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 to the ground, which 

 they enter, and there remain for ten or twelve days, after 

 which they emerge as perfect insects. 



The Flea (Pulex irritans). 



This insect, with its reddish-brown uniform, thick body, 

 small head and antennae, 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 pup^e, 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 Avhich account they are so often found in 



