40 . BOARD OP AGRICULTURE. 



which are open at the top, while the small end oears a cluster 

 of bristles. The habits and treatment are too well known to 

 need further description. 



The Body-louse of Man {Fediculus corporis DeGeer). 

 Figure 31. 



This species very closely resembles the last, but is usually 

 larger. It attaches itself especially to the clothing, and at- 

 tacks various parts of the body. It attaches its eggs chiefly 

 to the clothing which it frequents, especially 

 along the seams, and when the clothing is sel- 

 dom changed, as often necessarily happens in 

 time of war, it increases rapidly and becomes 

 a great source of annoyance. Many unfortu- 

 nate soldiers, who were confined in the south- 

 ern prisons and prison-pens during the late 

 war, can testify to the abundance of this par- 

 asite under such circumstances. Nor were 

 the ordinary camps free from them, especially during active 

 campaigns. 



The Crab-louse (^Phthirius pubis Leach). Figure 32. 



In the genus Phthirius the thorax is broad and not distinct 

 from the abdomen, which is flat and has eight segments, the 

 first one being composed of two united. Figure 32. 



The first pair of legs are terminated by 

 slender tarsi, not changed to grasping 

 claws, but the claws of the other two 

 pairs are large and strong. 



This species lives among the hairs of 

 the pubic regions of man, and also, 

 though much less commonly, upon the breast, arm-pits, in the 

 beard, eye-brows, and also upon the head. It sometimes also 

 clings to linen and clothing, and, not unfrequently, may be 

 found in the beds of those persons harboring them. They 

 may be destroyed by simple ointments and unguents, or by 

 the sulphuret washes described above. 



Figure 31. — Body-louse (Pediculus corporis DeG6 ), greatly magnified. From 

 Packard's Guide. 



Figure 32. — Crab-louse [Phihirius pubis Leach), much enlarged. From Pack 

 ard's Guide. . 



