1930 ] 
Notes on Hippoboscidse 
311 
it among the species of Diptera common to Europe and 
America. It is doubtful, however, whether either Lin- 
naeus or Loew actually saw American specimens. Loew’s 
record may have been based upon the earlier statement 
by W. Kirby (1837, Fauna Boreali-Americana, IV, p. 317; 
see Bethune, 1881, Canad. Entom., XIII, p. 169), who 
listed H. equina among the insects of Boreal America, with- 
out, however, mentioning a definite locality. Notwith- 
standing certain discrepancies, Kirby’s description seems 
to have been based upon a specimen of true equina; but 
whether or not it came from North America is open to 
question. In any case, no other entomologist seems to 
have reported this fly from a New World locality, and 
I have never seen an authentic American specimen in any 
collection. Moreover, it is somewhat of a mystery why 
this fly has not become established in America, since it 
must have been brought over repeatedly from the Old 
World. 
Newstead, Dutton and Todd (1907) .state that they 
saw a few examples of H. equina on cattle, shipped at 
Las Palmas, Canary Islands, while on board ship on their 
way to the Belgian Congo. But the two specimens which 
I have seen from Kitobola are the only ones actually taken 
in tropical Africa, where H. equina seems to be replaced 
by H. maculata. Walker (1849, “List Dipt. Brit. Mus.,” 
IV, p, 1140) includes the Cape Colony in the range of the 
species, but no specimens have since been taken in South 
Africa. 
Hosts.- — H. equina is usually found on equines (horses, 
mules and donkeys), sometimes also on cattle and more 
rarely on dogs, rabbits, or camels. Accidentally it may stray 
to birds. Massonat (1909, Ann. Universite Lyon, N. S., 
CXXVIII, p. 242) saw specimens from owls ( Tyto flam - 
mea) and from a kite ( Milvus regalis), and Schuurmans- 
Stekhoven captured one on a pigeon. It is of interest that 
this species has never been taken on the wild equines of 
Africa. 
The predilection which H. equina shows for horses makes 
it very probable that this insect was originally a specific 
parasite of one of the wild horses from which the domestic 
