June, I9i6.] SvVENK : NORTH AMERICAN HiPPOBOSCID-E. 129 



3. Olfersia scutellaris new species. 



Resembling O. albipennis Say, but differing from that species, as above 

 described, in the following characters : Somewhat larger, the length about 

 S mm., the head and thorax alone measuring 3 mm., the thorax being nearly 

 2.5 mm. wide at the widest part, and the distance from the front of the head 

 to the tip of the wing measuring 7.5 mm. ; head less broad, subcircular, the 

 width only one and one sixth times the length, the face very broad, fully two 

 and one half times as broad as the eye ; elevated orbital margins opaque or 

 slightly shiny along extreme outer edges only, their inner edges distinctly 

 hairy ; clypeus four fifths as long as front, the apical section shaped as in 

 O. botaurinorum but with the base slightly wider, so that it is slightly more 

 than one third (three eighths) of the distance between the lateral apices ; 

 antennary processes blackish and bearing much black hair, the palpi slightly 

 shorter than the clypeus ; eyes dull plumbeous ; each side of scutellum with a 

 long black bristle ; wings slightly darker, the first vein joining the costa con- 

 siderably before the first crossvein ; coloration of head and thorax brownish 

 fuscous, the shiny vertex and basal portion of the median longitudinal line 

 stained with reddish, the tips of the tubercles and the scutellum reddish yel- 

 low, the latter contrasting strongly with the much darker mesonotum. 



Type. — Watkins' Station near Manchester, Michigan, on a least 

 bittern (Ixohrychus cxilis). May 30, 1894, by R. H. Wolcott (Coll. 

 No. 190). 



This species is even closer to O. hotaurinorum, just described, 

 than to O. albipennis, agreeing with the former in size, clypeal struc- 

 ture and venation, but easily separated by the more brownish gen- 

 eral coloration, yellowish scutellum, hairy face and mesonotum, 

 broader front, opaque orbital margins and dull-colored eyes. 



4. Olfersia intertropica Walker. 



1849. Ornithomyia intertropica Walker, List of Dipterous Insects in the 

 British Museum, IV, p. 1144. 



1903. Olfersia intertropica Austen, Annals and Magazine of Natural 

 History, Series 7, XII, p. 264. 



The type of this species came from the Galapagos Islands, and 

 Austen records additional specimens from Bahia, Brazil, Orizaba, 

 Mexico and Honolulu, Hawaii. The latter author regards 0. accrta 

 Speiser, described from the Hawaiian Islands, as a synonym of inter- 

 tropica after comparison of paratypes of the former with the cotypes 

 of the latter in the British Museum. A specimen from Orizaba, 

 Mexico, collected in January, 1892, by Prof. Bruner is before me. 

 O. pallidilabris Rondani, described from Mexico, is very close to 

 intertropica, as pointed out by Speiser, but if, as that author indi- 



