THE FLESH-FLIES 



(Family SarcopJiagida.) 



This is a large group of flies, comprising very many species, 



and as the scientific name indicates they are called "flesh-flies " 



because many of them live in the 

 larval state in the bodies of dead 

 animals. Although, as just stated, 

 many of the so-called flesh-flies are 

 flesh feeders, the group as a whole 

 is a variable one in habit. The 

 larvae of some live in decaying vege- 

 table matter and fruits, others live in 

 dung and others are practically par- 

 asitic upon living insects. One 

 genus (Sarcophila) is a parasite of 

 mammalia and even of human beings, 

 depositing its young in the nostrils 



where they cause great suffering and even death. Several species 



of this family are referred to in the 



medical literature of "myiasis" 



which means the parasitism of 



human beings by flies. 



The females of the flesh-flies 



may deposit eggs in large numbers 



or they may deposit living larvae, as 



just indicated, the eggs being hatched 



before they have left the body of the 



female. A number of famous insects 



belong to this group. The insect 



popularly known as the "screw- 

 worm fly " is well known in the 



west. It is one of the most important 



Fig. 89. Chrysomyia macellaria. 

 (Author's illustration.) 



Fig. 90. Lucilia caesar. 

 (Author's illustration.) 



of the insects which 

 affect domestic animals and its greatest damage is done in Texas 



163 



