Part 12

Dr. Suckley obtained a specimen near Fort Benton, on the Upper Missouri, in Dakotah, and Dr. Cooper procured others thirty-five miles west of Fort Kearney, in Nebraska, in August. He saw them in great numbers on the plains of Nebraska, and did not observe any difference in habits between them and the birds of California.

This species was found in Texas, near Fort Davis, and also at El Paso, by Mr. J. H. Clark. It was taken in Tamaulipas, Mexico, by Lieutenant Couch. Mr. Clark remarks that they were seen by him only in the prairie-dog towns, and were found in conjunction with the rattlesnake, and accuses them of feeding upon the young of the prairie-dog; but this ungrateful requital of the hospitality given them in the burrows of this marmot is discredited by Dr. Kennerly and others, who regard the apparent harmony in which the two dwell together as altogether incompatible with this habit.

This species is also found on our Pacific coast, west of the Rocky Mountains, as far north as British Columbia. Mr. Lord met with it along the entire course of the boundary-line. It was not by any means plentiful, but pairs of them were occasionally seen. While in camp at the Dalles he dug out several squirrel-holes. In one he found two eggs of this species, the female bird, a racer-snake, and a female ground-squirrel (_Spermophilus douglassi_). The Owl he found to be strictly of diurnal habits, feeding principally on crickets, grasshoppers, large beetles, and larvæ. He thinks it never captures small animals or birds, and regards it as a peaceful and harmless bird.

Dr. Kennerly met with this species near Los Angeles, California. At any hour of the day they might be seen seated upon the mounds erected around the holes of the marmot, or else with head protruding from its orifice, disappearing immediately when approached. When molested, they commence bowing and chattering in a somewhat ludicrous manner at the intruder, or fly swiftly away, keeping near the earth and alighting suddenly in the vicinity of a burrow to renew these amusing motions. He found it very abundant in the valley of the San Gabriel River, where it associated with the large ground-squirrel of that region.

Dr. Heermann, who found them common on the extensive open prairies, speaks of its sight as very clear by day, and adds that it will not allow the hunter on foot to approach within shooting distance; but that, if approached on a horse or a mule, it may be easily shot. The nests he found were formed of a few straws carelessly thrown together at the bottom of its tortuous burrow, which is from six to eight feet in length. The eggs were usually four in number, and are described as nearly spherical, and as pure white.

Dr. Townsend states that this Owl resorts to the forsaken burrows of marmots and badgers, but never lives on terms of intimacy with either. The nest he describes as of fine grass, and placed at the extremity of the hole. The eggs are uniformly four in number, pale white, and about the size of those of the common House Pigeon.

Dr. Gambel, who observed this bird in California, states that he has occasionally found it in solitary burrows, and also that it often makes use of the holes dug by the _Spermophilus beecheyi_. They occasionally dig their own burrows, and live in scattered companies of four or five. Dr. Gambel also states that the bird is a resident of California throughout the year.

Mr. Darwin, in the Zoölogy of the Beagle, met with the var. _cunicularia_ in crossing the pampas of South America. In Banda Oriental, he says, it is its own workman, and excavates its burrows on any level spot of sandy soil; but in the pampas, or wherever the Bizcacha is found, it uses those made by that animal. It usually preys on mice and reptiles. Lieutenant Gilliss gives a similar account of it, from observations made in Chile.

Mr. Nathaniel H. Bishop met with _cunicularia_ on the banks of the river San Juan, in Banda Oriental, where a few pairs were seen, devouring mice and insects. After crossing the river Las Vacas, and coming upon a sandy waste covered with scattered trees and low bushes, he again encountered it. Upon the pampas of the Argentine Republic they were found in great numbers, from a few miles west of Rosario to the vicinity of San Luis, where the pampas end. On these immense plains of grass it lives in company with the Bizcacha (_Lagostomus trichodactylus_), dwelling with it in perfect harmony, and during the day, while the animal is sleeping, a pair of Owls stand a few inches within the main entrance of the burrow, and at the first sound, be it near or distant, leave their station and remain outside the hole, or upon the mound that forms the roof of their domicile. At the approach of man, both birds, with their irides dilated, mount above him in the air, and keep up an alarm-note until he passes. Then they quietly settle down in the grass, or return to their former place. On the pampas Mr. Bishop did not observe them taking their prey during the daytime, but as soon as the sun had set, the Bizcacha and Owls both leave their holes in search of food, the young of the former playing about the birds as they alight near them. They do not associate in companies, there being but one pair to a hole. Each couple keep separate from their neighbors, and at night do not stray from their homes.

It is both diurnal and nocturnal, and feeds at all hours. Outside the town of San Juan, which lies upon the eastern base of the Andes, Mr. Bishop had a fine opportunity to watch their habits in a locality differing entirely from the pampas. The country around San Juan is a dreary desert, covered with low thorn-trees, and over this waste a few Owls are found, principally near the town itself, in the vicinity of the pastures that are cultivated by irrigation. They mate in September and October. “One evening,” Mr. Bishop writes, “I was attracted by a strange sound that I supposed proceeded from a frog, but it proved to be the love-note of a little _Athene cunicularia_, and which was answered by its mate. It alighted upon a post, and commenced turning around upon it, with throat dilated, and emitting a guttural sound. These antics were continued for more than a minute, it occasionally bowing its head in a mysterious manner. The female soon after joined it, and they flew away. Each night it perched upon a tall flagstaff and uttered its love-note. Close by the house was a lagoon, the borders of which were swampy, and over this a pair often hovered in search of food. I watched one that kept on the wing for nearly two hours, some fifty feet from the ground, and during that time did not change its position in any other way than by rising or falling a few feet. A boy brought me a female with five eggs, that had been taken from a burrow five feet from the mouth. The bird was very fierce, and fought me with her wings and beak, uttering all the while a long shrill note, resembling a file drawn across the teeth of a saw. I supplied her with eleven full-grown mice, which she devoured during the first thirty-six hours of her confinement. It is said to place a small nest of feathers at the end of the hole, in which are deposited five white eggs.”

The eggs of the var. _cunicularia_ are of a rounded-oval shape, more obtuse at one end than at the other, measure 1.30 inches in length by 1.05 in breadth, and are of a uniform white color, with a slightly bluish tinge.

The egg of the _A. hypogæa_ is of a rounded-oval shape, equally obtuse at either end, and averages 1.35 inches in length by 1.13 in breadth, and is of a uniform clear white color. This description is taken from an egg obtained by Mr. E. S. Holden near Stockton in California. Captain Bendire writes that he has found as many as nine, and once even ten, eggs in the nest of the North American species.

NOTE.

The crania of the Owls present many features of interest, which may serve a good purpose in the definition of the sections and the genera, and to which attention has been occasionally called in the preceding pages. The tendency to asymmetry is especially marked in some species, and the better to illustrate this and other features we append several plates, in which the corresponding views are placed side by side.[39] The figures and accompanying lettering tell their own story, without any necessity of a labored description.

R. R.

FAMILY FALCONIDÆ.—THE FALCONS.

CHAR. Eyes directed laterally, and eyelids provided with lashes. Toes invariably naked, and tarsus usually naked and scutellate (feathered only in _Aquila_ and _Archibuteo_). Outer toe not reversible (except in _Pandion_). Head never with ear-tufts, and never wholly naked (except in the _Vulturinæ_, of the Old World).

The above characters are about the only readily observable points in the external anatomy in which the _Falconidæ_ differ strikingly from the _Strigidæ_ and _Cathartidæ_, and may serve to distinguish the birds of this family from those of the two others. The osteological characters, however, as expressed on page 1328, are more decided and important in a taxonomic point of view, and serve to separate the Hawk family as a well-defined group.

In the following treatment of the North American _Falconidæ_, I confine that part relating to the systematic arrangement strictly to the species embraced within the province of our work, for the reason that in a forthcoming monograph of all the American species I hope to present a systematic classification based upon the species of the whole world. All preliminary details regarding the general characteristics and distinctive peculiarities of the family, as well as all discussions and generalizations upon the subject, will therefore be omitted here.

The following synopsis of the North American genera is intended as an artificial arrangement which may enable the student to identify, by simple and readily understood characters, the forms belonging to this country.[40]

Genera.

=A.= Nasal bones almost completely ossified, the nostril being a small orifice, with a conspicuous central bony tubercle; its form nearly or quite circular, or linear and oblique (in Polyborus), with its upper end the posterior one …

_Falconinæ._

1. =Falco.= Nostril circular. Commissure with a prominent tooth and notch; lower mandible abruptly truncated and notched. Primaries stiff and hard, and more or less pointed, the first to the second longest, and the outer one or two with their inner webs cut, the angular emargination being near the end of the quill. Middle toe much more than half as long as the tarsus; claws strongly curved, very acute.

2. =Polyborus.= Nostril linear, oblique, the upper end the posterior one; commissure without prominent tooth nor notch; lower mandible not distinctly truncated or notched. Primaries soft, obtuse, the third longest, and the outer four or five with their inner webs cut, the shallow sinuation being toward the middle of the quill. Middle toe less than half the tarsus; claws weakly curved, very obtuse. Face and cheeks naked, and scantily haired.

=B.= Nasal bones very incompletely ossified, the nostril being a large, more or less oval, opening, of oblique direction, its lower end being invariably the posterior one; without a bony tubercle, and never perfectly circular. (_Accipitrinæ._)

_a._ Sides of the head densely feathered close up to the eyelids.

3. =Pandion.= Outer toe reversible; claws contracted and rounded on their under surface, and not graduated in size.[41] Wing long, third quill longest; outer four with inner webs emarginated. Tail rather short, rounded.

4. =Nauclerus.= Outer toe not reversible; claws not contracted or rounded on under side, and graduated in size. Wing long, third quill longest; outer two with inner webs sinuated. Tail excessively lengthened and forked, the lateral pair of feathers more than twice as long as the middle pair.

_b._ Sides of the head with a more scantily feathered orbital space, with a projecting superciliary “shield” covered with a naked skin.

* A well-developed membrane, or “web,” between the outer and middle toes at the base.

† Tarsus about equal to the middle toe.

§ Claws short and robust; two outer quills with their inner webs cut.

5. =Ictinia.= Commissure irregularly toothed and notched; front of tarsus with transverse scutellæ. Tail emarginated; third quill longest.

6. =Elanus.= Commissure without irregularities; front of tarsus with minute roundish scales. Tail double-rounded; second quill longest.

§§ Claws long and slender; five outer quills with inner webs cut.

7. =Rostrhamus.= End of bill bent downward, with a long pendent hook; inner edge of middle claw slightly pectinated, or serrated. Tail emarginated; third or fourth quill longest.

†† Tarsus very much longer than the middle toe.

¶ Front of tarsus unfeathered, and, with the posterior face, covered with a continuous series of broad transverse scutellæ.

α. Form very long and slender, the head small, the tail and legs long and claws excessively acute; bill weak, compressed, very high through the base, the culmen greatly ascending basally, and the cere much arched; commissure usually with a very prominent “festoon.”

8. =Circus.= Face surrounded by a “ruff” of stiffened, differently formed feathers, as in the Owls. Tarsus more than twice as long as the middle toe. Wing very long, hardly concave beneath; third to fourth quill longest; outer four with inner webs sinuated.

9. =Nisus.= Face not surrounded by a ruff. Tarsus less than twice as long as the middle toe. Wing short, very concave beneath, the outer quill much bowed; third to fifth quills longest; outer five with inner webs sinuated.

β. Form short and heavy, the head larger, the tail shorter, the legs more robust. Bill stronger, less compressed, lower through the base, the upper outline less ascending basally, and the cere less arched. Commissure variable.

10. =Antenor.= Form heavy, the wings and tail moderately long, and feet very robust; bill rather elongated, the commissural lobe prominent, and the base of the culmen somewhat depressed. Fourth quill longest; outer five with inner webs cut. Lores naked, and almost destitute of bristles.

11. =Onychotes.= Outstretched feet reaching beyond end of tail; tibial plumes short, close, not reaching below the joint. Wing short, rounded, very concave beneath, the fourth quill longest; outer five with inner webs sinuated. Tail short, but little more than half the wing, slightly rounded. Claws very long, and extremely acute.

12. =Asturina.= Bill and feet as in _Antenor_; lores densely bristled; wing short, rounded, concave beneath, the third to fourth quills longest; outer four with their inner webs cut.

13. =Buteo.= Form of _Antenor_, but primaries longer and more pointed, the fourth usually longest, and the outer three or four with inner webs cut. Bill and feet as in _Asturina_. Tail moderate, or rather short, nearly even, or slightly rounded.

¶¶ Front of the tarsus densely feathered down to the base of the toes.

14. =Archibuteo.= Feathering of the tarsus interrupted behind by a bare strip along the full length; middle toe less than half as long as the tarsus. Nostril broadly oval, obliquely horizontal; bill weak, the upper outline of the cere much ascending basally. Feathers of the nape normal, blended. Third to fourth quills longest; outer four or five with inner webs cut.

15. =Aquila.= Feathering of the tarsus uninterrupted behind; middle toe more than half as long as the tarsus. Nostril narrowly oval, obliquely vertical; bill strong, the upper outline of the cere nearly parallel with the lower. Feathers of the nape lanceolate, distinct. Fourth quill longest; five to six with inner webs cut.

** No trace of membrane between outer and middle toes.

16. =Haliætus.= Tarsus feathered in front one third, or more, of the way down; the naked portion with an imperfectly continuous frontal, and less well defined posterior, series of transverse plates, and covered elsewhere with roundish granular scales. Feathers of the neck, all round, lanceolate, distinct. Bill very large, the chord of the culmen more than twice as long as the cere on top; nostril oval, obliquely vertical. Third to fifth quills longest; outer six with inner webs cut. Tail rounded or cuneate, sometimes consisting of fourteen feathers.

The foregoing diagnoses embrace merely the more conspicuous external characters whereby the genera may be most readily distinguished by the student. The following table presents additional accompanying characters afforded by the osteological and anatomical structure, of more importance in defining with precision the several groups embraced in our fauna.

=A.= Scapular process of the coracoid produced forward so as to meet the clavicle[42] (HUXLEY). Nasal bones almost completely ossified, the nostril being a small, usually circular opening, with a raised or “rimmed” margin, and conspicuous, usually central, bony tubercle. Inferior surface of the supermaxillary bone with a prominent median angular ridge. Superciliary process of the lachrymal consisting of a single piece. (_Falconinæ._[43])

=B.= Scapular process of the coracoid not produced forward so as to meet the clavicle (HUXLEY). Nasal bones incompletely ossified, the nostrils being very large, and without bony rim or tubercle. Inferior surface of the supramaxillary bone without a median ridge. Superciliary process of the lachrymal variable. (_Accipitrinæ._)

_a._ Superciliary process of the lachrymal composed of a single, excessively abbreviated piece;[44] posterior margin of the sternum with a pair of indentations, and without foramina. (_Pandion_ and _Nauclerus_.)

_b._ Superciliary process of the lachrymal double, or composed of two pieces, joined by a cartilaginous “hinge,” and reaching nearly across the orbit. Posterior margin of the sternum without indentations, and usually with a pair of foramina. (All except _Pandion_ and _Nauclerus_.)

† Septum of the orbits and nostrils incompletely ossified (the former always and the latter usually) and with foramina; posterior margin of the sternum most produced backwards laterally, and incompletely ossified, there being usually a pair of foramina. Intestinal canal short, broad, with the duodenum simple, forming a single loop (MCGILLVRAY). A well-developed “web” between the outer and middle toes. (All but _Haliætus_.)

†† Septum of the orbits and nostrils completely ossified, and without any trace of foramina; posterior margin of the sternum produced medially into a convex lobe, and without any trace of foramina. Intestinal canal extremely elongated, attenuated, with the duodenum arranged in several convolutions (MCGILLVRAY). No trace of a web between outer and middle toes. (_Haliætus._)

SUBFAMILY FALCONINÆ.

GENUS FALCO, AUCT.

GEN. CHAR. Bill strong, its breadth at the base equalling or exceeding its height; upper outline of cere on a level with, or rather lower than, the base of the culmen; gonys much arched, the chord of the arch equalling about half that of the culmen. Near the tip of the upper mandible is a prominent tooth on the commissure, and near the end of the lower mandible, which is truncated, is a deep notch corresponding; the end of the upper mandible is compressed, giving the situation of the tooth an inflated appearance when viewed from above. Nostrils circular, with a conspicuous central tubercle. Orbital region bare; projecting superciliary shield conspicuous, arched, but not very prominent. Tail shorter than wing, the feathers hard and stiff. Primaries very strong, elongated, tapering rapidly toward their points; only the first or first and second with their inner webs emarginated, the cutting being angular, and near the end of the quill. Tarsus never with a single series of transverse scutellæ either in front or behind; middle toe very long.

Subgenera.

One primary only with inner web emarginated; first to second longest; first longer than fourth.

Tarsus longer than middle toe, and feathered far below the knee; first quill shorter than third. Coloration of the sexes alike; old and young slightly different in pattern and tints. Size large …

_Hierofalco._

Tarsus not longer than middle toe, and scarcely feathered below the knee; first quill equal to or longer than the third. Coloration of the sexes alike; old and young very different in pattern and tints. Size, very small to large …

_Falco._

Two primaries with inner webs emarginated; second to third longest; first shorter than fourth.

Basal joint of toes without transverse scutellæ; tarsus about equal to middle toe.

Coloration of the sexes in adult plumage very different in tints; in the young alike, the young ♂ resembling the adult ♀. Size small …

_Æsalon._

Basal joint of toes with transverse scutellæ; tarsus longer than middle toe.

Coloration of the sexes very different, in pattern and tints, at all ages; old and young alike. Scutellæ of the toes and tarsus interrupted at the digito-tarsal joint; tarsus much longer than middle toe. Bill small, the cere on top less than one fourth the culmen. Size small …

_Tinnunculus._