BUTEO SWAINSONI. 587 



and tlicii tlioy would raise their wings and liop briskly in pnr.snit of some 

 objectj which; at the distance, we coald not distinguish. Cautiously ap- 

 proaching them, four were shot dni-ing the forenoon; they would not allow 

 us to walk to within gunshot, but after flying for a few minutes would 

 sometimes return toward us, and, passing by, give us a fair opportunity for 

 Aving-shots. Upon dissection, the stomachs of these specimens were fjund 

 to be filled entirely with the large crickets mentioned above. 



At our camp in Parley Park we reared four young birds of this species, 

 which were taken from tlieir nests while in the downy state. As they grew 

 up under our care they became very pleasing pets, being exceedingly docile, 

 and much attached to those who fed them. AVhen sufficiently old to use 

 their wings they showed no disposition to leave, although they were 

 allowed full liberty all the while; and though they made frecjuent tours of 

 inspection over the neighboring meadows, and occasional foraging excur- 

 sions among the flocks of Blackbirds {Scolecopliagiis cijanocepliuhis) Avhich 

 frequented the vicinity, they seldom went far away, and always returned 

 after a short absence. They were fed principally upon bits of fresli beef 

 and mutton, varied occasionally by the carcasses of birds we had skinned. 

 Their chief amusement about camp consisted in chasing grasshojipers over 

 the ground, wliich they pursued by leaping after them, with the wings 

 extended; but when not engaged in this occupation they usually [jerched 

 quietly upon the fence near by or u[)on the tents. 



List of siH-cimens. 



109, 9 juv ; Big Bend of the Tnickee (Camp 12), Nev.ada, Jiil'y 20, 1867. IG.J— 

 45_13_10J— 1— ]|— 6i— 3. Bill, dull black, inclining to pale blue on the rictus and 

 on the basal half of the lower mandible; cere, pale yellowish green; iris, cinereous, 

 with a brownish outer wash; tarsi and toes, very pale ashygrecn. 



113, 9 a<l. {fuliginous plumage, parent of Nos. 109, 115, UG, and 117); Canii) 12, 

 July 29, lS(i7. 21J— 53— 17— M— 1— 2— S§— 5. Weight, 2^ pounds. Bill, slate-black, 

 light blue basally; cere and rictus, pure light yellow; iris, deep hazel; tarsi and toes, 

 light chrome-yellow; claws, black. 



114, cj ad. {normal plumage, mate of the preceding); Camp 12, July 29, 1807. 

 193_48— 10— 125— 1|— If— 75— 4J. Weight, IJ pounds. Cere and rictus, light dull 

 lenion-vellow; tarsi and toe.s, deep chrome-yellow; iris, deep hazel. 



115, 9 juv.; Gamp 12, July 29, 1807. 19;s-17— U-ll— i;?— l;'— 7A— 33. 

 Weight, 2 pounds. Same remarks as to No. 109. 



