Part 60

Immature female (second year, 15,260, Fort Buchanan, New Mexico; Dr. Irwin). Black spots beneath larger and more irregularly defined; tibiæ strongly barred with dark rufous; posterior edge of basal band of tail much broken.

HAB. Middle, or northern tropical, America, from the Isthmus of Panama northward into the southern United States; Mississippi (AUDUBON); Texas (Mus. S. I.; DRESSER); Arizona (COUES).

Localities: Guatemala (SCL. Ibis, I, 216).

LIST OF SPECIMENS EXAMINED.

National Museum, 13; Philadelphia Academy, 3; Cab. G. N. Lawrence, 2; Coll. R. Ridgway, 1. Total, 19.

Measurements.

+----+-----------+-----------+---------+---------+-----------+----------+ |Sex.| Wing. | Tail. | Culmen. | Tarsus. |Middle Toe.|Specimens.| +----+-----------+-----------+---------+---------+-----------+----------+ | ♂ |12.35–13.75| 9.80–10.20| .90–.95|3.15–3.20| 1.65–1.70| 8 | +----+-----------+-----------+---------+---------+-----------+----------+ | ♀ |14.25–14.50|10.80–11.00|1.08–1.10|3.40–3.75| 1.90–2.00| 6 | +----+-----------+-----------+---------+---------+-----------+----------+

HABITS. This Hawk has a very limited range within the United States, and Mr. Audubon, who was the first to meet with it there, obtained only a single specimen from Louisiana. Supposing it to be an undescribed species, he named it in honor of his friend, Mr. Edward Harris.

This species is occasionally found in the lower portions of the States of Mississippi and Louisiana, but becomes much more abundant in the southwestern sections of the latter State, and in Texas is common, especially about the mouth of the Rio Grande. In one variety or the other it is frequently met with throughout Mexico, and Central America, and is also said to be an occasional visitant of Cuba and Jamaica.

Mr. Dresser found this Hawk common throughout Texas to the Colorado River, beyond which he noticed but few. It was the only Hawk he noticed at Matamoras in the summer. He describes it as a heavy, sluggish bird, seldom seen on the wing, and subsisting, so far as he could see, entirely on carrion. All along the road from Brownsville to San Antonio, he noticed it either perched on some tree by the roadside, or busy, in company with Vultures and Caracaras, regaling on some offensive carrion. He found it breeding in the neighborhood of San Antonio, Medina, and Altascosa Rivers, having eggs in the month of May. A nest found on the 4th of May, near the Medina River, was built of sticks, very slightly lined, and was placed in a low hackberry-tree. The eggs were four in number, and described as white, with a faint bluish tinge, very sparingly spotted and blotched with red.

Other writers also agree in representing this Hawk as heavy and sluggish in habit, and as frequenting streams of water, and its food as consisting chiefly of the reptiles and smaller animals which frequent the banks of rivers and creeks. It builds its nests on low trees, in the immediate vicinity of its hunting-ground, and often over the water, constructing them of coarse flags and water-plants. The nests are usually not very large for the birds, are flattened or with very slight depressions, and the materials are very loosely put together. The eggs are from three to five in number, usually white and unspotted, occasionally with more or less of a yellowish or tawny tinge. In some instances they are faintly marked with light dashes or stains of a yellowish-brown, and, more rarely, are also marked with small blotches of sepia-brown, and with smaller dottings of purplish-drab. Their average measurement is, length 2.13, breadth 1.69 inches.

Our knowledge of the eggs of these Hawks is derived from the collection of the late Dr. Berlandier, of Matamoras, in the Province of Tamaulipas, Mexico. In the cabinet of that gentleman were several varieties, now in the possession of the Smithsonian Institution, and presented to it by Lieutenant Couch.

Onychotes gruberi.]

GENUS ONYCHOTES, RIDGWAY.

Onychotes, RIDGWAY, P. A. N. S. Philad. Dec. 1870, 142. (Type, O. gruberi, nov. sp.)

GEN. CHAR. Bill short, the tip remarkably short and obtuse, and only gradually bent; cere on top about equal to the culmen, very broad basally in its transverse diameter, and ascending, in its lateral outline, on a line with the culmen; commissure only faintly lobed. Nostril nearly circular, with a conspicuous (but not central or bony) tubercle; cere densely bristled below the nostril, almost to its anterior edge; orbital region finely bristled. Tarsus very long and slender, nearly twice the length of the middle toe; toes moderate, the outer one decidedly longer than the inner; claws very long, strong, and sharp, and curved in about one quarter the circumference of a circle. Tibial feathers short and close, the plumes scarcely reaching below the joint. Feathers of the forehead, gular region, sides, and tibiæ, with white filamentous attachments to the end of the shafts. Wing very short, much rounded, and very concave beneath; fourth quill longest; first shorter than ninth; four primaries emarginated, and one sinuated, on inner webs; five sinuated on outer webs. Tail about two thirds as long as wing, rounded. Outstretched feet reaching beyond end of tail.

This genus has no very near relatives among the American Falconidæ, nor, indeed, among those of other portions of the world. It is, perhaps, most closely related to the genus Rupornis, of South America, from which, however, it is very distinct. It is represented by a single species, the type of which, supposed to have come from California, still remains unique.

The elongated legs, reaching considerably beyond the rather short tail, the close thigh-plumes, the long and extremely acute claws (somewhat like those of Rostrhamus), with the short, rounded, and very concave wing, are its most striking peculiarities. Besides these distinguishing features, the short, thick bill, very deep through the base, and the filamentous attachments to the shafts of the feathers of certain parts of the body, are also very characteristic. The latter feature may possibly be a mark of immaturity, but I have seen nothing like it in other Raptores, and it seems to be more analogous to the nuptial ornaments seen in the Cormorants (Phalocrocoracidæ).

Species.

=O. gruberi.= Wing, 10.10; tail, 6.50; culmen, about .80; tarsus, 2.70; middle toe, 1.45; posterior claw, 1.00, its digit .80. Immature (?). Uniform grayish-umber, tinged with dull rufous on the neck; lining of the wing and tibiæ dull grayish-cinnamon. Primaries inclining to black, and showing just discernible, obscure hoary bars on their basal half. Tail brownish-gray, with a hoary cast nearer the shaft (not paler at the tip), and crossed with nine or ten narrow bars of dusky, these becoming hardly distinguishable basally and terminally. Inner webs of the primaries plain white anterior to their emargination. Head laterally and beneath obsoletely streaked with whitish. Hab. “California.”

Onychotes gruberi, RIDGWAY.

GRUBER’S HAWK.

Onychotes gruberi, RIDGWAY, Pr. Ac. Nat. Sc. Phil. Dec. 1870, p. 149.

SP. CHAR. Immature? (41,703, “California”; F. Gruber). Outstretched feet reaching beyond tail. General plumage dull dark-bistre, with a grayish-umber cast in some lights, darkest on the head above and back; the posterior lower parts paler and more reddish; throat and neck much tinged with pale rusty (this obsoletely bordering the feathers, which here have fine whitish filaments attached to the shafts); primaries uniform black. Tail like the rump, but with a more hoary tinge (not paler at the tip), and crossed with seven or eight very narrow obscure bars of darker, the last of which is distant an inch or more from the end. Lining of wing dark bistre, much tinged with rusty, this prevalent toward the edge; under surface of primaries white anterior to their emargination, beyond which they are ashy, approaching black at ends; ashy portion with distant, very obsolete, dusky bars, but the cheeks and throat streaked obsoletely with this color. No distinct white anywhere about the head or neck. Wing, 10.00; tail, 5.80; tarsus, 2.70; middle toe, 1.40; inner, .90; outer, 1.10; posterior, .80; hind claw, 1.00 (chord); inner claw, .91; on front of tarsus, twelve exposed large transverse scutellæ; only 1.70 of the tarsus exposed.

The type of this species still remains unique. It was sent to the Smithsonian Institution by Mr. Gruber, who labelled it as having been obtained in California. Nothing is known of its habits.

GENUS BUTEO, CUVIER.

Buteo, CUV. 1799. (Type, Falco buteo, LINN. = Buteo vulgaris, BECHSTEIN.) Craxirex, GOULD, 1838. (Type, Buteo galapagoensis, GOULD.) Pæcilopternis, KAUP, 1847. (Type, Falco borealis, GM.) Tachytriorchis, KAUP, 1844. (Type, Falco pterocles, TEMM.)

GEN. CHAR. Form robust and heavy, the wings long, and rather pointed, the tail moderate and rounded, the bill and feet strong. Bill intermediate between that of Astur and that of Parabuteo. Wing long and rather pointed, the third to fifth quill longest, the first shorter than eighth; three to four with inner webs emarginated. Tail moderate, slightly rounded.