17 I BIRDS OK ILLINOIS. 



Buteo swainsoni Boiiiip. 



SWAINSONS HAWK. 



Fopnlar synonym. Hiowii Hawk. 



JliilfO rulgariis Sw. A Uicil. F, l!.-.\. ii. Isil.Jl, |>l LTdimloaJ.).— AUD.B. Am. I.KM'l.pl.C 



ISutru .tiraiimoiii Up. Coiiiii. lAM, l>ctS.3.— Cii.is. in KiilnlV 11. N. Am. 1M8. 11»: cil. INCH. pi. 



lH(f('muliMUl.l.-Ii.vlliD, Cat. N. Am. B. Kid, No. I8.-C0UE8. Key. 1X72. 217: Clun-k 



List. 1874, No. 3M: il i-d. isxi. No. .Wf; B. N. W. 11*74. 355.— B. B. & R. Hist. N. Am. 



B. iii, 1874. asi.— RiiHiw. Nom. N. Am. B. 18X1. No. 44i 

 Hiileo viotilaniis NuTT. Man. ml. 1K40, i, 112. 

 Zlioteo hainlii HoY. Pnn-. Plill. Acad. 1K53, 4,M (= youne).— Ca88. IlluBtr. 1855, pl. 41: in 



Bairil's B. N. Am. 1858. 21.-Baibd, Cat. N. Am. B. 1859, No. 19. 

 lliitco insio'iatus Cass. liliistr. 18,''>4, 1(12. 198. pi. 41 (= melunistic pbusu); inBiUrd"s B.N. 



Am. 1858, »;).— Baibk, Cat, N. Am. B. 185'.". No. 21. 

 Jitilfo oxypli-i-Hn Cabs. Proc. Pliil. Acad, vii, 1855, 282 (= youue): in Baird's B. N. Am. 



1858, »li: ib. od. 186(1, pl. 15, lie. 2.— Baird. Cat. N. Am. B. 1859, No. 28.-COUK8. Key. 



18?2, 218. 

 ISiiteo .iiraiiisiiiii var. oxUDlenis B. B. & R. Hint. N. Aiii. B. iii. 1874. Wi. 



Had. Western North America, nortli to the Yukon and McKenzie River districts, 

 south to Central .\m<'riea (Gtnitcmala and Costa Rica), east to tlie Mississippi Valley 

 (Illinois, Wisconsin, Arkansas, etc.): occasional visitant further eastward, especially 

 north of the Great Lakes and St. Lawrence. Massachusetts (Brewster). SlraKKllntr (V) 

 over South America, as far as PatiiRonia. ArRcntine Republic, and Masafuera. 



8p. Char. Only throe outer primaries with inner webs emarcinated; third or fourth 

 (usually the third) QUill longest; first shorter than the sixth (usually about eqinil to— 

 rarely shorter than— the seventh). Wine reaching nearly to the end of the tail: prima- 

 ries exceediUB secondaries by about one third the lenBlh of the wine. Tail even. Trans- 

 verse seutelln' on front of the tarsus. 9-13. Color: tail erayish brown, or crayish, some- 

 times with a hoary cast, usually passing narrowly into whitish at the tip, and crossed by 

 an indefinite number of very indistinct narrow bands of a darker shade. Colors of other 

 portions extremely variable. Adult. Nearly uniform dusky brown above, the frontlet, 

 concealed bases of occipital feathers, and the upper tnil-coverts more or less mixed with 

 white; beneath sometimes pure white, with a broad patch of uniform brown or rufous 

 on the breast, and white throat-patch, but from this liRht extreme the lower parts vary 

 to uniform dusky chocolate or sooty brown, throueh Intermediate shades of ochraeeous 

 or rufous upon which ground deeper colored bars arc visilili' on portions posti'rior to 

 the pectoral patch ; very rarely the lower parts are irregularly spotted with brown, while 

 the pectoral patch is broken up into similar spotting by the admixture of more or less 

 of white. In the extreme melanislic condition the bird is uniformly blackish hrown, 

 with white bars on the crissum. Vouno- Ochraeeous and purplish black, in relative 

 quantities varying according to the individiuil: the oehraeeous forms the ground color, 

 and usually predominati's, but is sometimes much less in amount than the black; tho 

 tail is the same as in the adult. 



n. Normal phase. 

 Atlvlt. Above continuous blackish brown, the feathers nsinilly with somewhat paler 

 borders; outer scnpuhirs and upjicr tail-coverts very rarely tinged with rufou.s— the latter 

 usually more or less barred with white or ashy; occipital feathers white beneath the sur- 

 face ; primaries plain brownish black, without trace of bars on outer webs. Throat and chin 

 more or less white, ustnilly inform of a sharply defini'd patch: jugnlnm and breast brown, 

 generally plain, very rarely spotted with whitish, the tint varying from rufous imalcl 

 tothccolor of Ihi! upper parts (femali>). Other lower parts varying from white to ochra- 

 eeous (rarely almost rufous), generally more or less barred, or spotted transversely, with 



