19331 
Notes on Hippoboscidae 
103 
Postvertex divided by a slight transverse depression into 
an upper, smooth and shiny area and a lower (frontal) 
portion which is more or less dull. Frons about one and 
one-fifth times as wide as an eye, rarely slightly more. 
Wing 6 to 8 mm. long 0 . coriacea v.d. Wulp. 
The synonymy, characters, distribution and hosts of the 
several species will be fully discussed later. The following 
remarks are preliminary: 
Olfersia sordida Bigot 
According to Mr. J. E. Collin, Bigot’s type is a male and 
shows the characters here given for the species. Originally 
described from Guatemala, 0 . sordida is widely distributed 
in North America. I have seen it from Oregon, Louisiana, 
Florida, the Bahamas, St. Thomas (W. I.), Jamaica, Trini- 
dad, Mexico and Panama. The usual host is the Brown Peli- 
can, Pelecanus occidentalis Linnaeus ; but I have also seen it 
from the Florida Cormorant, Phalacrocorax auritus flori- 
danus (Audubon). 
Olfersia spinifera (Leach) 
I regard Ornithomyia unicolor Walker, Olfersia courtilleri 
“Fairmaire” Courtiller, and Olfersia sulcifrons C. G. Thom- 
son as synonyms of 0 . spinifera . I have seen specimens of 
true spinifera from Florida, Louisiana, the Bahamas, the 
Galapagos, the coast of Brazil, Nihoa Island (near Hawaii), 
and the Solomon Islands. Most specimens came from 
Frigate or Man-o-War birds (species of Fregata) ; but I 
have seen a few taken off Pelicans and Cormorants. 
Olfersia erythropsis Bigot 
This species has been generally confused with O. spini- 
fera. It is identical with Pseudolfersia diomedese Coquillett, 
the types of which I have seen at the U. S. National 
Museum. The type of O. erythropsis, studied by Mr. J. E. 
Collin, has all the characters of diomedese. I have seen the 
species from the Bahamas, Desecheo Island (near Porto 
Rico), the Galapagos, Moorea (one of the Tahiti Group), 
