470 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



the middle of March. Five specimens of Sarcophaga sp. emerged, 

 these appeared on March 30, April 2, 10, 13 and 15. 



Other large supplies of larvae and pupae collected in the fall showed 

 very similar results as regards emergence; the adults of P. regina 

 emerge when the temperatures are moderate in fall and spring but the 

 Lucilias do not appear till later in the spring. 



The seasonal occurrence of infestations of P. regina in Texas appears 

 to range from the beginning of lambing, which is about December 1, to 

 shearing time. Shearing is begun in April and extends to June, 

 the ewes being the last to be shorn. The cessation of injury in early 

 summer is due to the dimunition of the number of Phormia and more 

 especially to the abolition of favorable places for attack by the removal 

 of the wool. 



Life-History AND Habits of Phormia regina 



So far as we have observed, Phormia regina breeds exclusively in 

 animal matter or in substances in which animal matter is intermixed. 

 The species is found very generally distributed where it normally 

 occurs. Specimens have been observed far from any habitation, and 

 it is also very commonly met with in the center of large cities. While 

 the flies visit freshly killed animals and fresh blood, they show a special 

 predilection for meat which is in a decaying condition and consequently 

 having a strong odor. It is probably the odor of the soiled wool, 

 especially when some blood is present, which attracts the flies to the 

 living sheep. This species has been observed to breed in large num- 

 bers in the paunch contents of cattle which has been more or less 

 saturated with blood during slaughtering. They do not deposit eggs 

 in this material if no blood is present. 



Under range conditions it has been found that carcasses of large 

 domestic animals are responsible for the vast majority of flies present. 

 During the fall, winter and early spring probably nine-tenths of the 

 flies which breed in carcasses are of this species. Small wild animals 

 and birds also supply favorable breeding places. 



The adults feed freely on various substances but are especially 

 attracted to juices from animal matter. They are rarely observed 

 on fecal matter if no blood or animal tissue is present. Human faeces 

 and excrement of hogs are much more frequently visited than droppings 

 of herbiverous animals. 



In cages ranging up to 10 x 10 x 6 feet, flies were found to require 

 from six to eighteen days after emergence before oviposition began. 

 The adults show a marked tendency to deposit their eggs in large 

 masses. This tendency is more noticeable than in other meat-infest- 

 ing species. Hatching takes place in less than twenty-four hours up 



