408 



DIPTERA. 



tlieui by an insoluble cement on the upper surface of the two 

 or throe first rings of the body. The eggs liatch often after 

 the caterpillar has gone under ground to transform, and in 

 fifteen to nineteen da3's, or the last of September, the flies ap- 

 pear. T. (Lydella) doryphorce Riley (Fig. 328) pre3^s on the 



larviB of the Colorado potato 

 beetle. Other species of gen- 

 era allied to Tachina, accord- 

 ing to Dufour, are parasitic on 

 beetles, etc ; thus, Cassidoviyia 

 preys on Cassida, Hycdomyia 

 on Brachyderes, and Ocyj)tera 

 attacks Pentatoma ; and he 

 thinks that Chartophda floralis 

 feeds either on the food or the 

 young itself of Andrena. 

 Sarcophaga., the Flesh-fly, has a small head, with the antennal 

 bristle plumose or hairy, nalced at the tip ; the first posterior 

 cell only slightly opened, or closed, with largo teguhc and 

 stout legs. Tlie flesh-fly, Sarcophaga carnaria Linn., is black, 

 the thorax streaked with gray, and the abdomen checkered 

 with whitish. The female is viviparous, that is, the 

 larvffi hatch and live within the oviduct. The ova- 

 ries are large, arranged in a spiral manner and con- 

 tain sometimes 20,000 eggs. We have reared Sarco- 

 phaga niidipennis Loew from the cells of Pelopaeus 

 flavipes, the Mud-dauber, which had been stored with 

 spiders, the flies making their appearance on the first 

 of July, a few days before the wasps issued from the 

 cells. The parent flies had probably laid their eggs 

 in the spiders before the cells were closed by the 

 wasps. The nests were bi'ought from Texas. 

 Fig. 3-29. Musca has plumose antenna?, while in Stomoxys 

 they are pectinated. Dufour states that the allied genera, 

 Echinomyia, Gonia^ Dexia and Siphonia are also viviparous. 

 Musca (Lucilia) Ccesar Linn, the Blue-bottle fly, and Musca 

 (Calliphora) vomitoria Linn, the Meat-fly, deposit their eggs 

 (fly-blows) upon meat and decaying animal substances, and 

 during the late war were grievousl}^ tormenting to our soldiers, 



