HABITS. A single specimen is said to have been taken near San Antonio, Texas, by Dr. Heermann. It is thought to be probably a bird belonging to the fauna of Arizona and New Mexico, and is given hypothetically by Dr. Cooper among the birds of California. In its appearance it resembles _D. virens_, _D. townsendii_, and _D. occidentalis_. It was originally described by Salvin from a single specimen obtained in Guatemala. Another pair was afterward obtained by Mr. Salvin on the highest point of the road between Salama and Tactic. In regard to its habits, nothing is on record. Dendroica virens, BAIRD. BLACK-THROATED GREEN WARBLER. _Motacilla virens_, GMELIN, Syst. Nat. I, 1788, 985. _Sylvia virens_, LATH.; VIEILLOT; WILS. II; NUTT.; BON.; AUD. Orn. Biog. IV, pl. cccxcix.—GÄTKE, Naumannia, 1858, 423 (Heligoland, Europe, an original description). _Sylvicola virens_, SW.; AUD. Birds Am. II, pl. lxxxiv.—REINHARDT, Vid. Med. for 1853, 1854, 72, 81 (Greenland). _Rhimanphus virens_, CAB. Mus. Hein. Jour. III, 1855, 474 (Cuba; winter).—SCLATER, P. Z. S. 1856, 291 (Cordova). _Dendroica virens_, BAIRD, Birds N. Am. 1858, 267; Rev. 182.—SCLATER & SALVIN, Ibis, 1859, 1 (Guatemala).—SCLATER, P. Z. S. 1859, 363 (Oaxaca?); 373 (Xalapa); Ibis, 1865, 89.—LAWRENCE, Ann. N. Y. Lyc. VII, 1861, 293 (Panama).—GUNDL. Cab. Jour. 1861, 326 (Cuba).—DRESSER, Ibis, 1865, 232.—SAMUELS, 222. _Mniotilta virens_, REINHARDT, Ibis, III, 1861, 5 (Julianhaab, Greenland). SP. CHAR. Male. Upper parts, exclusive of wing and tail, clear yellow olive-green; the feathers of the back with hidden streaks of black. Forehead and sides of head and neck, including a superciliary stripe, bright yellow. A dusky olive line from the bill through the eye, and another below it. Chin, throat, and forepart of the breast, extending some distance along on the sides, continuous black; rest of under parts white, tinged with yellow on the breast and flanks. Wings and tail-feathers dark brown, edged with bluish-gray; two white bands on the wing; the greater part of the three outer tail-feathers white. _Female_ similar, but duller; the throat yellow; the black of breast much concealed by white edges; the sides streaked with black. Length, 5 inches; wing, 2.58; tail, 2.30. HAB. Eastern Province of United States; Greenland; Heligoland, Europe; south to Panama R. R. In Mexico, Xalapa, Cordova, and Oaxaca? Cuba alone in West Indies. Mexico (everywhere in winter, SUMICHRAST). The autumnal male has the black of throat and breast obscured by whitish tips. Females are yellowish-white beneath, tinged with grayish towards the tail. As shown in the generic chapter, _D. virens_ is the type of a section of olivaceous Warblers with black chin and throat. The following more elaborate diagnoses of the group may facilitate its study, the species being quite closely related:—