CHAPTER XV 



THE BLUEBOTTLE: THE GRUB 



HpHE larvae of the Bluebottle hatch within 

 two days in the warm weather. Whether 

 inside my apparatus, in direct contact with the 

 piece of meat, or outside, on the edge of a 

 slit that enables them to enter, they set to work 

 at once. They do not eat, in the strict sense 

 of the word, that is to say, they do not tear 

 their food, do not chew it by means of imple- 

 ments of mastication. Their mouth-parts do 

 not lend themselves to this sort of work. These 

 mouth-parts are two horny spikes, sliding one 

 upon the other, with curved ends that do not 

 face, thus excluding the possibility of any func- 

 tion such as seizing and grinding. 



The two guttural grapnels serve for walk- 

 ing much rather than for feeding. The worm 

 plants them alternately in the road traversed 

 and, by contracting its crupper, advances just 

 that distance. It carries in its tubular throat 

 the equivalent of our iron-tipped sticks which 

 give support and assist progress. 



Thanks to this machinery of the mouth, the 

 maggot not only moves over the surface, but 



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