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Birds of North and Middle America, part V/Genus 11. Microrhopias Sclater

 

Genus MICRORHOPIAS Sclater.

Microrhopias Sclater, Cat. Am. Birds., 1862, 182. (Type, Thamnophilus quixensis Cornalia.)

Small to very small Formicariidæ (length about 105-135 mm.) with long, graduated tail of 12 round-tipped rectrices (nearly as long as to longer than wing), tarsus much less than half as long as wing, nostril broadly oval (much broader than the narrow, sometimes nearly obsolete, operculum), the adult males with at least the chin, throat, chest, and median portion of breast black, and wing-coverts tipped with white.

Bill shorter than head, moderately stout, not compressed, its width at frontal antiæ little if any greater than its depth at same point and equal to about half the distance from nostril to tip of maxilla; culmen distinctly but not sharply ridged, nearly straight for basal half (more or less) more and more decurved terminally, the tip of maxilla slightly though distinctly uncinate; tomia straight or nearly so, distinctly notched subterminally, the notch near tip of mandibular tomium less distinct; gonys gently convex, less so terminally. Nostril exposed, longitudinally oval, nearly in contact with feathering of latero-frontal antiæ, the superior operculum very narrow or practically obsolete. Rictal bristles well developed in M. boucardi and M. consobrina,[1] very minute (practically obsolete) in M. intermedia, M. grisea, M. rufatra, and allies; feathers of chin and loral region with slender terminal setæ. Wing moderate, with longest primaries extending, more or less decidedly, beyond secondaries; fifth and sixth, sixth and seventh, or fifth, sixth and seventh, primaries longest, the tenth (outermost) one-half to three-fifths as long as the longest, the ninth shorter than secondaries. Tail nearly as long as to longer than wing, graduated (graduation equal to length of tarsus or more), the rectrices (12) rather broad, rounded terminally. Tarsus longer than whole culmen, one-third (M. boucardi, M. consobrinus) to two-fifths as long as wing (M. grisea, M. intermedia, M. rufatra), distinctly scutellate, the plantar scutella in two longitudinal series but sometimes partly fused or obsolete; middle toe, with claw, much shorter than tarsus; outer toe, without claw, reaching to slightly beyond middle of subterminal phalanx of middle toe, the inner toe slightly shorter; hallux about as long as inner toe but much stouter; basal phalanx of middle toe wholly united to outer toe, for about half its length to inner toe; claws moderate in size and curvature, that of the hallux decidedly shorter than its digit. Plumage full, lax, and blended, that of the rump and flanks elongated and more fluffy; feathers of pileum not elongated.

Coloration. — (I.) Adult males black with white spots on wing- coverts, white tips to rectrices (or lateral rectrices mostly white), and interscapulars pure white basally; adult females slate color or blackish above, with white markings as in adult males, under parts cinnamon-rufous or chestnut. (II.) Adult males brownish gray, brown, or rufescent above, the wing-coverts black with terminal white spots, the lateral rectrices also tipped with white; chin, throat, chest, and median portion of breast (sometimes abdomen also) black, the sides and flanks whitish, grayish or fulvous; adult females similar but without black on under parts.

Range. — Southern Mexico to Cayenne, southeastern Brazil, Bolivia, and Peru. (About seven species.)[2]

KEY TO THE SPECIES AND SUBSPECIES OF MICRORHOPIAS.

a. Upper parts black, the feathers of back pure white basally. (Microrhopias boucardi.)

b. White tips to lateral rectrices smaller (5-7 mm. long on outermost rectrix).
c. Flanks usually slate color. (Southeastern Mexico to Honduras.)

Microrhopias boucardi boucardi, adult male (p. 78).

cc. Flanks usually black. (Nicaragua to Panamá.)

Microrhopias boucardi virgata, adult male (p. 79).

bb. White tip to lateral rectrices larger (9-12 mm., or more, long on outermost pair). (Colombia to Cayenne and western Ecuadór.)

Microrhopias boucardi consobrina, adult male (p. 80).

aa. Upper parts not black.

b. Feathers of back abruptly pure white basally; under parts wholly tawny or chestnut. (Microrhopias boucardi.)
c. White tip to lateral rectrices smaller (about 5-7 mm. long on outermost rectrix) ; under parts lighter than chestnut, upper parts more grayish slaty.
d. Under parts tawny

Microrhopias boucardi boucardi, adult female (p. 78).

dd. Under parts deep cinnamon-rufous or rufous-chestnut.

Microrhopias boucardi virgata, adult female (p. 80).

cc. White tip to lateral rectrices larger (10-15 mm. long on outermost rectrix); under parts deep chestnut, upper parts more blackish slaty.

Microrhopias boucardi consobrina, adult female (p. 80).

bb. Feathers of back not white basally; under parts not tawny or chestnut. (Microrhopias grisea.)
c. Sides of head, throat, chest, and breast uniform black. (Adult males.)
d. General color of upper parts darker (deep grayish sepia or purplish brownish slate color).
e. White superciliary stripe narrower; white tip to wing-coverts smaller. (Cayenne to eastern Brazil.)

Microrhopias grisea grisea, adult male (extralimital).[3]

ee. White superciliary stripe broader; white tip to wing-coverts larger.
f. Flanks and sides less extensively white, the black of abdomen relatively broader. (San Miguél Island, Bay of Panamá.)

Microrhopias grisea alticincta, adult male (p. 82).

ff. Flanks and sides more extensively white, the black of abdomen relatively narrower.
g. Larger (wing 59.5, tail 52.5, tarsus 22). (Tobago.)

Microrliopias grisea tobagensis, adult male (extralimital).[4]

gg. Smaller (wing 53-54.5, tail 46-49, tarsus 20-21). (Margarita Island, Venezuela.)

Microrhopias grisea margaritensis, adult male (extralimital).[5]

dd. General color of upper parts paler (hair brown or broccoli brown). (Mainland of Venezuela and Colombia.)

Microrhopias grisea intermedia, adult male (extralimital).[6]

cc. Sides of head (below eyes) and under parts buffy or whitish. (Adult females.)
d. General color of upper parts darker (deep grayish brown); under parts distinctly buffy.
e. White tip to wing-coverts much smaller; under parts (except chin, upper throat, and under tail-coverts) deep buff or ochraceous-buff.

Microrhopias grisea grisea, adult female (extralimital).

ee. White tip to wing-coverts much larger; under parts paler buffy.

Microrhopias grisea alticincta, adult female (p. 82).

dd. General color of upper parts paler (light grayish brown); under parts dull white, tinged with buff on chest and sides.

Microrhopias grisea intermedia, adult female (extralimital).[7]

MICRORHOPIAS BOUCARDI BOUCARDI (Sclater).

BOUCARD'S ANTWREN.

Adult male. — General color deep black, passing into slate color on sides and flanks; interscapulars extensively pure white beneath the surface (partly exposed); anterior portion of lesser wing-covert area (except on bend of wing) white, the other lesser coverts and middle coverts with a small roundish terminal spot of white; greater coverts broadly tipped with white, forming a very conspicuous band across wing; rectrices (except middle pair) broadly tipped with white (the white tips growing smaller toward middle rectrices); under wing- coverts (except along border of wing) and broad edgings to inner web of remiges white; bill black; iris brown; legs and feet blackish (grayish blue in life); length (skins), 98-111 (106); wing, 47-50.5 (48.6); tail, 43-49 (45.6); culmen, 13-14.5 (13.7); tarsus, 14.5-16 (15.5); middle toe, 8.5-9 (8.9).[8]

Adult female. — Above marked with white as in adult male (that on interscapular region more restricted, however), but black of head, neck, back, and rump replaced by dark slate color or blackish slate (more or less intermixed with black on interscapular region); under parts (including malar region) plain rufous-tawny, deepest on throat and chest; under wing-coverts and edges of inner webs of remiges white, as in adult male; bill, etc., as in adult male, but the former usually more brownish; length (skins), 96-117 (107); wing, 46.5-49 (47.7); tail, 43.5-47.5 (45.6); culmen, 12.5-14.5 (13.3); tarsus, 14.5-16 (15.4); middle toe, 8.5-9.5 (8.8).[9]

Young male (nestrnig). — Above plain sooty blackish or blackish brown (nearly clove brown), rather lighter (dark sepia) on head, the wings and tail nearly black; greater wing-coverts rather broadly tipped with white but with a narrow terminal margin of dusky; rectrices (except middle pair) tipped with white, as in adults; under parts plain dark sooty brown, tinged with chestnut-brown or vandyke brown.

Southeastern Mexico, in States of Vera Cruz (Playa Vicente; Buena Vista), Oaxaca (Acatepec) and Tabasco (Teapa) through Guatemala (Choctúm; sources of Rio de la Pasión; Yzabál; Telemán; Los Amates; Uspantán, Quiché) to Honduras (Omoa; San Pedro; Rio Blanco) and British Honduras (near Manatee Lagoon; Toledo District).

Formicivora boucardi Sclater, Proc. Zool. Soc. Lond., 1858, 241, 300 (Acátepec, Oaxaca; coll. P. L. Sclater); 1859, 383 (Playa Vicente, Vera Cruz); Cat. Am. Birds, 1862, 183, pl. 16 (Oaxaca; Choctúm, Guatemala); Cat. Birds Brit. Mus., XV, 1890, 254, part (Acátepec, Oaxaca; Choctúm and sources of Rio de la Pasión, Guatemala). — Moore, Proc. Zool. Soc. Lond., 1859, 55 (Omoa, Honduras). — Sclater and Salvin, Ibis, 1859, 119 (Omoa, Honduras; Proc. Zool. Soc. Lond., 1870, 837 (San Pedro, Honduras). — Salvin and Godman, Biol. Centr.-Am., Aves, ii, 1892, 216, part (Acátepec; Playa Vicente; Choctúm, Yzabál, and Telemán, Guatemala; Omoa and San Pedro, Honduras). — Dearborn, Pub. 125, Field Mus. Nat. Hist., 1907, 109 (Los Amates, e. Guatemala).
[Formicivora] boucardi Sclater and Salvin, Nom. Av. Neotr., 1873, 72, part. — Sharpe, Hand-list, iii, 1901, 26, part.
Formicivora boucardii {{sc|Boucard]], Ann. Soc. Linn. Lyon, 1878, 39 (Guatemala; Playa Vicente, Vera Cruz).
D[rymophila] boucardi Richmond, Auk, xvi, Oct., 1899, 354, in text.

MICRORHOPIAS BOUCARDI VIRGATA (Lawrence).

PANAMA ANTWREN.

Similar to M. b. boucardi but adult male more intensely and extensively black (even the sides and flanks usually black or slate- black),[10] the adult female with color of under parts much darker (rufous-chestnut instead of rufous-tawny) and upper parts darker.

Adult male. — Length (skins), 96-113 (106); wing, 47.5-51 (49.5); tail, 40-49 (45.9); culmen, 13-14.5 (13.8); tarsus, 15-16 (15.7); middle toe, 8.5-9.5 (8.9).[11]

Adult female. — Length (skins), 96-109 (103); wing, 45-52 (48.2); tail, 40-46.5 (42.1); culmen, 12.5-14 (13.5); tarsus, 15-17 (15.8); middle toe, 8.5-10 (9.1).[12]

Nicaragua (Chontales; Los Sábalos; Rio Escondido; San Emilis), Costa Rica (San Carlos; Pejé; Pacuare; La Balsa; Talamanca; Sipúrio; Rio Sícsola; Jiménez; Angostura; Guápiles; Guacimo; Siquirres; La Cristina; Tuís; El Hogár; San José; La Concepción; La Florída; Pozo Azúl de Pirrís; Pozo del Pitál; Pozo del Rio Grande; Paso Reál; Lagarto; Boruca; Buenos Aires; Palmár; El Generál; La Vijágua), and Panamá (Divala and Bugaba, Chiriquí; Panamá; Lion Hill).

Formicivora boucardi (not of Sclater, 1858) Sclater and Salvin, Proc. Zool. Soc. Lond., 1864, 356 (Panamá; crit.). — Salvin, Proc. Zool. Soc. Lond., 1870, 195 (Bugaba, Panamá); Ibis, 1872, 318 (Chontales, Nicaragua). — Boucard, Proc. Zool. Soc. Lond., 1878, 61 (San Carlos, Costa Rica). — Nutting, Proc. U. S. Nat. Mus., vi, 1884, 405 (Los Sábalos, Nicaragua; habits). — Sclater, Cat. Birds Brit. Mus., xv, 1890, 254, part (Chontales, Nicaragua; Pejé and Angostura, Costa Rica; Panamá, Bugaba, and Chiriquí, Panamá). — Salvin and Godman, Biol. Centr.-Am., Aves, ii, 1892, 216, part (Chontales and Los Sábalos, Nicaragua; Angostura, Pacuare, Pejé, San Carlos, Jiménez, La Balsa, and Pozo Azúl de Pirrís, Costa Rica; Chiriquí, Bugaba, and Lion Hill, Panamá). — Richmond, Proc. U. S. Nat. Mus., xvi, 1893, 501 (Rio Escondido, Nicaragua; habits). — Cherrie, Expl. Zool. Merid. Costa Rica, 1893, 43 (Palmár, Lagarto, Boruca, and Buenos Aires, s. w. Costa Rica; habits). — Bangs, Auk, xxiv, 1907, 296 (Boruca, Paso Reál, Pozo del Rio Grande, and Lagarto, s. w. Costa Rica).
[Formicivora] boucardi Sclater and Salvin, Nom. Av. Neotr., 1873, 72, part. — Sharpe, Hand-list, iii, 1901, 26, part.
Formicivora boucardii Lawrence, Ann. Lyc. N. Y., ix, 1868, 108 (Angostura, San José, and Pacuare, Costa Rica). — Frantzius, Journ. für Orn., 1869, 305 (Costa Rica). — Zeledón, Anal. Mus. Nac. Costa Rica, i, 1887, 115 (Pozo Azúl, Pacuare, Jiménez, and La Balsa, Costa Rica).
Formicivora boucardi Cherrie, Anal. Inst. Fis.-Geog. Costa Rica, vi, 1893, 19 (Pozo del Pitál, Costa Rica).
Formicivora quixensis (not Thamnophilus quixensis Cornalia) Lawrence, Ann. Lyc. N. Y., vii, 1862, 325 (Lion Hill Station, Panamá).
Formicivora virgata Lawrence, Ibis, v, April, 1863, 182 (Lion Hill Station, Panamá; coll. G. N. Lawrence); Ann. Lyc. N. Y., viii, 1863, 484 (Lion Hill). — Salvin and Godman, Biol. Centr.-Am., Aves, ii, 1892, 217 (Chontales, Nicaragua; Lion Hill, Panamá).
D[rymophila] virgata Richmond, Auk, xvi, Oct., 1899, 354, in text.
[Formicivora] virgata Sharpe, Hand-list, iii, 1901, 26 (Panamá to Nicaragua).
Formicivora boucardi virgata Carriker, Ann. Carnegie Mus., vi, 1910, 610 (Costa Rica; crit.; habits).

MICRORHOPIAS BOUCARDI CONSOBRINA (Sclater).

ECUADORIAN ANTWREN.

Similar to M. b. virgata, but adult male with rectrices more broadly tipped with white, the adult female with under parts deep chestnut instead of rufous- or tawny-chestnut, the upper parts also slightly darker.

Adult male. — Length (skin), 109; wing, 49.5; tail, 46; culmen, 12.5; tarsus, 16.[13]

Adult female. — Length (skin), 116-121 (118); wing, 48.5-51.5 (50); tail, 45.5-52 (48.7); tarsus, 16.5; middle toe, 10.[14]

Northwestern Colombia (Rio Truando) to western Ecuadór (Babahoyo; Esmeraldas; Balzár Mts.; Sarayacu; Chimbo) and Cayenne.

Formicivora consobrina Sclater, Proc. Zool. Soc. Loud., I860, 279, 294 (Babahoyo, w. Ecuadór; coll. P. L. Sclater); Cat. Am. Birds, 1862, 183 (Babahoyo) ; Cat. Birds Brit. Mus., xv, 1890, 255 (Babahoyo, Esmeraldas, Balzár Mts., and Sarayacu, Ecuadór; Pocune aud Medellin, Antioquía, and Bogotá, Colombia; Cayenne). — Sclater and Salvin, Proc. Zool. Soc. Lond., 1879, 525 (Pocune, Antioquía, Colombia). — Berlepsch and Taczanowski, Proc. Zool. Soc. Lond., 1883, 565 (Chimbo, w. Ecuadór).
[Formicivora] consobrina Sclater and Salvin, Nom. Av. Neotr., 1873, 72. — Sharpe, Hand-list, iii, 1901, 26.
D[rymophila] consobrina Richmond, Auk, xvi, Oct., 1899, 354, in text.
Formicivora quixensis (not Thavinophilus quixensis Cornalia) Cassin, Proc. Acad. Nat. Sci. Phila., 1860, 190 (Rio Truando. n. w. Colombia).
Formicivora boucardi (not of Sclater) Salvin and Godman, Biol. Centr.-Am., Aves, ii, 1892, 216, part (Rio Truando).

MICRORHOPIAS GRISEA ALTICINCTA (Bangs).

SAN MIGUÉL ANTWREN.

Similar to M. g. intermedia[15] of Colombia and Venezuela, but adult male much darker above (deep grayish sepia, purplish slate color, or deep brownish slate instead of hair brown or broccoli brown) and more extensively black beneath, the adult female darker brown above and much more strongly buffy beneath.

Adult male. — Above plain purplish slate color (between slate color and seal brown), deep grayish sepia or deep brownish slate ; wings and tail black; anterior portion of lesser wing-covert area white, the remaining lesser coverts, together with middle coverts, with a small terminal roundish spot of white; greater coverts broadly tipped with white, forming a very conspicuous band across wing; remiges narrowly and indistinctly edged (except basally) with grayish brown, the edgings broader on tertials, where sometimes whitish terminally; three outermost rectrices (on each side) broadly tipped with white, this extending much farther on outer than on inner web, the extent of the white greatest (on both webs) on second rectrix; a broad superciliary stripe of white extending from sides of forehead to sides of nape, where confluent with a white area extending from sides of neck to flanks; loral, suborbital, auricular, and malar regions, chin, throat, chest, breast, abdomen, and under tail-coverts uniform black, the sides and flanks immaculate white outwardly, streaked black and white along exterior margin of the black median area; under wing-coverts black (the under primary coverts white, tipped with black); inner web of remiges broadly edged with grayish white; bill black, paler on tomia; legs and feet grayish black (plumbeous in life?); length (skin), 113-116 (115); wing, 54.5-59 (55.7); tail, 45-49 (46.5); culmen, 14-15 (14.5); tarsus, 20-21.5 (20.3); middle toe, 11-12 (11.5).[16]

Adult female. — Above much as in adult male, but the general color decidedly more brownish (deep broccoli brown on back, etc., more grayish brown on pileum and hindneck), the remiges more distinctly edged with brown; sides of head (including superciliary stripe, which is less sharply defined than in adult male) pale grayish buffy or dull buffy whitish, interrupted by a narrow postocular streak of dusky, the suborbital region with very narrow and indistinct bars of dusky, the auricular region with fine shaft-streaks of whitish; chin and upper throat white, passing into buff on chest, this into paler buff on other lower parts, the under tail-coverts (sometimes flanks also) and center of abdomen nearly white; bill and feet as in adult male, but mandible palo grayish brown (bluish gray in life?); length (skin), 112-116 (114); wing, 50-52.5 (51.5); culmen, 43-45 (43.8); tarsus, 14-14.5 (14.1); middle toe, 11-11.5 (11.2).[17]

Immature male. — Similar to the adult female, but whitish superciliary stripe more distinct, and with throat, chest, and breast intermixed with black.

San Miguel Island, Bay of Panamá.

Drymophila intermedia (not Formicirora intermedia Cabanis) Bangs, Auk, xviii, Jan., 1901. 30 (San Miguél I., Bay of Panamá).
Formicivora alticincta Bangs, Proc. New Engl. Zool. Club, iii. Mar. 31, 1902, 71 (San Miguél I., Bay of Panamá; coll. E. A. and 0. Bangs). — Thayer and Bangs, Bull. Mus. Comp. Zool., xlvi, 1905, 150 (San Miguél I., crit.).


  1. Probably also in the closely related M. quixensis and M. bicolor, which, however, I have not seen.
  2. I am very doubtful whether the group comprising Turdus griseus Boddaert, Formicivora intermedia' Cabanis, and Thamnophilus rufaler Lafresnaye and D'Orbigny should be included in this genus, for apart from the very different style of coloration, these species differ from Microrhopias proper in obsolete instead of conspicuously developed rictal bristles, much longer tarsus, and some other less marked characters.
  3. Turdus griseus Boddaert, Tabl. Pl. Enl., 1783, 39 (based on Le grisin de Cayenne Daubenton, Pl. Enl., pl. 643, fig. 1). — [Motacilla] grisea Gmelin, Syst. Nat., i, pt. 2, 1789, 964. — Thamnophilus griseus Spix, Av. Bras., ii, 1825, 29, part, pl. 41, fig. 1 (Pará). — F[ormicivora] grisea Cabanis, in Wiegm. Archiv für Naturg., 1847, pt. i, 225. — Formicivora grisea Sclater, Proc. Zool. Soc. Lond., 1858, 238; Cat. Birds Brit. Mus., XV, 1890, 249. — Ellipura grisea Burmeister, Syst. Ueb. Th. Bras., iii, 1856, 67. — Drymophila grisea Richmond, Auk, xvi, Oct., 1899, 354, in text. — Formicivora nigricollis Swainson, Zool. Journ., ii, no. vi, July, 1825, 147 (catinga woods of Humildez, Brazil; coll. W. Swainson). — M[yiothera] superciliaris Lichtenstein, Verz. Doubl., 1823, 44 (Cayenne). — Formicivor[a] deluzae Ménétriés, Mém. Acad. Imp. Sci. St. Petersb., ser. 6, etc., i, 1835, 484, pl. 5, fig. 2 (Serra dos Orgâoes, near Rio de Janeiro, Brazil; coll. Acad. St. Petersb.).
  4. Formicivora tobagensis Dalmas, Mem. Soc. Zool. France, xiii, 1900, 141 (Tobago; coll. Count Dalmas). — D[rymophila] grisea tobagensis Ridgway, Proc. Biol. Soc. Wash., xxi, Oct. 20, 1908, 194, in text.
  5. Drymophila grisea margaritensis Ridgway, Proc. Biol. Soc. Wash., xxi, Oct. 20, 1908, 194 (Margarita I., Venezuela; coll. U. S. Nat. Mus.).
  6. F[ormicivora] intermedia Cabanis, in Wiegm. Archiv für Naturg., xiii, Bd. 1, Heft 2, 1847, 225 (Cartagena, Colombia, and Aragua Valley, Venezuela; coll. Berlin Mus.). — Formicivora intermedia Sclater, Cat. Birds Brit. Mus., xv, 1890, 250. — D[rymophila] intermedia Richmond, Auk, xvi, Oct., 1899, 354, in text. — Eriodora intermedia Bangs, Proc. Biol. Soc. Wash., xii, June 3, 1898, 138 (Santa Marta, Colombia).
  7. I have not seen adult females of M. g. tobagensis nor M. g. margaritensis. In addition to the forms mentioned in the key, two others (apparently conspecific) are autoptically unknown to me: Formicivora orenocensis Hellmayr, Bull. Brit. Orn. Club, xiv, Feb. 27, 1904, 54 (Altagracia, Orinoco R., Venezuela; coll. Tring Mus.), and Formicivora cano-fumosus Cherrie, Mus. Brookl. Inst. Arts and Sci., Science Bull., i, no. 16, June 30, 1909, 387 (Las Barrancas, Orinoco R., Venezuela; coll. Mus. Brooklyn Inst.).
  8. Fourteen specimens.
  9. Thirteen specimens.
    Locality. Wing. Tail. Culmen. Tarsus. Middle
    toe.
    males.
    Four adult males from southeastern Mexico 48.9 45.2 14.1 15.5 9
    Eight adult males from Guatemala 48.2 45.8 13.4 15.5 8.9
    Two adult males from Honduras and British Honduras 49.3 46.7 14.3 15.3 9
    Four adult males (M. b. virginata) from Nicaragua 49 43.6 14 15.9 8.9
    Ten adult males (M. b. virginata) from Costa Rica 49.7 44.3 13.7 15.7 9
    Seven adult males (M. b. virginata) from Panamá 49.4 45 13.7 15.6 8.9
    females.
    Six adult females from southeastern Mexico 47.5 44.9 13.3 15.4 8.8
    Six adult females from Guatemala 47.9 46.3 13.2 15.4 8.7
    One adult female from British Honduras 47.5 45 14 15.5 9
    Ten adult females (M. b. virginata) from Costa Rica 48.3 42.5 13.4 15.6 9
    Three adult females from western Panamá (Divala, Chiriqui) 48 43.8 14 16.2 9.5
    One adult female from eastern Panamá (line of railway) 47 42.5 13 16 9.5
  10. A few specimens from Nicaragua and Costa Rica have the flanks slate color, much as in northern examples (M. b. boucardi), but all of the females seen from Costa Rica belong unmistakably to the Panamá form. (I have not seen any females from Nicaragua.) The white mesial streaks showing on the adult male described by Mr. Lawrence (and on which the name virgata was based) are an individual peculiarity, which I do not find repeated in any other specimen examined, even from Panamá. This form is distinctly intermediate in coloration between M. b. boucardi and M. b. consobrina of Colombia and Ecuadór.
  11. Twenty-one specimens.
  12. Fourteen specimens.
  13. One specimen, from Rio Truando, Colombia.
  14. Two specimens.
    Locality. Wing. Tail. Tarsus. Middle
    toe.
    females. One adult female from Rio Truando, Colombia 48.5 45.5 16.5 10 One adult female from Ecuador 51.5 [52?] 16.5 10

    Besides having a longer wing and, apparently, much longer tail than the Rio Truando specimen, that from Ecuadór has the white tips to the rectrices much more extensive. The specimens examined, however, are all imperfect, and a much better series would be necessary to show whether the Colombian and Ecuadorian birds are really different or not.

  15. See p. 77.
  16. Six specimens.
    Locality. Wing. Tail. Culmen. Tarsus. Middle
    toe.
    males.
    Six adult males from San Miguél Island 55.7 46.5 14.5 20.3 11.5
    Six adult males (M. g. intermedia) from Colombia 53.5 48 14.8 20.3 11.5
    Three adult males (M. g. margaritensis) from Margarita I., Venezuela 53.7 47.8 14.3 20 11.3
    Two adult males (M. g. intermedia) from Venezuela (mainland) 54.7 49.5 14 21 11.5
    One adult male (M. g. tobagonsis) from Tobago 59.5 52.5 - 22 12.5
  17. Three specimens.