_Tinnunculus_, VIEILL. 1807. (Type, _Falco tinnunculus_, LINN.
_Tinnunculus alaudarius_, GMEL.)
_? Tichornis_, KAUP, 1844. (Type, _Falco cenchris_, NAUM.)
_Pœcilornis_, KAUP, 1844. (Type, _Falco sparverius_, LINN.)
The characters of this subgenus have been sufficiently defined in the
diagnosis on page 1427, so that it will be necessary for me only to add
a few less important ones.
[Illustration:
=53198=, ♀.
=53198=, ♀. ½
=53198=, ♀.
=53198=, ♀. ½
_Tinnunculus sparverius._]
The subgenus _Tinnunculus_ is one which is well characterized by
peculiarities of manners and habits as well as by features of structure.
The species are the most arboreal of the Falcons, and their curious
habit of poising in a fixed position as they hover over some object of
food which they are watching is probably peculiar to them, and has been
remarked of the Old World as well as of the American species. In their
structure they are the most aberrant members of the subfamily belonging
to the Northern Hemisphere and in their weak bill and feet, lengthened
tarsi, obtusely tipped quills, more rounded wings, and more lengthened
tail, exhibit a decided step toward _Hieracidea_, an Australian genus
which is almost exactly intermediate in all the characters of its
external structure between the true Falcons and the South American genus
_Milvago_, of the Polyborine group.
The subgenus is most largely developed in the Old World, where are found
about a dozen nominal species, of which perhaps one half must be reduced
to the rank of geographical races. America possesses three species,
two of which are restricted to the West India islands, while the other
extends over the entire continent.
There is no reason whatever for separating the American species from
those of the Old World, and the subgenus _Pœcilornis_, established upon
these by Kaup, is not tenable.
Since the publication of my first paper upon the American forms of
_Tinnunculus_,[59] a large amount of additional material has fallen
under my observation; the total number of examples critically examined
and compared together amounting to over three hundred and fifty skins of
which I have kept a record, besides many others which have come casually
to my notice. This abundant material merely confirms the views I first
expressed, in the paper alluded to, regarding the number and definition
of the forms; their comparative relation to each other being the only
respect in which I have reason to modify my arrangement.
In my first paper on the American _Tinnunculi_, three distinct
species were recognized; one (_sparverius_) belonging to the whole
of Continental America and the Lesser Antilles, one (_leucophrys_,
Ridgway) to Cuba and Hayti, and one (_sparveroides_, Vig.) peculiar
to Cuba. The first is one modified in different climatic regions into
several geographical races, as follows: Var. _sparverius_, L., North
and Middle America, exclusive of the gulf and Caribbean coast region;
var. _isabellinus_, Swains., the eastern coast region of Tropical
America, from Guiana to Florida; var. _dominicensis_, Gmel. (Lesser
Antilles); var. _australis_, Ridgw. (South America in general); and
var. _cinnamominus_, Swains. (Chile and Western Brazil). That each of
these races is well characterized, the evidence of a series abundantly
sufficient to determine this point enables me to assert without reserve;
for I find in each instance that the characters diagnosed in my synopsis
hold good as well with a large series as with a few specimens.
The following synopsis, essentially the same as that before published,
may, to most persons, explain satisfactorily my reasons for recognizing
so many races of _T. sparverius_,—a proceeding which, I am sorry to
say, does not meet with favor with all ornithologists.[60] Though
there are at the present time three well-characterized or permanently
differentiated species of _Tinnunculus_ on the American continent,
yet it is, to my mind, certain that these have all descended from a
common ancestral stock, for evidence in proof of this is found in many
specimens which I consider at least strongly “suggestive” of this fact;
some specimens of var. _isabellinus_ from Florida having blue feathers
interspersed over the rump, thereby showing an approximation toward the
uniformly blue upper surface of the adult male of _T. sparveroides_ of
the neighboring island of Cuba; while in the latter bird the embryonic
plumage of the male is very similar to the permanent condition of the
male of _sparverius_.
Synopsis of the American Species.
=A.= Back always entirely rufous (with or without black bars.) Lower
parts white, or only tinged with ochraceous; front and auriculars
distinctly whitish.
_a._ Inner webs of primaries barred entirely across, with white and
dusky; “mustache” across the cheeks conspicuous; no conspicuous
superciliary stripe of white.
1. =T. sparverius.=[61] Crown bluish, with or without a patch
of rufous. ♂. Wings and upper part of head slaty, or ashy-blue;
scapulars, back, rump, and tail reddish-rufous; primaries, basal
half of the secondaries, and a broad subterminal zone across the
tail, black. ♀. The bluish, except that of the head, replaced by
rufous, which is everywhere barred with blackish, and of a less
reddish cast. _Hab._ Entire continent of America, also Lesser
Antilles, north to St. Thomas.
_b._ Inner webs of primaries white, merely serrated along the
shaft with dusky; “mustache” obsolete or wanting; a conspicuous
superciliary stripe of white.
2. =T. leucophrys.=[62] Similar to _sparverius_, except as
characterized above. _Hab._ Cuba and Hayti.
=B.= Back rufous only in the ♀. Lower parts deep ferruginous-rufous;
front and auriculars dusky.
3. =T. sparveroides.=[63] ♂. Above, except the tail, entirely dark
plumbeous, with a blackish nuchal collar; primaries and edges
and subterminal portion of tail-feathers, black. Beneath deep
rufous (like the back of _sparverius_ and _leucophrys_), with a
wash of plumbeous across the jugulum; throat grayish-white. Inner
webs of primaries slaty, with transverse cloudings of darker. ♀.
Differing from that of the above species in dark rufous lower
parts and dusky, mottled inner webs of primaries. Second and third
quills longest; first shorter than or equal to fourth. _Hab._ Cuba
(only?).
The distinguishing characters of _F. sparverius_ having been given in
the foregoing synopsis, I will here consider this species in regard
to the modifications it experiences in the different regions of its
geographical distribution.
The whole of continental America, from the Arctic regions to almost the
extreme of South America, and from ocean to ocean, is inhabited, so far
as known, by but this one species of _Tinnunculus_. But in different
portions of this vast extent of territory the species experiences
modifications under the influence of certain climatic and other local
conditions, which are here characterized as geographical races; these,
let me say, present their distinctive characteristics with great
uniformity and constancy, although the differences from the typical
or restricted _sparverius_ are not very great. The _F. sparverius_ as
restricted, or what is more properly termed var. _sparverius_, inhabits
the whole of North and Middle America (both coasts included, except
those of the Gulf of Mexico and Caribbean Sea), south to the Isthmus of
Panama. Throughout this whole region it is everywhere nearly the same
bird. This variety appears to represent the species in its greatest
purity, being a sort of central form from which the others radiate.
The most typical examples of the var. _sparverius_ are the specimens
in the large series from the elevated regions or plateau of Mexico and
Guatemala. In these the rufous of the crown is most extended (in none is
it at all restricted), and the ashy portions are of the finest or bluest
and lightest tint.
All specimens, of quite a large series, from the peninsula of Lower
California, are considerably smaller than any others, the smallest
(1,693 ♂ ad. San José; J. Xantus) measuring, wing, 6.50; tail, 4.20,
and tarsus, 1.30; the dwarfed size of these, however, is their only
distinguishing feature. Two specimens (50,199, ♂, Cape Florida, and
10,345, ♀, Indian Key) from Florida differ from others in the unusual
development of the bill, which toward the end is more suddenly curved,
and the point considerably lengthened; these specimens have, also, only
a tinge of rufous on the crown, thus showing a proximity to the var.
_isabellinus_. The large bill, however, is no more than would be looked
for in specimens from that region.
Along the Gulf border of the United States, and the Caribbean and North
Atlantic coasts of South America (probably the whole Atlantic coast of
tropical and subtropical America), the true _sparverius_ is changed into
what Swainson has called “_Falco isabellinus_,” which differs from the
former only in having the cinereous of the crown and wings considerably
darker (as well as less bluish), approaching plumbeous; the rufous of
the crown is totally absent, or only present in faint touches; the lower
parts are of a deeper ochraceous, and the black spots on the breast and
sides sparse.
Allied to the last in tints of coloration, and apparently a direct
offshoot from it, is the _dominicensis_ of Gmelin (based upon
description by Brisson), which inhabits the Lesser Antilles, from
Trinidad northward to Porto Rico. Although I consider this (var.
_dominicensis_) as a modified form of the var. _isabellinus_, yet it is
the one of all the varieties referrible to _sparverius_ which deviates
most widely from the typical or original style. The characters of this
are, tints those of var. _isabellinus_, but, in addition, the tail has
numerous more or less complete black bands, while those of the back and
scapulars are very broad and numerous; also, the crown has a decided
rufous patch; the bill, too, is larger than in any other American member
of the genus. A style of considerable uniformity spreads over the whole
of South America, including both coasts, from Bogota to the Parana,
excepting the northeastern coast region, before mentioned as inhabited
by the var. _isabellinus_. It differs from all the other styles, except
the _cinnamominus_ of Chile, in having the lower parts continuously dull
white, any ochraceous tinge being scarcely perceptible; there is seldom
a trace of rufous on the crown, which has the light bluish tint seen
in var. _sparverius_, and the black zone of the tail is scarcely more
than half as wide as in the northern races. In size, also, it somewhat
exceeds the others. Swainson named this “_Falco gracilis_”; but the _F._
(_Tinnunculus_) _gracilis_ of Lesson being a different species, and the
name as applied to it of prior date, I have bestowed upon the present
bird the name var. _australis_.
In Chile and Brazil (Western ?) we find a form resembling the last in
some respects, but differing in points of almost specific value. It
differs from all the other American members of the genus in having
the tail continuously rufous to the extreme tip, the black zone being
considerably narrower than the terminal rufous, the lateral tail-feather
immaculate rufous, etc. The grayish of the head is much darker and more
slaty than in the var. _australis_. This is, without doubt, the _Falco
cinnamominus_ of Swainson, the specimens in the collection corresponding
exactly with the description by that author.
The rufous patch on the crown must not be too much considered, as it
is of all characters perhaps the most treacherous, though its presence
or absence is in a measure characteristic of the several varieties.
Neither does the exact number of spots on the lateral tail-feather
prove sufficiently constant to serve as a character in which the least
reliance can be placed, though Swainson attaches considerable value to
it. I have found that, besides varying almost with the individual, in
some specimens the feathers of opposite sides did not correspond.
About two hundred and fifty specimens form the basis of the following
synopsis.
=A.= Tail tipped with white; outer tail-feathers (one or more)
variegated.
_a._ ♂. Head above, and wings, fine bluish-ash; usually one
tail-feather only (the outer) variegated.
1. Vertex with a conspicuous patch of rufous. ♂. Black zone of the
tail 1.00 in width; breast strongly tinged with ochraceous; spots
of black on the breast or sides circular. ♀. Above fulvous-rufous,
the whole breast and sides with longitudinal dashes of a lighter
tint of the same. _Hab._ Continent of North America north of
Panama (except Caribbean and Gulf coast) …
var. _sparverius_.
2. Vertex with only a trace of rufous, or none at all. ♂. Black
zone of tail only .60 in width; breast nearly pure white;
spots of black usually only on the sides, elliptical. ♀. Above
vinaceous-rufous; longitudinal markings beneath deeper brown.
_Hab._ Continent of South America (except North Atlantic and
Caribbean coast) …
var. _australis_.[64]
_b._ ♂. Head above, and wings, dark bluish-plumbeous; several outer
tail-feathers variegated.
3. Vertex without any rufous. ♂. Anterior portions beneath deep
ochraceous, without spots. Tail without indication of bars
anterior to the subterminal one; black bars above confined to
larger scapulars. ♀. Above ferruginous, with the black bars
broader and blacker than in either of the preceding. _Hab._ Gulf,
Caribbean, and Atlantic coasts of tropical continental America
(Florida to Cayenne) …
var. _isabellinus_.
4. Vertex with a patch of rufous. ♂. Black spots beneath numerous,
large and circular. Tail with more or less complete black bars
anterior to the subterminal band, sometimes regularly barred
to the base; black bars above covering entire rufous surface.
♀. Similar to that of _isabellinus_, but markings beneath more
numerous, and pure black instead of brown. _Hab._ Lesser Antilles,
north to St. Thomas …
var. _dominicensis_.[65]
=B.= Tail tipped with deep rufous; outer tail-feather unvariegated.
5. Head above dark slaty-plumbeous, without any rufous. ♂. Tail
continuous rufous to the extreme tip, the subterminal black
band narrower than the terminal rufous one, and not continuous;
the outer feather entirely rufous, without any black. In other
respects much like var. _australis_. (♀ not seen.) _Hab._ Chile
and Western Brazil …
var. _cinnamominus_.[66]
Falco (Tinnunculus) sparverius, LINN.
Var. =sparverius=, LINNÆUS.