340 FALCO MEXICANUS VAR. POLYAGRUS. 



List of specimens. 



Lieutenant Warren's Expedition.— 51G7, Fort Randall, Dakota ; 5168-69, Knife River, 

 Missouri. 



Later Expeditions. — 60333, Laramie Peak ; 60334, Camp Carling, Wyoming ; 60616, 

 Uintah Mountains; 61094, Sulphur Springs. 



The specific identity of Mr. Cassin's Falco poh/agrus with the little known F. mexicanus 

 of Prof. Lichtenstein may be considered established. The discrepancies noted in my 

 article, above cited, are in part at least due to age, sex, or other fortuitous circum- 

 stances. There may be, however, as Mr. Ridgway has jirobably shown, certain differ- 

 ences due to climatic influences which may warrant recognition of two varieties. But 

 I am not at present prepared to follow Mr. Ridgway in referring tbese forms to the old 

 world F. laniarius, although they are unquestionably very closely related. As Mr. 

 Cassin pointed out, the resem1)lance is also very great to the Indian Jugger — F. jufjger, 

 Gray, 111. Ind. Zool. ii, pi. 26 ; Jerd., 111. Ind. Orn. pi. 44 ; in fact, the specimens I have 

 examined, excepting some very old ones, come nearer the representations I have seen 

 of F. jugger than of laniarius proper. This form, jugger, is also referred by Mr. Ridgway 

 to laniarius as a variety, but, until its varietal relationship is established, it may be 

 best to keej) the two apart, and also to recognize the American form as specifically 

 distinct. 



The comparatively late discovery of this bird as an inhabitant of the 

 United States is particularly interesting, not only as giving- us a hitherto 

 unknown representative of the familiar Lanier group of Falcons of the 

 Old World, bat also as adding another to the numerous instances of close 

 alliance of Western American birds to certain Old World forms. 



This interesting bird is of general distribution in open country 

 throughout the West, and rather common. It appears to be essentially 

 a prairie species, a circnmstance probably explaining its occurrence in 

 Illinois, where it was noted by Mr. J. I). Sargent and Mr. 11. Ridgway. 

 Prof. Snow catalogues it as rare in winter in Kansas. Dr. Hayden re- 

 marks that it is found at various points along the Missouri and on the 

 Platte, though not abundantly. Several observers found it in New 

 Mexico and Arizona. On the Pacific coast it is known to occur at 

 various points, from Fort Dalles, Oregon, where it was procured by Dr. 

 Suckley, to Monterey, whence came one of the types of the species, it 

 appears to be particularly abundant in the open portions of Southern 

 California, where Dr. Cooper told me he often saw it, in company with 

 the Ferruginous Buzzard, resting on the ground or flying low over the 

 surface in the neighborhood of the villages of the California ground 

 squirrel {Spermophilus heechei/i), for which animals it was doubtless on 

 the watch. The only time I ever saw it alive was in this region. While 

 at Drumm Barracks, one of these birds dashed past, returned in an in- 

 stant, and alighted on the roof of the house, while Dr. Cooper and I 

 were standing on the jiorch. It had evident designs upon the Black- 

 birds, thousands of which were scurrying about. Watching the bird 

 for a few moments, and perceiving it had no intention of leaving at that 

 particular time, I went into the house for my gun, and loaded for its 

 especial benefit. The bird watched the whole proceedings, eyeing me 

 audaciously, and never stirred from its perch until 1 made an irresistible 

 appeal. I found it to be a young bird, the iris brown, the feet dull 

 bluish, the claws black, the bill bluish-black, with the base of the under 

 mandible yellow. 



This Falcon is inferior to none of our country in strength and spirit, 

 unless it be that the (iyrfalcon surpasses it in this respect. It even 

 attacks and overpowers the great hares of the West {L. eallotis and al- 

 lies) — animals actually larger and heavier than itself. With its nidifi- 

 cation I am unacquainted ; I have, however, examined its eggs, of which 



