STRUCTURE OF THE BODY-LOUSE 15 



anus is at the end of the body, and just below it 

 lies the genital opening. In the female this is 

 a wide pouch, and in the floor of this are a pair 

 of stout peg-like organs the tips of which over- 

 lap and which work against one another like a 

 pair of pincers, gripping the hair or fibre of cloth 

 on which the egg is being laid. These are called 

 the gonopods (Fig. 3, 18). The copulatory organ 

 of the male is a kind of bag which when at rest 

 is inverted inside the body. On this is a strong 

 pointed organ and a small inconspicuous penis. 

 The former organ can be easily seen through 

 the skin of the lower side, lying near the end of 

 the body. 



To turn to the digestive system : the mouth 

 has no biting jaws, but in its lower part is situated 

 a long very sharp stylet which cannot be seen 

 when it is retracted inside the head. This stylet 

 (Fig. 3, 2), or stabber as it is usually called, is 

 formed of three long elements which are attached 

 parallel to each other in such a manner that they 

 form a tube with an extremely fine bore. It is 

 with this hollow stabber, which can be thrust 

 out of the mouth opening, that the louse makes 

 the wound in the skin when it feeds. The 

 mechanism of feeding is described elsewhere. 

 Above the stabber a short broad tube leads out 

 of the mouth into a chamber, the pharynx 

 (Fig. 3, 3), which has muscular walls and which 

 is the sucking pump. From this a long very 

 narrow oesophagus (Fig. 3, 4) runs to the fore- 



