32 GENERATION OF INSECTS 
could not escape in spite of all their endeavors, five or 
six days after birth turned as usual into as many eggs 
[pupae], some of red and some of black color, and not 
of the same size; subsequently, at the proper time, dif- 
ferent kinds of flies came out, green flies, big blue flies, 
black flies striped with white, and others resembling the 
marine locust and winged ants, which I have described. 
Besides these four kinds I also saw eight or ten common 
flies, such as daily hover and buzz about our dinner tables. 
Having on the twentieth day noticed that among the 
larger eggs [pupae], there were some still unhatched, I 
separated them from the others in a different vessel, and 
two days after there gradually came out of them some 
very small gnats, the number of which after two days 
had greatly exceeded the number of eggs [pupae]. I 
opened the vessel and having broken five or six of the 
eggs [pupae] I found them so packed with gnats that 
each shell held at least twenty-five or thirty, and at most 
forty. 
I continued similar experiments with the raw and 
cooked flesh of the ox, the deer, the buffalo, the lion, the 
tiger, the dog, the lamb, the kid, the rabbit; and some- 
times with the flesh of ducks, geese, hens, swallows, etc., 
and finally I experimented with different kinds of fish, 
such as sword-fish, tun, eel, sole, etc. In every case, one 
or other of the above-mentioned kinds of flies were 
hatched, and sometimes all were found in a single animal. 
Besides these, there were to be seen many broods of small 
black flies, some of which were so minute as to be 
scarcely visible, and almost always I saw that the decay- 
ing flesh and the fissures in the boxes where it lay were 
covered not alone with worms, but with the eggs from 
which, as I have said, the worms were hatched. These 
