DUNG-FLIES. 281 



half an hour engaged in this operation, and then 

 flew away. During the time, it appeared to take but 

 little notice of objects, and suffered me to place my 

 finger very near it without moving. Whether the 

 whole was the result of any accidental derangement 

 of the system, or whether the regurgitation of the 

 liquid in question was attended, as in the case of 

 rumination in quadrupeds, by any pleasurable sen- 

 sations, and effected at will, I am unable to de- 

 termine.* 



DUNG-FLIES.f 



THESE flies, though bred in dung, are in their per- 

 fect state truly carnivorous, and devour other flies 

 with greediness. Among the smaller species of 

 Anthomyia they make great havoc, seizing them with 

 their fore-feet, and then piercing their head with 

 their proboscis to suck its juices. 



LIVIA JUNCORUM. 



THE alteration of structure induced in certain 

 plants by the attacks of insects, so complete, in some 

 instances, as almost to deceive at first the most expe- 

 rienced naturalist, is extremely curious. Nothing is 

 more common than to find, during the latter part of 

 the summer, in our fens, what at first view appears 



* Since the above was written, I find a somewhat similar 

 observation recorded in London's Mag. of Nat. Hist., vol. ix. 

 p. 108. 



f The flies here alluded to belong to the genus Scatophaga of 



Meigen. 



