130 THE HUMAN-FLEA. 
cylindrical, composed of head and thirteen segments, which 
are provided with long hairs; the pupa is inactive. 
Fleas, which are degraded flies—degraded by leading a 
parasitic life—are not as common in the United States as in 
other countries; at least the species attacking man is not 
universally found. Other species, however, are sometimes 
extremely troublesome, chiefly in warm regions with a sandy 
soil; here few persons are found that do not know from per- 
sonal experience these active parasites. Portions of the 
Mississippi Valley, Southern California, and Florida are not 
favorably celebrated on their account, and chasing the 
festive flea in these states is said to be a sport not limited by 
any game law. 
THE HUMAN-FLEA. 
(Pulex trritans Lann.). 
This parasite, perhaps better known than any other one, 
is a very common insect in the old world, being found almost 
everywhere, and consequently an intruder and tormenter 
that is not readily excluded from houses, no matter how 
careful and cleanly the inhabitants may be. Here in the 
United States it is not common. In fact most of the com- 
plaints made about fleas do not apply to this insect at all, 
but to fleas thatinfest dogs, cats, and other animals found in 
houses. They will attack man, however, without the 
slightest hesitation, though they do not feel at ease upon 
this new host, being used to move among dense hair; and on 
this account they are always restless upon man, move about 
constantly and so cause great irritation. 
The old statement: ‘‘who sleeps with dogs rises with 
fleas’”’ is wrong, however, as the dog flea is nowhere so 
happy as upon the dog. The female deposits in the course 
of her existence, about 800 eggs, which are large, pearl-gray 
and elongated-oval; from 12 to 20 eggs are laid in the 
cracks on the floor, in dark corners, or wherever dead or- 
ganic matter accumulates. As a general rule the female 
surrounds the egg with some blood, which, though dry long 
before the young larval flea hatches, forms part of its food; 
dead flies, which are found in such localities, are also eaten. 
