Type.—Ps[arocolius] gularis Wagler, Isis, 1829, p. 754 (type locality, Tehuantepec, Oaxaca).

Diagnosis.—Medium-sized Icteridæ with short, heavy bill; a prominent knoblike projection on the posterior median portion of the palate, broad and somewhat flattened in general form, with abrupt sides, truncated in front, sometimes with a tooth or notch at the anterior ventral angle, about 2 millimeters broad and from 1.2 to 1.5 millimeters high in front; depth of culmen at base nearly equal to one-half length of culmen (varying from slightly more to slightly less); tarsus slightly longer than culmen from base; middle toe with claw equal to two-thirds, or slightly more, of length of tarsus.

One species in which three subspecies have been described is at present known to belong in this genus. These will stand as follows:

At present there is no information on the feeding habits of these orioles available but it seems certain that they will show some striking peculiarity in choice of food or in manner of securing and handling it when the life history of the species is better known.

In conclusion I desire to give a brief summary of the condition of the palate in other Icteridæ where comment is necessary. In Euphagus carolinus and E. cyanocephalus there is a slight elongate ridge of low elevation, rounded posteriorly more acute in front, and not projecting as far as the level of the tomia. This raised line is slightly more pronounced in E. carolinus than in E. cyanocephalus in spite of the fact that the latter has a heavier, stronger bill. The species known as Ptiloxena atroviolacea has an elongate, narrow, slightly elevated ridge on the posterior portion of the palate, rounded behind and more or less acute in front, but with too low an elevation to be considered a highly specialized structure. Sumichrast’s Blackbird (Dives dives) has a palatal structure somewhat resembling that of the genus Holoquiscalus save that the entire ridge is shorter.

With regard to others, Tangavius æneus has a slight ridge, that becomes stronger behind, extending for two-thirds the length of the palate. A similar ridge in Molothrus badius is less developed at its anterior end than in the preceding genus. In Molothrus fringillarius (one specimen only examined) this ridge is still less in development. In Molothrus ater, the cutting edges of the tomia do not extend below the level of the palate, and there is a rounded swelling behind the center; in Molothrus atronitens only a very slight ridge is present, and finally in M. rufo-axillaris there is no peculiarity worthy of mention. Nesopsar nigerrimus shows a well marked rounded ridge on the posterior part of the palate that merges into the anterior surface without becoming produced as an angle. Xanthopsar imthurmi shows a slightly developed posterior ridge, while in Agelaius phœniceus (including gubernator) there is a very faint swelling at the posterior end of the palate, that becomes much more pronounced in A. tricolor. Agelaius thilius and A. icterocephalus show a faintly raised median line, that in the latter species is broadened and rounded posteriorly. Amblyrhamphus holosericeus has a long, low, keeled median ridge, and in the three species of Sturnella there is an elongate keel, that is rounded behind and acute in front. In Curæus aterrimus the palate is on a level with the edge of the tomia, and has a low rounded bulge on its posterior surface. Trupialis militaris and T. falklandicus have a slight rounded posterior ridge, that is absent in T. bellicosa and T. defillipi, and finally in Gymnomystax melanicterus there is a low, narrow, keeled ridge on the posterior part of the palate, that merges gradually into the surrounding level in front. None of the other species seen present any marked peculiarities.