92 ElDGWAY on the Plumage of Gyrfalcons. 



For a fuller record of Mr. Heushaw's additions, which were first 

 reported in the " American Sportsman," see Rep. Geog. and Geol. 

 Sur. West of 100th Merid., Vol. V, Zoology, Chap. III. 



The following new genera have been proposed for North Ameri- 

 can Birds since 1874 : -;— 



1. Peucedramus, Coues, apud Henshaw, Rep. Geog. and Geol. Expl. 

 W. 100th Merid., V, 1875, 202. Type Sylvia oUvacea, Giraud. 



2. Iridoprocne, Coues. Birds Col. Vail., 1878, 412 (subgenus); Bull. 

 U. S. Geol. and Geogr. Surv., V, Feb., 1879, 74, foot-note (genus). 



3. Amphispiza, Coues. Birds of the Northwest, 1876, 234. — Type, 

 Emherizn biliniala, Cass. 



4. ^chmoptila, Coues. Bull. U. S Geol. and Geogr. Surv. Terr., IV, 

 Feb., 1878, 48 (= Leptoptila, Swain., 1837, not of Lesson, 1831). — Type, 

 yE. jamaicensis (Linn.). jEchnoptila, however. Dr. Coues now decides 

 must give place to Engyptila, Sund. (see below, p. 100). ' 



DESCRIPTION OF THE ADULT PLUMAGE OF HIEROFALCO 

 GYRFALCO OBSOLETUS* 



BY ROBKRT RIDGWAY. 



Having been permitted, through the kindness of Mr. Vennor, to 

 examine the specimens described in " Our Birds of Prey," t under 

 the title of " Falco sacer, Forst.," one of which is the type of " Falco 

 dawsonis," Hall, together with a third example, obtained subsecpient 

 to the publication of the above-named work, these descriptions 

 are presented as being of pi'obable interest from the fact that no 



* Hierofalco gyrfalco obsoletus. 



Falco obsoletus, Gmel., S. N., I, ii, 178S, 268 (based on Plain Falcon, Pen- 

 nant, Arct. Zool., II, 1781, p. 208. 



Falco lahradora, Aud., B. Am., 1831, pi. cxcvi. 



Falco gyrfalco var. labradora, Ridgw., in B. B. & R., Hist. N. Am. B., Ill, 

 1874, 117. 



Falco dawsonis. Hall, Canadian Naturalist and Geologist, VII, 1862, p. 68. 



^^ Falco sacer, Forst.," Vennor, Our Birds of Prey, 1876, 23, pi. iv (nee 

 FoRST. 1772). 



t Our Birds of Prey, or the Eagles, Hawks, and Owls of Canada. By Henry 

 G. Vennor, F. G. S., of the Geological Survey of Canada. With 30 Photo- 

 graphic Illustrations by William Notman. R. Worthington, 750 Broadway, 

 New York. Montreal : Published by Dawson Brothers, 1876. Royal 8vo, 

 pp. i-viii, 1-154, pU. xxx. 



