308 NORTH AMERICAN INSECTS. 
something more wonderful than has ever yet entered into 
the minds of the writers of fairy tales to conceive of. 
The maggots of the cheese-fly, when fully grown, become 
very hard, leave the cheese, and fall tothe ground, which 
they enter, and there remain for ten or fwelve days, after 
which they emerge as perfect insects. 
The Flea (Pulex irritans). 
This insect, with its reddish-brown uniform, thick body, 
small head and antenne, is probably as well known to per- 
sons of all classes of society and of all countries as any 
other insect in this order. It has no wings, and hence can 
not fly, but it has been placed among the flies of the order 
diptera, because its characteristics are more like those than 
any other, and it undergoes the same metamorphoses that 
all dipterous insects do, viz., depositing eggs, from which 
proceed maggots, which metamorphose into pupz, and are 
afterward transformed into perfect insects. 
The flea makes its abode principally in the fur of do- 
mestic animals, particularly the dog and cat, but it also 
dwells on foxes, mice, squirrels, bats, and pigeons, as well as 
upon the skin of man. As a general rule, its presence may - 
be avoided by paying proper attention to cleanliness, by 
keeping the rooms of our houses dry and clean, and if pet 
dogs and cats are in the house, of keeping them also clean 
and free from these troublesome blood-suckers. If beds or 
carpets have become infested with them, dogs and cats will 
prove the best remedy, because these insects are attracted 
by them, and much prefer to dwell in their soft fur. Fleas 
are more numerous in the months of August and Septem- 
ber, although no season is entirely exempt from them. 
It was formerly, and is now, believed by many persons 
that all sorts of vermin are bred from filth, and that these 
insects originate from saw-dust under floors which have been 
often wet, on which account they are so often found in 
