HORSE-FLIES AjSTD WESTERN AGRICULTURE. 



23 



painful part of the feeding process is the puncturing of the skin. 

 The senior author permitted a hungry fly to bite him on the arm. 

 She made several painful punctures before the blood meal was com- 

 pleted. When the beak is withdrawn a little blood usually flows out 

 and coagulates upon the skin. Animals badly bitten have a rather 

 bloody appearance. Unlike T. punctifer, when this species has 

 punctured the skin it is not easily disturbed and can often be cap- 

 tured in the hand. Both males and females in captivity eagerly 

 feed upon sweet substances. They were very fond of mint-flavored 

 candy. Females in captivity could not be induced to bite a host. 

 As discussed on page 31, 

 this species was attracted 

 to and fed upon a fresh 

 beef hide, exposed bloody 

 side out. 



Habits of Males and 

 Mating. . 



Males were rather abun- 

 dant in grass near swampy 

 areas. Several times males 

 were observed to crawl 

 down a grass stem or other 

 object to the surface of 

 water and drink. 



Several matings were ob- 

 served in August, 1919, in 

 a pasture where the grass 

 was about knee high and 

 quite dry. About 8.30 on a 

 warm, bright morning two 

 flies were seen mating in 

 air about 8 feet above the 

 ground. They were flying rapidly and soon came to rest on a stem 

 of grass, where they were captured, still attached. Between 8 

 and 9 o'clock on another day four flies were observed in the air 

 apparently all clinging together. After about 10 seconds they 

 separated and flew away. A few minutes later two were seen in the 

 air, but they soon separated and disappeared. Another pair mating 

 in the air came to rest on a stem of grass, remained for a minute and 

 a half, then separated and flew away. One pair mating in air were 

 interrupted by two other flies, apparently of the same species. None 

 of these were captured. Observations did not reveal whether mating 

 began in flight or at rest. 



Oviposition. 



Egg masses were very hard to find in nature. After a long search 

 a few masses were finally found on stems of grass or on dried stems 

 from 2 to 4 inches above the ground in marshy places. In cages the 

 egg masses were found on straws and on the under side of sheets of 

 cork an inch or two above and overhanging the water. 



Fig. 15. — Tabanus jihuenops feeding on a horse. 



