(ESTRIDJE. 137 



tarandi is parasitic in great numbers in the skin of the rein- 

 deer in both Siberia and boreal America. Four or five species 

 of (Estrus live in the nasal sinuses of sheep, antelope, and 

 horse (Rhincestrus). One species of Cephalomyia lives in the 

 nasal cavities and throat of the camel and buffalo. Six or 

 seven species of Cephenomyia have been found parasitic in 

 the pharyngeal cavities of various Cervids, while various spe- 

 cies of Cutrebra and Rogenhofera have been bred from the 

 skin or scrotum of different rodents, and opossums. Two 

 species of Dermatobia, from the skin of dogs, cattle, cats, 

 deer, and probably apes and man. 



TABLE OF GENERA. 

 IMAGINES. 



1. Mouth-parts very small or rudimentary ; arista bare. ... 2 

 Proboscis geniculate, inserted in a deep slit ; female without extricate 



ovipositor ; first posterior cell narrowed or closed ; arista bare or 

 plumose 5 



2. Face with a median groove 3 



Face with a broad, gently arched shield-shaped surface ; first posterior 



cell narrowed or closed ; tegulas large ; female with elongated ovi- 

 positor; larva? hypodermatic. ....... 6 



3. The fourth longitudinal vein runs straight to the margin of the wing; 



tegulae small; female ovipositor elongate; larva? in stomach and 



intestinal canal GASTKOPHILUS Leach. 



First posterior cell narrowed or closed ; tegula? large ; ovipositor not 

 elongate; larvae in nasal and pharyngeal cavities. ... 4 



4. First posterior cell closed and petiolate ; body nearly bare. 



CESTRUS Linne. 

 First posterior cell narrowly open ; body pilose. CEPHENOMYIA Latreille. 



o. Palpi wanting . HYPODERMA Latreille. 



Palpi present (EDAMAGENA Latreille. 



6. Arista plumose on the upper side. . . ... . . 7 



Arista bare, short and stout; tegulas large; wings without stump at 



angle of fourth vein (Mexico) BOGERIA Austen. 



7. Tarsi broad, flattened CDTEKEBRA Clark. 



Tarsi slender. . . DERMATOBIA Brauer. 



