The aspect of this animal is far more fierce and formidable than either the common red wolf, or the prairie wolf, and is of a more robust form. The length of the ears and tail distinguish it at once from the former, and its greatly superior size, besides the minor characters of colour, &c., separate it from the prairie wolf. As the black wolf (C. lycaon,) is described to be of a deep and uniform black colour, and his physiognomy is represented to be nearly the same as that of the common wolf, it is beyond a doubt different from this species. It has the mane of the _mexicanus_. It diffuses a strong and disagreeable odour, which scented the clothing of Messrs. Peale and Dougherty, who transported the animal several miles from where they killed it to the cantonment. 1. _Sylvia celatus._--_Above_ dull greenish-olive; _rump_ and _tail coverts_ purer greenish-olive; _primaries_ and _tail feathers_ blackish-brown, olive-green on the exterior margins, and white on the interior margin; _head_ very slightly and inconspicuously crested; _crest_ with the feathers orange at base; _bill_ horn colour, slender, base of the inferior mandible whitish beneath; _beneath_ olivaceous yellow; _inferior tail coverts_ pure yellow; _legs_ dusky. Length 5-1/4 inches. Shot at Engineer Cantonment early in May. This bird is distinguished by the colour of the feathers on the crown of the head, which are of a fulvous colour, tipped with the same colour as that of the neck and back, so that the fulvous colour does not appear at first sight. The wings are destitute of any white band, and the margins of the six exterior primaries are much paler than those of the others. We cannot find any description of this bird; it seems, however, to approach nearest to the S. _leucogastra_, Steph., Nashville warbler of Wilson; but in our specimen the belly is not white, neither does Wilson's description of the colour of the head of his Nashville warbler agree at all with that of our bird. 2. _Sylvia bifasciata._--Above bluish; all beneath white; _head_ highly varied with darker; between the eyes and bill blackish; _bill_ black; _interscapulars_ lineate with blackish; _wings_ blackish; _shoulders_ bluish; _wing coverts_ with two white bands; _primaries_ margined with white on the inner side, and with plumbeous on the exterior side; _tail_ black; _feathers_ blackish, white on the inner margin, and plumbeous on the exterior margin; and, excepting the two middle ones, with a white spot on the inner side, near the tip; _flanks_ spotted with plumbeous; _feet_ black. Length rather more than 4-3/4 inches. Shot in May, near Engineer Cantonment. This species seems to approach very closely to S. cærulea. _Genus Limosa_, CUV.