THE ANTHRAX FLY 



A few moments of satisfaction like those I then enjoyed 

 make up for many a weary hour. 



This tiny worm, the first form or "primary larva" of 

 the Anthrax, is very active. It tramps over the fat 

 sides of its victim, walking all round it. It covers the 

 ground pretty quickly, buckling and unbuckling by 

 turns, very much after the manner of the Looper-cater- 

 pillar. Its two ends are its chief points of support. 

 When walking it swells out, and then looks like a bit 

 of knotted string. It has thirteen rings or segments, 

 including its tiny head, which bristles in front with 

 short, stiff hairs. There are four other pairs of bristles 

 on the lower surface, and with the help of these it walks. 



For a fortnight the feeble grub remains in this 

 condition, without growing, and apparently without eat- 

 ing. Indeed, what could it eat? In the cocoon there 

 is nothing but the larva of the Mason-bee, and the worm 

 cannot eat this before it has the sucker or mouth that 

 comes with the second form. Nevertheless, as I said 

 before, though it does not eat it is far from idle. It ex- 

 plores its future dish, and runs all over the neighbor- 

 hood. 



Now, there is a very good reason for this long fast. 

 In the natural state of the Anthrax-grub it is necessary. 

 The egg is laid by the mother on the surface of the nest, 

 at a distance from the Bee's larva, which is protected 

 by a thick rampart. It is the business of the new-born 



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