_Certhiola_, SUNDEVALL, Vet. Akad. Handl. Stockholm, 1835, 99. (Type,
_Certhia flaveola_, LINN.
[Line drawing: _Certhiola flaveola_, Sund.]
GEN. CHAR. Bill nearly as long as the head; as high as broad at base,
elongated, conical, very acute, and gently decurved from base to tip.
Culmen uniformly convex; gonys concave. No bristles at base of bill.
Tail rounded, rather shorter than the wings. Tarsi longer than the
middle toe. Iris brown? Nest pensile and arched. Eggs with yellowish
ground dotted thickly with rufous spots.
This genus is one of those especially characterizing the West Indies,
almost every island as far as known having its peculiar species,
differing, it is true, in very slight characters, but always constant
to the normal type. Cuba alone has so far furnished no representative
of this genus, its place being supplied apparently by _Cæreba cyanea_.
The specimens from St. Thomas I cannot distinguish from those of Porto
Rico, but this is, so far as the series before me indicates, the only
case where one species occurs on two islands. All the West Indian
species, nine or ten in number, agree in having the whole upper part
nearly uniformly dusky or blackish; the head and back being
concolored, while of the three or four South American all but one (_C.
luteola_) have the back more olivaceous, the head much darker. Again,
the West Indian species, with a single exception (_C. bananivora_),
have both webs of lateral tail-feathers broadly and about equally
tipped with white; while in all the South American this white is more
restricted on the inner web, and on the outer reduced to a narrow
border. _C. caboti_ from Cozumel, near the eastern coast of Yucatan,
exhibits the Continental impress in possessing the character last
mentioned.
[Illustration: _Certhiola flaveola._
38055]
In all the species from the Greater Antilles and the portion of
Continental America west and directly south of this group, there is a
distinct external white patch at base of quills; while this disappears
in the species of the Lesser Antilles and eastern South America, or is
only faintly traceable. Again, in the species of the Lesser Antilles,
with the disappearance of the white wing-patch, the greater and middle
wing-coverts show a faint edging of lighter, by which, as well as by
the darker back, they are distinguished from their South American
allies.
The shape of the white patch at base of the quills on the outer web
furnishes, in combination with the color of the throat, excellent and
permanent specific characters. This in the Jamaican, Haytien, and
Bahaman forms is elongated, extending gradually and uniformly behind
to the outer edge of the quill, while in those of Porto Rico, St.
Thomas, Cozumel, and the South American species, where it exists, the
posterior outline is nearly transverse, and only running out a little
along outer web.
As a general rule South American species have shorter tails than the
West Indian.
It is a nice question what are really species in this genus, and what
merely races or varieties; but it would probably be not far from
correct to assume that the various forms described are simply
modifications of one primitive species, produced by geographical
distribution and external physical conditions. In the following
diagnosis I shall treat all the varieties as occupying the same rank,
without attempting any discrimination. Although but one of these
belongs to the United States, and that as a straggler from the
Bahamas, I give the table of the whole, to show the interesting
relationship between them.
COMMON CHARACTERS. Above dusky-olive or blackish; the rump
olivaceous or yellowish; the head and cheeks always black, and
sometimes darker than back. Chin and throat ashy or black. Rest
of under part yellow, duller behind. A broad white stripe from
bill above eye to nape. A white patch at base of primaries;
generally visible externally, sometimes concealed. Lateral
tail-feathers tipped with white. Bill black; legs dusky.
A. Head uniform in color with rest of upper parts; dark
sooty-brown or blackish. Both webs of outer tail-feather tipped
with white (except in _luteola_). All West Indian except
_luteola_, which, however, occurs in Tobago and Trinidad, and
generally belongs to the shores of the Carribean Sea.
1. A distinct and conspicuous external white patch at base of
primaries. Wing-coverts not margined with paler.
_a._ Throat uniformly but decided dark ash-color, varying in
shade, never entirely black, however, nor ashy-white.
Throat very dark ash, not contrasting or appreciably
different from blackish of cheeks.
Wing-spot elongated; the white running out gradually
and obliquely behind to the outer edge of the
primary, reaching shaft of outer primary. Yellow of
breast decidedly ochraceous. Rump as bright yellow
as the belly. _Hab._ Jamaica … _flaveola_.[83]
White patch of wing more quadrate on each quill;
transverse; not tapering off gradually and uniformly
behind; not reaching the shaft on outer primary.
Breast without ochraceous; rump olivaceous-yellow;
the color different from that of belly. _Hab._ Santa
Cruz … _newtoni_.[84]
_b._ Chin and throat lighter ash (but not at all whitish); in
decided and appreciable contrast with blackish of cheeks.
Jugulum yellow, like under parts generally.
Lateral tail-feather broadly tipped with white on both
webs. Rump olivaceous-yellow.
Wing-spot on each primary nearly quadrate, as in
_newtoni_. _Hab._ Porto Rico and St. Thomas …
_portoricensis_.[85]
Lateral tail-feather with inner web only broadly tipped
with white. Rump bright yellow like belly. Bill very small.
White of wing as in _flaveola_, but less extended, and
margining edge only of outer primary. _Hab._ Hayti and
St. Domingo … _bananivora_.[86]
White of wing as in _newtoni_. Size much larger; darker
above. _Hab._ Tobago, Trinidad, and north shore of South
America … _luteola_.[87]
_c._ Chin, throat, and jugulum white, with a tinge of ashy.
Yellow of under parts much restricted.
Depth of bill less than half distance from nostril to tip.
Superciliary stripe reaching to nape. Yellow of under part
restricted to a triangular patch on breast. White spot on
wing large, tapering off gradually on each primary, as in
_flaveola_; on the outer reaching shaft. Both webs of outer
tail-feather about equally tipped. _Hab._ Bahamas and
Florida Keys … _bahamensis_.[88]
Depth of bill fully half distance from nostril to tip.
Superciliary stripe reaching the occiput only. Yellow of
under parts more extended. White spot on wing restricted;
more quadrate, as in _newtoni_; edge only of outer primary
involved. Outer web of outer tail-feather scarcely tipped.
_Hab._ Cozumel Island, Yucatan … _caboti_.[89]
2. No external white patch at base of primary quills.
Wing-coverts obscurely margined with paler. Both webs of outer
tail-feathers tipped about equally with white. Rump olivaceous;
this color of but slight extent.
_a._ Throat black; continuous with black of cheeks; or else
very dark plumbeous, scarcely distinguishable from the
cheeks.
Median line of throat white, the sides black like the
cheeks; chin alone black. Superciliary stripes not
confluent anteriorly. _Hab._ Martinique … _martinicana_.[90]
Whole throat blackish. No white frontal band?
Wing 2.50 inches. Belly ochraceous. _Hab._ Dominica
Island, West Indies … _dominicana_.[91]
Wing 2.20 inches. Belly more yellow. _Hab._ Barbadoes …
_barbadensis_.[92]
Whole throat very dark plumbeous. A whitish frontal broad
band connecting the superciliary stripes which extend in
front of the eye. _Hab._ Antigua, West Indies …
_frontalis_.[93]
A grayish frontal band; superciliary stripes narrow; not
extending in front of eye. Trace of white patch at base of
primaries … _bartholemica_.[94]
B. Head blackish, in distinct contrast to the more olivaceous
back. Outer tail-feather with outer web scarcely tipped with
white. Wing-coverts not margined with paler. Throat light ash, in
distinct contrast to black of cheek.