THE ANTHRAX FLY 



segments or divisions forms a perfect ring, very much 

 curved when at rest, but almost straight when disturbed. 

 Including the head I can count thirteen segments, well- 

 marked in the middle of the body, but in the fore-part 

 difficult to distinguish. The white, soft head shows no 

 sign of any mouth, and is no bigger than a tiny pin's 

 head. The grub has four pale red stigmata, or openings 

 through which to breathe, two in front and two behind, 

 as is the rule among Flies. It has no walking-apparatus 

 whatever; it is absolutely incapable of shifting its 

 position. If I disturb its rest, it curves and straightens 

 itself alternately, tossing about violently where it lies; 

 but it does not manage to progress. 



But the most interesting point about the grub of the 

 Anthrax is its manner of eating. A most unexpected 

 fact attracts our attention : the curious ease with which 

 this larva leaves and returns to the Bee-grub on which it 

 is feeding. After watching flesh-eating grubs at 

 hundreds and hundreds of meals, I suddenly find myself 

 confronted with a manner of eating that is entirely un- 

 like anything I ever saw before. 



This, for instance, is the Amophila-grub's way of de- 

 vouring its caterpillar. A hole is made in the victim's 

 side, and the head and neck of the grub dives deep into 

 the wound. It never withdraws its head, never pauses 

 to take breath. The voracious animal always goes for- 

 ward, chewing, swallowing, digesting, until the cater- 



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