ANIMAL PARASITES. 



147 



This louse is commonly known as the 

 Pediculus "crab-louse," from its resemblance to a 

 Pubis. crab. Its nits are attached to the hairs 



quite close to the skin. Oftenest the nits 

 are only found in the pubic or adjacent hairy parts, 

 but they may be present on the hairs of the chest, the 

 axillae and even on the eye-brows. 

 Where the insect bites, a minute 

 slate-colored lesion results which 

 itches intensely. 



The parasite is ordinarily con- 

 veyed from person to person 

 during sexual congress, but sleep- 

 ing with a person harboring the 

 parasite may be the means of 

 contracting it. 



The "toilet" has also been 

 held responsible. 



Both the parasite and its nits 

 are quickly killed by smearing 

 the affected parts with mercurial (blue) ointment. 



The clothes-louse makes its home in the 

 Pediculus seams of the clothing and underwear. Its 

 Vestimenti. bites cause itching. Scratch-marks over 

 the back and around the waist-line usually 

 evidence its presence. Boiling or steaming the cloth- 

 ing, or hot ironing, are easy means of ridding a person 

 of the parasite. 



Fig. 23. — Pediculus vesti- 

 menti: X io» circa. (Tyson, 

 after Braun.) 



