GAUZE COVERED FLASK 37 



seen moving about on the net-covered frame. These, at- 

 tracted by the odor of the meat, succeeded at last in pen- 

 etrating the fine meshes and would have entered the vase 

 had I not speedily removed them. It was interesting, in 

 the meanwhile, to notice the number of flies buzzing 

 about which, every now and then, would light on the 

 outside net and deposit worms there. I noted that some 

 left six or seven at a time there, and others dropped them 

 in the air before reaching the net. Perhaps these were 

 of the same breed mentioned by Scaliger, in whose hand, 

 by a lucky accident, a large fly deposited some small 

 worms, whence he drew the conclusion that all flies bring 

 forth live worms directly and not eggs. But what I have 

 already said on the subject proves how much this learned 

 man was in error. It is true that some kinds of flies bring 

 forth live worms and some others eggs, as I have proved 

 by experiment. Nor am I in the least degree convinced 

 by the authoritative testimony of Father Honore Fabri 

 of the venerable Company of Jesus, who asserts, in his 

 book on the " Generation of Animals," that flies always 

 drop eggs and never worms. It is possible (I neither 

 affirm nor deny it) that flies sometimes drop eggs and at 

 other times live worms, but perhaps they would habit- 

 ually drop eggs if it were not for the heat of the season 

 that matures the egg and hatches it in the body of the fly, 

 which as a consequence brings forth live and active 

 worms. 



Johann Sperling, who is usually accurate in his state- 

 ments, is also mistaken in writing in his " Zoology " that 

 worms are not engendered by flies, but arise from the 

 dung of the same, and in explanation adds with false 

 premises: Ratio huius rei animis candidis obscura esse 

 nequit; muscce enim omnia liguriunt, vermiumque ma- 



