_Accipiter_, BRISSON, 1760.[81]
_Nisus_, CUVIER, 1799. (Type, _Falco nisus_, LINN.; _A. fringillarius_
(RAY), KAUP.)
_Jerax_, LEACH, 1816. (Same type.)
_Cooperastur_, BONAP. 1854. (Type, _Accipiter cooperi_, BONAP.)
_Hieraspiza_, 1844, _Jeraspiza_, 1851, and _Teraspiza_, 1867, KAUP.
(Type, _Falco tinus_, LATH.)
_Hieracospiza_, AGASS. (Same type.)
_Urospiza_, 1845, _Urospizia_, 1848, and _Uraspiza_, 1867, KAUP.
(Type, _Sparvius cirrhocephalus_, VIEILL.)
_Erythrospiza_, KAUP, 1867. (Type, _A. trinotatus_ (TEMM.?))
_Micronisus_, GRAY, 1840. (Type, _Falco gabar_, DAUD.)
_Nisastur_, BLAS. 1844. (Same type.)
[Illustration: =10759=, ♂. NAT. SIZE
_Nisus fuscus._]
[Illustration:
=26588=, ♀. ½
=26588=, ♀. ½
_Nisus cooperi._]
The species of this subgenus are generally of small size and slender
form; but with a graceful and apparently delicate structure they combine
remarkable strength and unsurpassed daring. They differ from the species
of _Astur_ mainly in less robust organization. The species are very
numerous, and most plentiful within the tropical regions. The Old World
possesses about thirty, and America about fifteen, nominal species.
Several South American species are intimately related to the two North
American ones, and may prove to be only climatic races of the same
species; thus, _erythrocnemis_, Gray (Hand List, p. 32, No. 305) may
be the intertropical form of _fuscus_, and _chilensis_, Ph. and Landb.
(Hand List, No. 314), that of _cooperi_. But the material at my command
is too meagre to decide this.
[Illustration: =26588=, ♀. ¼
_Nisus cooperi._]
[Illustration: =26588=, ♀. ¼
_Nisus cooperi._]
[Illustration: =10759=, ♂. ½
_Nisus fuscus._]
In consequence of the insufficient material for working up the South
American species, I shall omit them all from the following synopsis of
the North American species and races.[82]
Species and Races.
COMMON CHARACTERS. _Adult._ Above bluish slate-color; the tail with
obscure bands of darker, and narrowly tipped with white. Beneath
transversely barred with white and pinkish-rufous; the anal region
and crissum immaculate white. _Young._ Above grayish umber-brown, the
feathers bordered more or less distinctly with rusty; scapulars with
large white spots, mostly concealed; tail-bands more distinct than in
the adult. Beneath white, longitudinally striped with dusky-brown.
1. =N. fuscus.= Middle toe shorter than the bare portion of the
tarsus, in front; tarsal scutellæ fused into a continuous plate in
the adult male. Tail nearly even. Top of head concolor with the
back; tail merely fading into whitish at the tip. Concealed white
spots of the scapulars very large and conspicuous. Wing, 6.45–8.80;
tail, 5.70–8.20; culmen, .40–.60; tarsus, 1.85–2.25; middle toe,
1.10–1.55. _Hab._ Whole of North America and Mexico.
2. =N. cooperi.= Middle toe longer than the bare portion of the
tarsus, in front; tarsal scutellæ never fused. Tail much rounded.
Top of the head much darker than the back; tail distinctly tipped
with white; concealed white spots of the scapulars very small, or
obsolete. Wing, 8.50–11.00; tail, 7.50–10.50; culmen, .60–.80;
tarsus, 2.10–2.75; middle toe, 1.30–1.85. _Hab._ Whole of North
America and Mexico.
_Adult._ Rufous markings beneath, in form of detached bars, not
exceeding the white ones in width; dark slate of the pileum
and nape abruptly contrasted with the bluish-plumbeous of the
back; upper tail-coverts narrowly tipped with white; scapulars
with concealed spots of white. _Young._ White beneath pure;
tibiæ with narrow longitudinal spots of brown. Wing, 9.00–11.00;
tail, 8.00–9.80; culmen, .65–.80; tarsus, 2.45–2.75; middle
toe, 1.55–1.85. _Hab._ Eastern region of North America; Eastern
Mexico …
var. _cooperi_.
_Adult._ Rufous markings beneath, in form of broader bars,
connected along the shaft, almost uniform on the breast; black of
the pileum and nape fading gradually into the dusky plumbeous of
the back; upper tail-coverts not tipped with white, and scapulars
without concealed spots of the same. _Young._ White beneath
strongly tinged with ochraceous; tibiæ with broad transverse spots
of brown. Wing, 8.50–10.60; tail, 7.50–10.50; culmen, .60–.75;
tarsus, 2.10–2.75; middle toe, 1.30–1.75. _Hab._ Western region of
North America; Western Mexico …
var. _mexicanus_.
Nisus fuscus (GMEL.) KAUP.