ACCIPITER COOPERI, COOPER's HAWK. 335 



Accijnter cooperi. Gray, List B. Br. Mus. 38.— Cass., 111. 1854, 9(5.— Brew., N. A. CiU. 



1857, 20, pi. 5, f. 55 (eog).— Bd., B. N. A. 18.58, 16 ; Mex. B. Snrv. ii, 1859, p-. 



ii, p. 3.— ScL., P. Z. S. 18.59, 389 (critical).— Heerm., P. R. R. Rep. x, 1859, pr. 



vi, 33.— Coop. & Suck., N. H. Wash. Ter. 1860, 145.— Blak., Ibis, iii, 1861, 317.— 



Dre.ss., Ibis, 1865, 323 (Texas). — CoUES, Pr. Phila. Acad. 1868, 43. — AxLEX, 



Bull. M. C. Z. ii, 1871, 321.— Scl. & Sai.v., Exot. Orn. i, 1869, 170.— Lawk., Ann. 



Lye. X. Y. ix. 1868, 134 (Costa Rica).— Coop., B. Cal. i, 1870, 464.— Snow, B. 



Kaus. 1873.— CouES, Key, 1872, 212, fig. 140. 

 Acdpitcr (Coo))era>itur) cooperi, Gray, H. L. i, 1889, 32, No. 312 (" Coo2)erastur," Bp., 1854). 

 Falco ste»/ei/(, AuD., Oru. Biog. i, 186, pi. 36 {Astur) ; ii, 245, pi. 141, 3.— Nutt., Man. i, 



1832, 91. 

 Nisiis cooperi, Ridgw., Pr. Bost. Soc. xvi, 1873, 59.— B. B. & R., N. A. B. iii, 1874, 230. 

 Accipiter jnexjcajnfs, Sw., F. B. A. ii, 1831,45.— Cass., 111. 1854, 96.— Stricic, Orn. Syn. 



185.5, 109.— Bd., B. N. A. 1858, 17.— Coop. & Suck., X. H. Wash. Ter. 1860, 146.— 



CouES, Pr. Phila. Acad. 1866, 43 (Arizona).— Coop., B. Cal, i, 1870, 465,— Stev,, 



U, S. Geol. Surv. Ter. 1870, 462. 

 Accipiter {Cooperastur) mexicamis, Gray, Hand-list, i, 1869, 33, No. 313. 

 Nisus cooperi var. mexicaitiis, Ridgw., Pr. Bost. Soc. xvi, 1873, 59. — B. B. & R., N. A. B. 



iii, 1874, 231. 

 " besldi, Light. ; pileatus, juv. Kacp " {fide Gray), 



b. gundlacM. 



Astur coopo'i, Lejib., Aves Isl. Cuba, 1850, 17. 



Nimoi pileatus, Lemij., Aves Isl. Cuba, 1850 ; Snppl. 



Astur pileatus, Guxdl., J. f. O. 1854, p. — . 



Accipiter guudlaehi, Lawr., Ann. Lye. N. Y. vii, 1860, 2.52. — Gundl., Rep. 224. — Sci., & 



S.VLV., Exot. Orn. i, 170. 

 Accipiter (Cooperastur) gundlachi, Gray, Hand-list, i, 1869, 33, No. 319, 



Hal). — Temperate North America, and southward, Var. gundlachi, Cuba. 



Lieutenant fVarren's Expedition. — 5163, Fort Berthold ; 5164, White Earth River, 

 Dakota ; 5165, mouth of the Yellowstone. 



Later Expeditions.— &)Cyi'i, Uintah Mountains. 



As may be gathered from the above, the habitat assigned to Cooper's Hawk includes 

 that of the so-called Accijnter 7Hexicanus. This last is a pure figment, described by Mr. 

 Swaiuson, who was apparently ignorant of A. cooptri, and perpetuated 'mainly by Mr. 

 Cassin, whose authority has had weight in this instance with all American writers, 

 nul il quite recently. The most that can be claimed for the supposed mexicanus is, that 

 it consists of rather smaller and more heavilj' colored, because more southern, speci- 

 mens, of J. cooperi; but even in extreme cases, the difference is insufficient to warrant 

 retention of the name. Dr, Haydeu's specimens, originally referred to " mexicanus'' 

 by Mr. Cassin, are no smaller than ordinary coope:ri, and not otherwise percejitibly 

 ditferent ; as in too many other cases, the identification, in all j)robability, was made 

 upon some supposed points of geographical distribution that were groundless. So far 

 as I know, the identity of mexicanus with cooperi was first published by ]\Ir. Allen, 

 although others, myself among the number, had previously become convinced of the 

 fact. There is little to add to Mr. Allen's satisfactory exposition of the case. This 

 pretended species disposed of, we have in this country two species of Accipiter, identi- 

 cal in coloration, and nearly so in form, but instantly distinguished by the great dis- 

 parity in size — the difference being relatively as,great as that subsisting between P/cms 

 villosns and F. pubcscus, and the two cases being precisely parallel. The largest females 

 of A./uscus grade up closely toward the small males of cooperi, but there appears to be 

 a constant small gape between them, which, taking sex for sex, is much greater. The 

 fenial(! /uncus is 12 to 14 long, the extent about 26, the wing 7 to 8, the t.vil 6 to 7 ; 

 the male cooperi is 16 to 18 long, about 30 in extent, the wing 9 to 10, tlie tail about 

 8, There is also a difference in the feet, those o{ fuscus being much slenderer, com- 

 paratively as well as absolutely, and relatively longer; the whole foot is not over 3^ 

 long, while that of cooperi is at least 4, generally more. In adult male fuscus the tar- 

 sal scutella tmpiently fuse, leaving a perfectly smooth shank — a state not observed 

 in cooperi. 



Notwithstanding: thft abundance of tlii.s Hawk in the United States, 

 it.s i)erf'('ctly adult pluniajje is rarely noted, and in fact 1 have never seen 

 a description 1 consideit^d entirely satisfactory — that j;ivcn in the 

 " Key " is accurate, but, like most of my accoiuits, necessarily much 

 abbreviated. The adult bird is not only bluish-j?ray on the upper parts, 

 but has a decided shade of the same on the breast and sicU's, A tine 

 male 1 procured at \\'ashinj;ton showed this very plainly; yet it has 

 been supposed specilically distinctive of the Cuban variety. As usually 



