OF THE HUMAN BODY. 93 



tion. It might probably reach the stomach by the 

 use of worm-eaten fruit. 



In southern countries, leeches {Hodmopis vorax) 

 are readily swallowed with water, and these are 

 said to be able to live some time in the human 

 body, causing violent internal hemorrhages. This 

 is mentioned by Larrey, and it was also expe- 

 rienced at the siege of Mahon. 



Lastly, it may be stated, that hairs, fibres, and 

 undigested flesh, passed with the fseces, have been 

 described as parasites of man. The careful practi- 

 tioner will be easily able to avoid mistakes. 



The hair of the processionary caterpillar (^Bom- 

 hyx processioned) , which forms on oaks a bag-shaped 

 cocoon often as large as a man's head , is very dan- 

 gerous to man. Nicolai's observations and re- 

 searches have proved that the caterpillar usually 

 appears during the middle of May, at first to the 

 number of from ten to twelve, on the bark of the 

 oak, from whence it wanders to the first buds and 

 twigs of the oak. Each single caterpillar is from 

 the fourth to the third of an inch in length, and 

 of the color of the bark of the oak. 



They have long, stiflf, black and white hairs or 

 bristles, and a black stripe on the back. This 



