VOL. XVIII, PP. 161-162 JUNE 29, 1905 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



DESCRIPTION OF A NEW GENUS AND SPECIES OF 

 TPvOCHILIDAE. 



BY HARRY C. OBERHOLSER. 



A single specimen of a hummingbird in the collection of the 

 Field Columbian 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. 



Chars, gen. 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 Cynnolrsbia ; tail about two-thirds the length 

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

 and rather abruptly pointed, about 7 mm. in width, very gradually becom 

 ing slightly less than this basal ly ; upper fourth of tarsus feathered, and 

 together 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, 

 but exceeding the head, straight, subcylindrical, moderately slender, slightly 

 dilated laterally near the base, and rather 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 the length of bill measured from the rictus, and consider 

 ably beyond the feathering between the rami of the mandible. 



Type. Aeronympha prosantis sp. nov. 



* o-^p, air ; VII/M^IJ, nymph. 



27-Puoc. BIOL. Sue. WASH., VOL. XVIII, 1905. (1C1) 



