These birds were found in all the wooded sections of that region, where they frequented the tops of tall trees. Their song, he states, in its opening, is like that of the Black-Poll, with a terminal warble similar to that of the Redstart, but given with less energy. Dendroica cærulescens, BAIRD. BLACK-THROATED BLUE WARBLER. _Motacilla canadensis_, LINN. Syst. Nat. I, 1766, 336 (not p. 334, which is _D. coronata_). _Sylvia canadensis_, LATH.; WILSON.—AUD. Orn. Biog. II, pl. cxlviii, clv.—SALLÉ, P. Z. S. 1857, 231 (St. Domingo). _Sylvicola canadensis_, SWAINS.; JARD.; BON.; AUD. Birds Am. II, pl. xcv. _Rhimanphus can._ CAB. _Dendroica canadensis_, BAIRD, Birds N. Am. 1858, 271.—IB. P. Z. S. 1861, 70 (Jamaica).—GUNDL. Cab. Jour. 1861, 326 (Cuba; very common).—SAMUELS, 224. _Motacilla cærulescens_, GM. S. Nat. I, 1788, 960. _Sylvia cær._ LATH.; VIEILL. II, pl. lxxx.—D’ORB. Sagra’s Cuba, Ois. 1840, 63, pl. ix, figs. 1, 2. _Dendroica cær._ BAIRD, Rev. Am. B. 1864, 186. _Sylvia pusilla_, WILS. V, pl. xliii, fig. 3 (Juv.). _Sylvia leucoptera_, WILS. _Sylvia palustris_, STEPH. _Sylvia macropus_, VIEILLOT. _Sylvia sphagnosa_, BON.; NUTTALL; AUD. _Sylvicola pannosa_, GOSSE, Birds Jam. 1847, 162 (female).—IB. Illust. no. 37. SP. CHAR. Above uniform continuous grayish-blue, including the outer edges of the quill and tail-feathers. A narrow frontal line, the entire sides of head and neck, chin and throat, lustrous black; this color extending in a broad lateral stripe to the tail. Rest of under parts, including the axillary region, white. Wings and tail black above, the former with a conspicuous white patch formed by the bases of all the primaries (except the first); the inner webs of the secondaries and tertials with similar patches towards the base and along the inner margin. All the tail-feathers, except the innermost, with a white patch on the inner web near the end. Length, 5.50; wing, 2.60; tail, 2.25. _Female_, olive-green above and dull yellow beneath. Sides of head dusky olive, the eyelids and a superciliary stripe whitish. Traces of the white patches at the base of the primaries and of the tail. HAB. Eastern Province of United States; Jamaica, Cuba, and St. Domingo in winter; very abundant; Bahamas (BRYANT). Not recorded from Mexico or Central America. The white patch at the base of the primary, together with the total absence of outer markings on the wings, is peculiar to this species, and is found in both sexes. The female is more different from the male than that of any other species. The plumage of the male in autumn is similar to the spring dress, but the back and wings are washed with greenish, and the black of the throat variegated with white edges to the feathers. A younger male (788, October 10, Carlisle, Penn.) differs in having the black appearing in patches, the throat being mostly white; there is also a narrow white superciliary stripe.