Vol. XVIll, pp. 161-162 June 29, 1905 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



DESCRIPTION OF A NEW GENUS AND SPECIES OF 



TROCHILIDAE. 



BY HARRY C. OBERHOLSER. 



A single specimen of a hummingbird in the collection of the 

 Field Colnmbian Museum of Chicago seems to represent a new 

 genus as well as a new species. It is here described through the 

 courtesy of Mr. Charles B. Cory, the Curator of Birds in this 

 museum. 



Aeronympha* gen. nov. 



CIi(trs. gtn.— Wings of moderate length, reaching when closed to within 

 about 12 millimeters of the end of the tail ; none of the primaries narrowed, 

 but much as in Vest! pedes and Ci/nnnleshia; tail about two-thirds the length 

 of wing, and forked for one-fourth its own length, the rectrices obtusely 

 and ratlier abruptly pointed, al)out 7 mm. in width, very gradually becom- 

 ing slightly less than this basally ; ni)i>er fourth of tarsus feathered, and 

 togetlier with the lower tibia, enveloped in a small tuft of light-colored 

 feathers, reaching on the former about half-way to the toes ; bill not long, 

 butexceediugthe head,straiglit,subcylindrii'al, moderately slender, slightly 

 dilated laterally near the base, and ratlier abruptly pointed at the tip, 

 neither maxilla nor mandible with any trace of subterminal serrations; 

 nostrils covered by the frontal feathers which extend out on maxilla for 

 nearly one-third tlie length of bill measured from the rictus, and consider- 

 ably beyond tlie feathering between tiie rami of the mandible. 



Type. — Aeronympha prosaniis sp. nov. 



* drip, iiir; vufiipij, nynipli. 



•J7-Pi:oc. Biol. Soc. \V.\.sii., Vol. XYHI, 1905. (ini) 



