Eristalis, Syrphus, — in short, all which are brightly 

 coloured, — soon lose their brilliance ; the eyes of 

 certain gadflies, magnificently gilded, and with 

 three purple bands, soon grow pale and dim, like the 

 gaze of a dying man. All these Diptera, great and 

 small, placed in paper twists where air circulates, 

 dry up and grow brittle in two or three days, 



