304 THE INSECTS 



number 250 or more, when deposited in the nostrils or in wounds, develop into the 

 screw-worm larva, which may, by going up into the frontal sinus, cause death. 

 These larvae have twelve segments with rings of minute spines. 



Ochromyia anthropophaga (Cordylobia anthropophaga or Tumbu Fly). This 

 is an African fly whose larvae develop under the skin of man and animals. It is 

 known as the Ver de Cayor. The larva resembles the Ver Macaque, is rather 

 barrel shaped and beset with small spines. It bores its way into the skin and makes 

 a lesion like a boil which has a central opening through which the larva breathes. 



Sarcophagidae. 



These are known as "flesh flies." The most important characteristic is the fact 

 that the arista is plumose up to the mid-point, beyond which it is bare. They are 

 usually thick set and moderately large flies. 



Sarcophaga carnaria. This is a grayish fly with three stripes on thorax and 

 black spots on each segment of the abdomen. It is viviparous. The larvae gain 

 access to nasal and other cavities and there develop. Cases of death have been 

 reported. Naturally, the fly deposits its larvae on decaying flesh. . In times of war 

 all of these flies become important by reason of "maggots" in the wound. These 

 larvae are the most common ones in intestinal myiases. The mouth booklets are 

 strongly curved and separate. Each abdominal segment has a girdle of spines. 

 The anterior end is somewhat pointed. The hind stigmal plate is in a deep cavity. 



(Estridae. 



The flies of this family are usually called botflies. The mouth parts are almost 

 vestigial. They have a large head with a somewhat bloated-looking lower portion. 

 They are often rather hairy. The larvae which develop from the eggs are parasitic 

 either in the alimentary canal or the subcutaneous tissues. 



Dermatobia cyaniventris. These are large, thick-set flies about 3/5 inch long, 

 with prominent head and eyes, small antennae, and a marked narrowing at the 

 junction of thorax and abdomen. The thorax -is grayish and the abdomen a metallic 

 blue. The larvae are deposited under the skin in various parts of the body. When 

 the larvae move they cause considerable pain. At first the larva is club-shaped, 

 but later on it becomes oval. The former is called Ver Macaque, the latter Torcel. 



Hypoderma diana. The larval form of this fly has been reported three times 

 for man. It forms tumors under the skin which it is thought may reach this location 

 by proceeding in some way from the alimentary canal. 



In Hypoderma the arista is bare while in Dermatobia the upper border is plumose. 



