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coinci'lent with a moult and change of form of the latter). From 

 this time until the hopper dies and the maggot finally quits hold of 

 its prey the sight as examined under a lens forms one of the most 

 repulsive sights that natural history can afford. 



Soon after the splitting of the hlack covering and the exposure 

 of the white maggot, a conspicuous change takes place in the 

 colour of the latter, it becoming pink or reddish. No doubt the 

 maggot, which has hitherto fed delicately without doing any 

 vital injury to its host, now proceeds to ingest the contents of the 

 hopper in an indiscriminate manner, and the change in color is 

 clearly due to this. If removed at this time from the hopper it is 

 seen to have very mobile and hard (chitinized) mouth parts, while 

 the thin and collapsed black covering still adheres some distance 

 behind the head. Growth is extremely rapid and the simultaneous 

 shrinking of the hopper, as its contents are absorbed by the para- 

 site, enhances this effect. Thus when the splitting of the black 

 covering takes place the hopper may be three or four times the 

 size of the parasite, when the latter is full fed the proportions may 

 be exactly reversed. The removal of the contents of the hopper 

 can be easily seen through parts of the cuticle. Generally early in 

 the proceedings the soft contents of one or both eyes and of the 

 head are seen to be in rapid motion, like a boiling fluid ; suddenly 

 all the pigment is removed from one eye (usually the one on the 

 opposite side to the parasite) and it becomes an opaque white 

 spot, then the other is often similarly destroyed, or sometimes 

 both more or less sinudtaneously. 



Finally the maggot, when it has finished feeding withdraws its 

 head, and may then some times be seen busily engaged in apply- 

 ing sticky matter from its mouth to its body. Its surface thus 

 becomes strongly adhesive and when it quits its prey, it is able 

 (though of course quite legless) to crawl freely over any surface 

 iiowever smooth. Soon it spins a neat white cocoon, from 

 which it emerges as an active winged insect in about i8 days. 



