National Museum, 42; Boston Society, 11; Philadelphia Academy, 10;
Museum Comp. Zoöl., 7; New York Museum, 3; G. N. Lawrence, 2; R.
Ridgway, 4. Total, 79.
_Measurements._
+----+-----------+-----------+---------+---------+-----------+----------+
|Sex.| Wing. | Tail. | Culmen. | Tarsus. |Middle Toe.|Specimens.|
+----+-----------+-----------+---------+---------+-----------+----------+
| ♂ | 7.20–7.90| 4.90–5.50| .48–.50|1.30–1.40| 1.15–1.25| 34 |
+----+-----------+-----------+---------+---------+-----------+----------+
| ♀ | 8.00–8.55| 5.50–6.00| .55–.60|1.55–1.60| 1.35–0.00| 32 |
+----+-----------+-----------+---------+---------+-----------+----------+
The plumage of the adult male, which is not as often seen as that of
the younger stages and adult female, is represented in the Smithsonian
Collection by fifteen specimens, from various parts of North America.
Of these, an example from Jamaica exhibits the purest shades of color,
though agreeing closely with some specimens from the interior of the
United States; the cinereous above being very fine, and of a light
bluish cast. The upper tail-coverts are tipped with white; the tail is
a quarter of an inch longer than in any North American specimen, one
half-inch longer than the average; the wing, however, is about the same.
A specimen from Santa Clara, California (4,475, Dr. J. G. Cooper), like
most of those from the Pacific coast, has the cinereous very dark above,
while beneath the ochraceous is everywhere prevalent; the flanks are
strongly tinged with blue; the black bars of the tail are much broken
and irregular. A specimen from Jamaica (24,309, Spanish Town; W. T.
March), however, is even darker than this one, the stripes beneath being
almost pure black; on the tail black prevails, although the bands are
very regular. Nos. 27,061, Fort Good Hope, British America, 43,136, Fort
Yukon, Alaska, and 51,305, Mazatlan, Mexico, have the streaks beneath
narrow and linear; the ochraceous confined to the tibiæ, which are of a
deep shade of this color.
[Illustration: _Falco columbarius._]
A specimen from Nicaragua (No. 40,957, Chinandega) is like North
American examples, but the reddish tinge beneath is scarcely
discernible, and confined to the tibiæ, which are but faintly
ochraceous; the markings beneath are broad and deep umber, the black
shaft-streak distinct.
In the adult female there is as little variation as in the male in
plumage, the shade of brown above varying slightly, also the yellowish
tinge beneath; the bars on the tail differ in continuity and tint in
various specimens, although they are always five in number,—the first
concealed by the coverts, the last terminal. In 19,382, Fort Simpson,
British America, and 2,706, Yukon, R. Am. (probably very old birds), the
light bars are continuous and pale dull ashy.
The young vary about the same as adults. Nos. 19,381, Big Island,
Great Slave Lake; 5,483, Petaluma, California; and 3,760, Racine,
Wisconsin,—are young males moulting, scattered feathers appearing on the
upper parts indicating the future blue plumage.
Var. suckleyi, RIDGWAY.