Part 75

[14] _Strix flammea_, var. _guatemalæ_, RIDGWAY. Central American specimens differ very appreciably from Mexican and North American examples, in being considerably darker-colored in the extreme phases of plumage. Eight of eleven specimens convey an impression of decided difference in this respect at a mere casual glance. The extremes of plumage in this series are as follows:—Darkest (No. 40,961, Chimandega, Nicaragua; F. Hicks): The dusky mottling of the upper parts is altogether darker than in any example from Mexico or northward, and prevails, with great uniformity, over the entire surface; the white specks are linear, instead of roundish. On the primaries and tail, the blackish and ochraceous are about equal in extent, the latter color forming five bands on the quills, and four on the tail. The facial circle is bright dark orange above the ears, and the portion below the ears continuous black; the face is reddish-white, strongly tinged with wine-brown, while the spot in front of the eye is deep black. The whole lower parts are deep orange-ochraceous, with numerous irregular specks of dusky, which posteriorly become broken or confused into ragged zigzag transverse mottlings, while on the lower tail-coverts they form irregular transverse bars. Wing-formula, 2, 1–3. Wing, 13.00; tail, 5.90; culmen, .85; tarsus, 2.90; middle toe, 1.50. Lightest (No. 41,252, ♂, San José, Costa Rica, Aug. 23, 1865; José C. Zeledon): The dark tint above, though prevalent, is a continuous wash of grayish, instead of a fine mottling of blackish and white; the white specks are nearly obsolete. The wings are superficially plain grayish, this overlaying the ground-color of ochraceous-orange; and have visible spots only on the primaries, near their shafts. The tail has four rather distinct grayish bands. The facial circle is ochraceous, somewhat darker across the foreneck; the face white, with the ante-orbital spot claret-brown. Entire lower parts immaculate pure white. Wing-formula, 2, 1=3. Wing, 12.30; tail, 5.30; culmen, .70; tarsus, 2.75; middle toe, 1.45.

No. 24,283, Nicaragua, (Captain J. M. Dow,) is like the specimen just described, in the uniform dark wash of the upper parts, but this is deeper; the lower parts, however, are quite different, being ochraceous-orange, instead of pure white.

The remaining five specimens (from San Salvador, Costa Rica, and Nicaragua) are alike, and differ from northern birds in the deeper dark mottling of the upper parts; the white specks very conspicuous, and usually sagittate. The facial circle deep black where it crosses the foreneck. The lower parts vary in color from nearly pure white to deep orange-rufous; the dark markings of the lower surface are larger, more angular, and more transverse than in true _pratincola_. The wing measures 11.30–13.00; tarsus, 2.55–2.95. The northern form varies from 12.50–13.00 (wing) and 2.50–2.85 (tarsus). It is thus seen that while these southern birds average smaller in general dimensions, they have actually larger feet, the average length of the tarsus being 2.80 in the Central American series, and only 2.60 in the northern series. This exactly coincides with the case of _Sturnella_, the _S. magna_ var. _mexicana_ of the same region being smaller bodied and shorter winged than var. _magna_ of the United States, but with much larger feet, see p.

[15] _Strix flammea_, var. _perlata_. _Strix perlata_, LICHT. Verz. Doubl. 59, 1823.—TSCHUDI, Av. Consp. Wiegm. Archiv. 267, 1844.—HARTT. Syst. Ind. Azara. p. 3.—MAX. Beitr. III, 263 (excl. syn.).—STRICKL. Orn. Syn. I, 1855, 180 (excl. syn.). _Strix flammea_, DARWIN, Zool. Beag. 34.—SCHOMB. Verz. Faun. Brit. Guian. p. 732.—SPIX, Av. Bras. I, 21.

This is a still further differentiated or more appreciably modified race. It differs in smaller size (wing, 11.70–12.50; tail, 4.80–5.20; tarsus, 2.40–2.75) and more square tail, while the colors also present constant differences. The tail is much lighter compared with the wings, the bands narrower and more sharply defined, though the same in number.

[16] _Strix flammea_, var. _furcata_. _Strix furcata_, TEMM. Pl. Col. 432, 1838.—D’ORB. Hist. Nat. Cuba Ois. p. 34. _Hab._ West Indies (Cuba and Jamaica).

This form is the most distinctly characterized of all the races of _S. flammea_ which we have examined. It has the general plumage decidedly lighter and less rufous, while the secondaries and tail are abruptly lighter than the adjacent parts, and usually free from bands, though there are sometimes traces of them.

All the American races of _Strix flammea_ differ very decidedly from the European form (var. _flammea_) in much larger size. The differences in color are not so appreciable, and there is hardly any certain difference in this respect. The extreme phases, however, appear to be darker in the var. _flammea_ than in the var. _pratincola_. The supposed differences in the character of the feathers fringing the operculum, insisted on by MacGillivray (History of British Birds, III, 1840, p. 473), I am unable to appreciate, for I cannot find that they differ in the least in the two races. That excellent ornithologist states that in the American “species” the feathers of the operculum are reduced to a simple tube, having neither filaments nor shaft, while in the European bird they are perfect feathers, with all their parts complete. Though this may have been the case with the one or more specimens of _pratincola_ examined by Mr. MacGillivray, I have yet to see an American specimen which has not the feathers of the operculum just as perfectly developed as in European examples.

[17] _Strix flammea_, var. _delicatula_. _Strix delicatula_, GOULD, P. Z. S. 1836, 140.—IB. B. Australia, I, pl. xxxi.—STRICKL. Orn. Syn. 1855, 180. _Hab._ Australia.

[18] _Strix flammea_, var. _javanica_. _Strix javanica_, GMEL. S. N. I, 295, 1789.—LATH. Ind. Orn. p. 64, and Gen. Hist. I, 357.—HORSF. L. Trans. XIII, 139.—GRAY, Gen. B. fol. sp. 5, pl. xv.—SYKES, P. Comm. Zoöl. Soc. pl. ii, 81.—STRICKL. Orn. Syn. I, 1855, 180. _Phodilus javanicus_, BLYTH, Journ. As. Soc. Beng. XIX, 513. _Strix flammea_, PEARS. & BLYTH. _Hab._ Java and Southern India, and Eastern Africa.

[19] _Otus vulgaris._ _Strix otus_, LINN. S. N. p. 132, 1766.—_Asio otus_, LESS. STRICKL.—_Bubo otus_, SAVIGN. _Ulula otus_, MACGILL. _Otus vulgaris_, FLEM. Brit. An. p. 56, 1828, et AUCT. _O. europæus_, STEPH. 1. _O. albicollis_, DAUD. _O. italicus_, DAUD. _O. communis_, LESS. _O. aurita_, MONT. _O. asio_, LEACH. _O. sylvestris_, _O. arboreus_, and _O. gracilis_, BREHM.

[20] _Otus stygius._ _Nyctalops stygius_, WAGL. Isis, 1832, p. 1221.—GRAY, Gen. B. p. 6, ed. 2, p. 8.—BONAP. Consp. Av. p. 50. _Otus stygius_, PUCH. Rev. Zoöl. 1849, 29.—GRAY, Gen. B. fol. sp. 12.—KAUP, Monog. Strig. Cont. Orn. 1852, p. 113. _Asio styg._ _? Otus siguapa_, D’ORB. Hist. Nat. Cuba Ois. p. 31, Tab. 2, 1840.—GRAY, Gen. fol. sp. 9.—BONAP. Consp. 50 (Cuba). _Otus communis_, var., LESS. Tr. Orn. p. 110. _Hab._ South America (Brazil, ? Cuba, St. Paulo, KAUP).

[21] _Syrnium nebulosum_, var. _sartorii_, RIDGWAY (Mexican Barred Owl). _Hab._ Mirador, Mexico. CHAR. _Adult_ (♀, 43,131, Mirador, near Vera Cruz, Mexico, “pine region”; Dr. C. Sartorius). In general appearance like _nebulosum_, but the brown very much darker, and less reddish,—that of the markings below very nearly black; the pattern, however, precisely the same, and there is about the same proportion between the light and the dark bars as is seen in the average of _nebulosum_. The face is plain dirty white without the brown bars or semicircles,—a constant and conspicuous feature in _nebulosum_. There is the same number of spots on the primaries, and of bands on the tail, as in _nebulosum_. The white beneath is without any ochraceous tinge; the primary coverts are plain dark brown. Wing-formula: 4–3=5; 1 intermediate between 8 and 9. Wing, 14.80; tail, 9.00; culmen, 1.05; tarsus, 2.20; middle toe, 1.60. This race of the _S. nebulosum_ presents very appreciable differences from the bird of the United States. As stated above, the brown is much darker and less reddish, while the face is wholly destitute of the concentric dusky rings seen in _nebulosum_ proper. To Dr. Charles Sartorius, who, by the presentation to the Smithsonian Institution of numerous elegantly prepared specimens, has added so much to our knowledge of the birds of the vicinity of Mirador, I take great pleasure in dedicating this new form.

[22] _Syrnium nebulosum_, var. _fulvescens_. _Syrnium fulvescens_, SALVIN, P. Z. S. 1868, 58. CHAR. General appearance of var. _nebulosum_, but smaller and much more ochraceous. Ground-color of the plumage ochraceous, inclining to a deep fulvous tint on the upper parts, but paler below. Feathers of the upper surface tipped with dark umber-brown, and sometimes with an additional bar about the middle of the feather. The fulvous bars much exposed, so as to exceed the brown in amount. Face grayish-white, tinged outwardly with ochraceous. Beneath with the markings of _nebulosum_ on a deep and uniform ochraceous ground. Wing, 12.75; tail, 8.50; culmen, .95; tarsus, 2.45; middle toe, 1.20 (Coll. Bost. Soc., No. 367, Guatemala; Van Patten).

[23] _Nyctale tengmalmi_, var. _tengmalmi_. _Strix tengmalmi_, GMEL. S. N. p. 291, 1789 (et AUCT. var.). _Nyctale t._, BONAP. et AUCT. _Noctua t._, CUV. et AUCT. _Athene t._, BOIE. _Ulula t._, BONAP. et AUCT. _Scotophilus t._, SWAINS. _Strix dasypus_, BECHST. (1791) et AUCT. _Nyctale d._, GRAY. _Strix passerina_, A. MEYER, 1794.—PALLAS. _Nyctale planiceps_, BREHM, 1831. _N. pinetorum_, BREHM, 1831. _N. abietum_, BREHM, 1831. _N. funerea_, BONAP. 1842 (not of LINN., 1761, which is _Surnia ulula_). “_N. kirtlandi_,” ELLIOT, Ibis, II, Jan., 1872, p. 48 (not of HOY!).

[24] _Nyctale harrisi_, CASSIN, Pr. Ac. Nat. Sc. Philad. IV, p. 157, Feb., 1849.—IB. Tr. A. N. S. II, 2d series, Nov., 1850, pl. v.

[25] _Scops asio_, var. _enano_, LAWRENCE, MSS. This well-marked race is founded upon two specimens,—one from Mexico, in the cabinet of Mr. Lawrence, and another from Guatemala, in the collection of the Boston Society of Natural History. They are exactly similar in colors; but, as might be expected, the more southern specimen is the smaller of the two. This form very closely resembles the _S. atricapilla_ (NATT.) STEPH. (Temm. Pl. Col. 145), but may be readily distinguished by the haired toes, they being perfectly naked in _atricapilla_. The latter species is found as far northward as Mirador.

[26] _Scops semitorques_, SCHLEGEL, Fauna Japonica, t. 8. For the privilege of comparing specimens of this bird with _S. kennicotti_, I am indebted to the courtesy of the officers of the New York Museum, who kindly sent the fine specimens of that museum for examination.

[27] _Bubo virginianus_, var. _magellanicus_. _Strix_ (δ) _bubo magellanicus_, GMEL. Syst. Nat. 1789, p. 286.—DAUD. Tr. Orn. II, 210.—LESS. Voy. Coq. I, 617; Isis, 1833, 76. _Asio mag._ LESS. Man. Orn. I. p. 116, 1828. _Bubo mag._ GRAY, List Birds Brit. Mus. 1844, p. 46. _Strix nacuruta_, VIEILL. Nouv. Dict. Hist. Nat. VII, 44, 1816; Enc. Méth. III, 1281, 1823. _Strix crassirostris_, VIEILL. Nouv. Dict. Hist. Nat. VII, 44 (1817); Enc. Méth. III, 1280. _Otus crass._ GRAY, Gen. B. fol. sp. 6 (1844); List Birds Brit. Mus. p. 106. _Bubo crass._ BONAP. Consp. Av. p. 48 (1850).—KAUP, Monog. Strig. Cont. Orn. 1852, 116 (under _B. virginianus_). _Asio crass._ STRICKL. Orn. Syn. I, 208, 1855. _Strix macrorhyncha_, TEMM. Pl. Col. 62, 1820. _Otus ? macr._ STEPH. Zoöl. XIII, pt. ii, p. 59. _Otus macr._ CUV. Règ. An. (ed. 2), I, 341.—LESS. Tr. Orn. p. 109. _Asio macr._ LESS. Man. Orn. I, 117.

[28] _Bubo mexicanus_ (GMEL.) RIDGW. _Asio mexicanus_, BRISS. Orn. I, 498, 1760.—STRICKL. Orn. Syn. I, 208, 1855 (excl. syn.). _Strix mexicana_, GMEL. S. N. p. 288, 1789.—LATH. Ind. Orn. p. 54; Syn. I, 123; Gen. Hist. I, 314, A.—DAUD. Tr. Orn. II, 214.—SHAW, Zoöl. VII, 228.—_Otus mexicanus_, STEPH. Zoöl. XIII, pt. ii, p. 57.—_Bubo clamator_, VIEILL. Ois. Am. Sept. pl. xx, 1807. _Scops cl._ GRAY, List Birds Brit. Mus. 1844, p. 45. _Strix clamata_, VIEILL. Enc. Méth. III, 1279, 1823. _Strix longirostris_, SPIX, Av. Bras. pl. 9 _a_, 1824. _Strix maculata_, MAX. Beitr. III, 281, 1830. HAB. Middle and South America generally. A very distinct species, and a typical _Bubo_, although usually referred to the genus _Otus_.

[29] _Nyctea scandiaca_, var. _nivea_ (see p. 000). _Strix scandiaca_, LINN. S. N. (12th ed.) I, 132 (1766). _Nyctea scandiaca_, YAWELL, Hist. Brit. B. 1872, 187. _Strix nyctea_, LINN. S. N. I, 1766, 132. _Strix nivea_, DAUD. Tr. Orn. II, 1800. _Nyctea nivea_, GRAY, Gen. fol. sp. 1, pl. xii, f. 2.

[30] No. 559, collection of R. Ridgway (♂, Mt. Carmel, Wabash County, Southern Illinois, October 14, 1869). 22½–54. Weight, 3½ lbs.; bill black; iris gamboge-yellow; toes ashy; claws horn-color, black at ends.

[31] _Surnia ulula_, var. _ulula_. _Strix ulula_, LINN. S. N. I, 1766, 133. _Surnia ulula_, BONAP. Cat. 1838, 22.

[32] _Glaucidium passerinum_, var. _passerinum_. _Strix passerina_, LINN. I, 133, 1766. _Glaucidium passerinum_, BOIE, Isis, 1826, 976.—SHARPE & DRESSER, Birds Europe, II, April, 1871. _Surnia passerina_, KEYS. & BLAS. Wirb. Europ. 32, 1840. _Microptynx passerina_, KAUP, Contr. Orn. 1852, 107. _Noctua passerina_, SCHLEG. Mus. Pays-Bas. _Striges_, p. 41, 1862. _Strix pusilla_, DAUD. Tr. Orn. II, 205, 1800. _Strix pygmæa_, BECHST. Nat. Deutschl. IV, 978, t. xxiv, 1805. _Strix acadica_, TEMM. Man. d’Orn. I, p. 96, 1820 (_nec_ GMEL.).

[33] _Glaucidium infuscatum_, var. _infuscatum_. _Strix infuscata_, TEMM. Ind. Général, 1821. _Athene i._, BONAP. Consp. 37, 1850 (excl. syn.). _Glaucidium i._, KAUP, Cont. Orn. 1852, 103. ? _Strix eluta_, ILLIG. in Mus. Berl. Cab. Azar. No. 49. _Strix passerinoides_, TEMM. Pl. Col. 344. _Surnia p._, BONAP. Os. Cuv. Règ. An. I, 57. _Noctua p._, LESS. Man. & Tr. Orn.

[34] _Glaucidium infuscatum_, var. _gnoma_. _Glaucidium gnoma_, WAGL. Isis, 1832, 275.—KAUP, Monog. _Strigidæ_, in Contr. to Orn. 1852, 103 (under _G. infuscatum_).—STRICKL. Orn. Syn. I, 163, 1855 (under _G. infuscatum_). _Athene gnoma_, GRAY, Gen. Birds, fol. sp. 35, 1844. _Hab._ Whole of Middle America, from Panama northward to the Rio Grande and Mazatlan. Probably yet to be found in Texas or New Mexico.

[35] Gray, in his “Hand List,” gives in addition _S. fusca_, VIEILL., a West Indian (“Antilles”) species, which proves to be not congeneric with _S. cunicularia_, and also _S. domingensis_ (GM.) MÜLL., which I cannot identify as one of the races of _S. cunicularia_.

[36] _Speotyto cunicularia_, var. _grallaria?_ _? Strix grallaria_, SPIX, Av. Braz. I, 21, 1824.—? TEM. Pl. Col. 146. I am by no means satisfied that this form is the true _grallaria_, but it seems to come nearer to it than any other described. Three specimens (two from Peru, in the National Museum, and one, without label, in the Museum of the Boston Society of Natural History) have been examined, and agree in the characters diagnosed above.

[37] _Speotyto cunicularia_, var. _cunicularia_. _Strix cunicularia_, MOLINA, St. Chil. 1782, 343. GMEL. S. N. 292, sp. 28,—and of other authors referring to the South American bird.

[38] _Speotyto cunicularia_, var. _guadeloupensis_, RIDGWAY. This bird is merely a very dark local form of the common species, though it differs very appreciably in the sharper definition, greater extent, and more intense tint of the brown markings of its plumage.

I have been unable to find any description of this form, and believe it to be unnamed. It is certainly not the _S. dominicensis_, GMEL. (S. N. 296, _S. domingensis_, MÜLL. GRAY’S Hand List, 43, No. 438), not _S. fusca_, VIEILL. (GRAY’S Hand List, No. 439). The type is in the collection of the Boston Society of Natural History, and belongs to the Lafresnaye collection (No. 787).

[39] We give, above, three well-marked illustrations of asymmetry: two relating to the auditory apparatus of the two sides of the head, and one of opposite sides of the skull.

[40] As in the case of the _Strigidæ_, my determinations of the North American species of _Falconidæ_ were furnished, according to request, to Dr. Coues, for use in his “Key to North American Birds.” (R. R.)

[41] By this is meant that they are all of equal length and thickness, and not progressively smaller from the posterior one to the outer, as in all _Falconidæ_ with the sole exception of _Pandion_, though there is a very near approach to this feature in one or two of the species of _Haliætus_.

[42] As in all the _Strigidæ_.

[43] Embracing besides the _Falcones_ all the Polyborine genera, besides _Herpetotheres_ and _Micrastur_.

[44] As in the Polyborine forms of the _Falconinæ_.

[45] Extremes of sixty specimens.

[46] Sometimes there are more or less distinct linear streaks on the head and neck, or on the pectoral region.

[47] Sometimes the irregular markings above have a transverse tendency.

[48] _Falco gyrfalco_, var. _gyrfalco_ (LINN.). _Falco gyrfalco_, LINN. S. N. 1766, p. 130.—GMEL. S. N. 275.—SCHLEG. Rev. Crit. II, Tr. de Fauc. pl. iii; F. van Nederl. Vog. pls. iii and iv.—NAUM. Vog. pl. cccxci. _Hierofalco gyrfalco_, SCHLEG. BONAP. Rev. Zool. 1854, 535.—NEWTON, Oötheca Wolleyana, I, 87, pl. c. _F. gyrfalco norvegicus_, WOLLEY. _Falco gyrfalco norwegicus_, SCHLEG. Mus. Pays-Bas, 1862, 12. _Falco candicans_, var. γ, BLAS.

Wing, 13.00–14.50; tail, 9.30; culmen, .98; tarsus, 2.50; middle toe, 1.92.

[49] _Falco lanarius_, var. _lanarius_ (SCHLEGEL). _Falco lanarius_, SCHLEG. Krit. Ueb. II, et 11.—IB. Tr. Fauc. 6; Mus. Pays-Bas, _Falcones_ 14; Abh. Zool. 16; Rev. 1844, 2; Naum. 1855, 252; Ibis, 1859, 86.—BREE, B. Eur. I, 1859, 37 (plate of adult!).—TRISTRAM, Ibis, 284.—GRAY, Hand List, I, 1869, 19, No. 171. PELZ. Ueb. der Geier und Falk. II, 1863, 20. _Falco lanarius_ α, SCHLEG. Tr. Fauc. 23. _Gennaia lanarius_, SCHLEG.—BONAP. Rev. 1854, 535. _Falco feldeggii_, SCHLEG. Abh. Zool. 3–6.

[50] _Falco lanarius_, var. _mexicanus_ (LICHT.). _Falco mexicanus_, “LICHT. Mus. Berol.”—SCHLEG. Abh. Zool. 1841, 15.—SCHLEG. _Falcones_, Mus. Pays-Bas, 1862, 18.—PELZ. Neb. der Geier und Falk. II, 1863, 19. “_Falco sublanarius_, NATTERER.”—PELZ. Ueb. der Geier und Falk. II, 1863, 19.

[51] _Falco lanarius_, var. _jugger_ (GRAY). _Falco jugger_, GRAY, Hardw. Ill. Ind. Zool. II, pl. xxvi, 1832.—BONAP. Consp. 24.—GOULD, B. Asia, pl. i.—JERDON, B. India, 30.—STRICKL. Orn. Syn. 1855, 79, No. 129.—SCHLEG. Abh. pl. xv; Mus. Pays-Bas. I, 17. _Falco lugger_, JERD. Aladr. Journ. X, p. 80; Ill. Ind. Orn. pl. xliv.—BLYTH, Journ. Ass. Soc. Bengal, XI, 104. _Falco thermophilus_, HODGS. Zool. Misc. 1844, 81. _Falco lanarius?_ BLYTH, J. As. Soc. Beng. XIX, 318.

[52] Extremes of more than one hundred specimens measured!

[53] _Falco communis_, var. _orientalis_ (GMELIN). _Falco orientalis_, GMEL. S. N. 1789, 264.—LATH. Ind. Orn. 22.—IB. Gen. Hist. I, 162.—DAUD. Tr. Orn. II, 76.—STRICKL. Orn. Syn. I, 1855, 83. Two specimens examined, from Japan (Nat. Mus., 1; Philad. Acad., 1).

[54] _Falco communis_, var. _communis_ (GMELIN). _Falco communis_, GMEL. S. N. 1789, 270.—SCHLEG. Krit. übers, p. 14.—IB. Mus. Pays-Bas, 1862, _Falcones_, 1.—PELZ. Ueb. der Geier und Falk. 1863, 23. _Falco peregrinus_, GMEL. S. N. 1789, 272.—STRICKL. Orn. Syn. I, 81, et AUCT. Seventeen specimens of this race have been examined. They are distributed as follows: Nat. Mus., 5; Bost. Soc., 6; Philad. Acad., 4; Cambridge Mus., 2. Total, 17.

[55] _Falco communis_, var. _melanogenys_ (GOULD). _Falco communis_, LATH. New S. Wales Dr. II, No. 4. _Falco peregrinus_, VIG. LINN. Trans. XV, p. 183.—IB. Isis, 1830, 260.—BONAP. Consp. 23, No. 2. _Falco melanogenys_, GOULD, P. Z. S. pt. 5, 1837, 139.—IB. Synop. B. Austr. pt. 3, pl. xl, fig. 2; Birds of Austr. I, pl. 8; Intr. B. Austr. 19.—GRAY, Gen. B. fol. sp. 6.—IB. List. B. Brit. Mus. 51.—BONAP. Rev. Zoöl. 1850, 484.—KAUP, Monog. Falc. in Jardine’s Contr. Orn. 1850, 56.—STURT, Exp. Austr. App. 14.—STRICKL. Orn. Syn. I, 1855, 84.—GRAY, Hand List, I, 1869, 19, No. 167. _Falco macropus_, SWAINS. An. Menag. 1838, 341. Eight specimens examined, including the types of GOULD’S figures and descriptions in the Birds of Australia.

[56] _Falco aurantius_, GMEL. (Rufous-bellied Falcon). _Falco aurantius_, GMEL. Syst. Nat. p. 283, 1789.—LATH. Ind. Orn. p. 48, 1790, Gen. Hist. I, 289.—DAUD. Tr. Orn. II, 130.—SHAW, Zoöl. VII, 194.—STEPH. Zoöl. XIII, ii, 40.—CUV. Reg. An. (ed. 2), I, 322.—LESS. Tr. Orn. p. 91. BONAP. Consp. Av. p. 25.—STRICKL. Orn. Syn. I, 89, 1855. _Hypotriorchis aurantius_, KAUP, Ueb. Falk. Mus. Senck. p. 257, 1845. _Bidens aurantius_, SPIX, Av. Bras. I, 17, 1824. _Falco deiroleucus_, TEMM. Pl. Col. 348, 1836.—LESS. Man. Orn. I, 79.—GRAY, List B. Brit. Mus. 1844, p. 25; Gen. B. fol. sp. 12.—BONAP. Rev. Zool. 1850, 486. _Falco rufigularis_ (not of DAUDIN!) GRAY, List B. Brit. Mus. p. 54, 1844.

SP. CHAR. _Adult_ (♂, Costa Rica; Coll. G. N. Lawrence). Above bluish-plumbeous, the feathers darker centrally; anteriorly the black increases in extent, first leaving the plumbeous only as a border to the feathers, and then dropping it altogether, the head and nape being plain black; posteriorly the plumbeous predominates, and shows a tendency to form transverse bars. On the head and neck the black occupies the whole upper and lateral portions, reaching down to the throat, involving the whole of the cheeks and maxillæ, which it covers in an angular patch. Primaries and tail deep black; the former immaculate on their outer surface; the latter crossed by six (the last terminal) incomplete very narrow bands of pure white, formed by transverse bars, which touch neither the shaft nor edges of the feathers; upper tail-coverts crossed by about two bars of pure white. Immaculate area of the throat and jugulum deep rufous posteriorly and laterally, pure white anteriorly and centrally; from the jugulum to the tibiæ, and including the entire lining of the wing, continuous black, with transverse bars of white; tibiæ plain rufous; crissum mixed rufous and white,—the former predominating,—and thickly marked with large transverse spots of black; inner webs of primaries with transverse ovate spots of white, touching neither shaft nor edge of the feather; these number seven on the longest quill (second). Wing-formula, 2–1, 3–4. Wing, 9.90; tail, 5.50; tarsus, 1.55; middle toe, 1.75.