464 THE COMMOK LOUSE. 



are no feelers, and the antennae are about the 

 length of the thorax. The abdomen is somewhat 

 flattened j and the legs, which are six in number, 

 are formed not for leaping, but running. 



Lice live on animal juices, which they extract 

 from living bodies by means of their sucker. The 

 larva and pupa resemble the perfect insect. 



THE COMMON LOUSE*. 



When we examine the human Louse with the 

 microscope, its external deformity strikes us with 

 disgust. The fore part of its head is somewhat 

 oblong, while the hind part is rounded. The skin 

 is hard and transparent, with here and there a few 

 bristly hairs. On each side of its head are two 

 antennae or horns, jointed, and covered with bristly 

 hair ; and behind these are the eyes, which are 

 large and black. The neck is short, and the breast 

 divided into three parts ; on each side ot which are 

 placed three legs, armed at the end with small 

 claws, by which the animal lays hold of different 

 objects. The trunk, or proboscis, is generally con- 

 cealed in its tube : this is very sharp, and furnished, 

 toward its upper part, with a few reversed prickles. 

 By means of this the Louse feeds ; and, when it is 

 engaged in sucking any animal, the blood may be 

 seen, through the transparency of its external co- 

 vering, to rush like a torrent into the stomach. 

 Through this its stomach and intestines are also 



' Pediculus hamarius Linn. 



