414 RAVAGES OF INSECTS. 



common in cheese, well known under the name of hoppers, 

 will be somewhat surprised to hear the illustrions Swam- 

 merdam say, " I can take upon me to affirm that the limbs 

 and other parts of this maggot are so uncommon and 

 elegant, and contrived with so much art and design, that it 

 is impossible not to acknowledge them to be the work of 

 infinite power and wisdom, from which nothing is hid, and 

 to which nothing is impossible."* But whoever will 

 examine it with care, will find that Swammerdam has not 

 exaggerated the facts. 



The cheese-fly (Piophila Casei, Fallen) is very small 

 and black, with whitish wings, margined with black. It 

 was one of those experimented upon by Eedi to prove 

 that insects, in the fabric of which so much art, order, 

 contrivance, and wisdom appear, could not be the pro- 

 duction of chance or rottenness, but the work of the same 

 Omnipotent hand which created the heavens and the earth. 

 This tiny little fly is accordingly furnished with an admir- 

 able instrument for depositing its eggs, in an ovipositor 

 which it can thrust out and extend to a great length, so 

 that it can penetrate to a considerable dejDth into the cracks 

 of cheese, where it lays its eggs, 256 in number. " I have 

 seen 'them myself," says Swammerdam, " thrust out their 

 tails for this purpose to an amazing length, and by that 

 method bury their eggs in the deepest cavities. I found in 

 a few days afterwards a number of maggots which had 

 sprung from those eggs, perfectly resembling those of the 

 first brood that had produced the mother fly. I cannot but 

 also take notice that the rottenness of cheese is really 

 caused by these maggots ; for they both crumble the sub- 

 stance of it into small particles and also moisten it with 

 some sort of liquid, so that the decayed part rapidly 

 spreads. I once observed a cheese which I had puri^osety 

 exposed to this kind of fly grow moist in a short time in 

 those parts of it where eggs had been deposited, and had 

 afterwards been hatched into maggots ; though, before, the 

 cheese was perfectly sound and entire. "f 



* Bibl. Natura3, vol. ii. p. 63. f Swammerdam, vol. ii p. 69. 



