PARASITES OP ANIMALS. 81 



cious spiral dilations of the oviducts, until hatched into small 

 larvae or maggots, when they are deposited by the mother, with 

 almost unerring instinct, upon or near decaying flesh. The 

 female flesh-fly {Sarcophaga carnaria Linn.), is said to de- 

 posit at least 20,000 of these young larvae. They are ready 

 to commence feeding at once, and grow with remarkable 

 rapidity, often becoming half an inch long in two or three 

 days. When mature, they crawl out of the flesh and change 

 to long-oval, brown pupae, in the earth or any other conven- 

 ient place, and the mature flies come forth in a few days. 

 By this rapid increase the progeny of a few pairs would in a 

 short time devour the carcass of a large animal. The blue- 

 bottle fly {Musca Ccesar Linn.), the meat-fly (Musca vomi- 

 toria Linn.), and others allied to them, are common and well 

 known species, having similar habits. The larvae of all these 

 are long, soft-bodied, footless maggots, smaller toward the 

 head, thicker and blunt behind. The larva of the blue-bottle 

 fly is represented in Figure 27. The eggs or larvae and 

 those of other similar flies are not rarely swallowed with 

 food by men and animals, and are capable of living, for a 

 time at least, in the stomach and intestine, sometimes giving 

 serious trouble. To keep them out of wounds or sores, the 

 old females should be kept away. If this cannot be done by 

 bandages, frequently washing the wounds with a weak solu- 

 tion of carbolic acid will be an effectual remedy and pre- 

 ventive. 



PARASITES BELONGING TO THE HEMIPTERA. 



The parasitic Hemiptera are all degraded, and mostly 

 wingless forms, belonging to three very different families : 

 the Cimicidce, including the bed-bug; Pediculidoe, including 

 the true lice ; and the Mallophagidce, including bird-lice, etc. 



This family, as restricted by Westwood, includes only the 

 genus Cimex, or the bed-bug and its allies. These have a 

 smoothish, oval, flat body, with a broad metathorax ; a small 

 head ; a slender, three-jointed proboscis or beak, which reaches 

 as far as the front legs when folded down, and slender, four- 



