36 



PARASITES OF THE DOMESTIC ANIMALS 



after-effect from tfie bites of these Hies tlie.y are a source of niucli tor- 

 ment to live stoclv, not only in Ihe pain produced by their punctures, 

 but in their peculiar buzzidg, which often teri'orizes nervous animals, 

 their frantic and heed- 

 less efforts to escape not 

 infrequentl_y resulting 

 in injury. 



There can be no 

 doubt that the Taba- 

 nidae are concerned in 

 the transmission of cer- 

 tain blood diseases of 

 live stock. It is signif- 

 icant as to their possi- 

 bilities as carriers of 

 anthrax that their at- 

 tack seems to be more 

 commonly d ir e c t e d 

 against cattle than 

 horses. 



Protection. — Little 

 can be done toward 

 repelling the attacks of the flies. Horses at work are protected in a 

 measure by covering them with nets. Where the flies are numerous and 

 especially tormenting it is advisable to remove pasturing animals to a 

 well-shaded retreat during the warmer and sunnier parts of the day. 



Fig. 20. — Tabanus atratus: a 

 (after Osborn, from Riley, Bui 

 mology, Dept. of Agr.). 



lar"\'a: b, pupa; c, adult 

 No. .5, Bureau of Ento- 



Tab.'Lxus Lineola 



Tabanidse (p. 35).— The Green-head Horsefly (Fig. 2f). This is the 

 most wideh' distrijjuted species in North America. It is about five- 

 eighths of an inch in length. Eyes large and bril- 

 liant green, abdomen brown, with a conspicuous 

 grayish line running longitudinallj'' on its dorsal 

 side. It is from this marking that its specific 

 name is derived, while the peculiar coloring of the 

 ej^es gives to it the common name "Green-head." 



The oval, larval, and pupal stages are passed u^eoia "(aftli^ OsbOTu^ 

 in moist places, and in other respects the life cycle from Packard, Bui. No.. 5, 

 is similar to that of Tabanus atratus, though the ^"'t'-'-J,f°{ Entomology, 

 larval period is probablj'' not so long. 



The Green-heads appear in especially large numbers in marsh3^ dis- 

 tricts during the brightest and hottest days of the summer. They 

 attack in greater numbers than the Black Horseflies, and, especially 



