RIO GRANDE YELLOW-THROAT 263 



Nesting Date. Comondu, Lower California, March 25 (Bryant). 

 BIOGRAPHICAL REFERENCES 



(i) W. L. BEYANT, A Catalogue of the Birds of Lower Calif., Proc. 

 Calif. Acad. Sci. 2nd Ser. II, 1889, 20. (2) Ibid., 310. (3) WM. BREWSTER, 

 Birds of the Cape Region of Lower California, Bull. Mus. Comp. Zool., XLI, 

 1902, 187. 



Genus CHAALETHLYPIS Ridgway 



Chamathlypis appears to be a connectant between Icteria and Geo- 

 thlypis. In general appearance it suggests Geothlypis but the bill is 

 stouter and strongly, decurved, in fact, chat-like ; the wing is even more 

 rounded than in Geothlypis but the tail is decidedly longer than in that 

 genus. The two known species inhabit Central America and Mexico 

 and one of them reaches our limits on the Lower Rio Grande. 



Rio GRANDE YELLOW-THROAT 



CHAALETHLYPIS POLIOCEPHALA POLIOCEPHALA (Baird! Plate XVII 



Distinguishing Characters. The heavy, curved bill, slaty head and black 

 lores, in connection with the yellow throat, distinguish this species from any 

 other of our Warblers. Length (skin), 5.25; wing, 2.15; tail, 2.35; bill, .50. 



Adult 3, Spring. Crown slaty with a slight olive wash, lores black, this 

 color extending below the eye; a white mark on eye-ring above and below 

 the eye; back, wings and tail olive-green without white markings, bend of 

 wing yellow; throat and breast bright yellow becoming paler on the belly and 

 brownish on the flanks. 



Adult <$, Fall. "Similar to the Spring and Summer plumage, but plumage 

 softer, more blended ; back, etc., more buffy olive or bright olive-brown ; feathers 

 of pileum (at least the occiput) tipped with brown, and flanks more decidedly 

 buffy." (Ridgw.) 



Young <$, Fall. "Similar in general to the adult plumage, but duller, the 

 pileum concolor with back, or nearly so, and lores dull brownish gray or dusky, 

 not distinctly different from color of pileum." (Ridgw.) 



Adult and young ?. Resemble young <$ in Fall. 



Nestling. Not seen. 



General Distribution. Northeastern Mexico north to Browns- 

 ville, Texas. 



The Bird and its Haunts. Nothing appears to have been written 

 concerning the habits of this species. 



Genus ICTERIA Vieillot 



Icteria virens, the single species in this genus, is our largest mem- 

 ber of the family Mniotiltidae. In addition to size it is further distin- 



