SYLVICOLIDZ, WARBLERS.—GEN. 35. 101 
often obsolete on the crown; below more or less completely tinged with 
pale greenish-yellow, the streaks very obscure and sometimes altogether 
wanting; under tail coverts usually pure white; a yellowish superciliary 
line ; wing-bars tinged with the same color. When the streaks on the sides 
are obsolete, the species bears an extraordinary resemblance to young 
castanea, which see. One of the larger species; 53-53, wing 23-3, tail 
2-24. Eastern North America, very abundant; a late migrant; when the 
black-polls appear in force, the collecting season is about over! Wiuxs., iv, 
20M ple 30; f..3); vi, LOL, plo54, f. 3; Nurr., i, 3833 Aup., ii, 28, pl. 
eee OU namepette Meo Sy ep cali yiaete crise tek, a ays ois en eR DAS 
Bay-breasted Warbler. Autumnal Warbler. ¢ in spring: back thickly 
streaked with black and grayish-olive; forehead and sides of head black 
enclosing a large deep chestnut patch; a duller chestnut (exactly like a blue- 
bird’s breast) occupies the whole chin and throat and thence extends, more 
or less interrupted, along the entire sides of the body; rest of under parts 
ochrey or buffy whitish; a similar buffy area behind the ears; wing-bars and 
tail-spots ordinary; bill and feet blackish. The 9 in spring is more oliva- 
ceous than the male, with the markings less pronounced ; but always shows 
evident chestnut coloration; and probably traces of it persist in all adult 
birds in the fall. The young, however, so closely resemble young striata, 
that it is sometimes impossible to distinguish them with certainty. The 
upper parts, in fact, are of precisely the same greenish-olive, with black 
streaks; but there is generally a difference below —castanea being there 
tinged with buffy or ochrey, instead of the clearer pale yellowish of striata; 
this shade is particularly observable on the belly, flanks and under tail 
coverts, just where striata is whitest ; and moreoyer, castanea is usually not 
streaked on the sides at all. Mature spring birds vary interminably in the 
extent and intensity of the chestnut. Size of striata. Eastern United 
States, abundant. Sylvia autumnalis. Wits., iii, 65, pl. 23; Nurr., i, 
390; Aup., Orn. Biog., i, 447, pl. 83 (young). WHLS,, ii, 97, pl. 14, f. 
AP MNUO igi Oo2 5 AUD.) 1, pl. 805 BD.,.206. 5 ans . Ste SCASTANEA. 
Chestnut-sided Warbler. @ in spring: back streaked with black and 
pale yellow (sometimes ashy or whitish) ; whole crown pure yellow immedi- 
ately bordered with white, then enclosed with 
black; sides of head and neck and whole under 
parts pure white, former with an irregular black 
crescent before the eye, one horn extending back- 
ward over the eye to border the yellow crown and 
be dissipated on the sides of the nape, the other 
reaching downward and backward to connect with 
a chain of pure chestnut streaks that run the whole Frc. 43. Chestnut-sided Warbler. 
length of the body, the under eyelid and auriculars being left white; wing- 
bands generally fused into one large patch, and, like the edging of the 
inner secondaries, much tinged with yellow; tail-spots white, as usual; 
bill blackish, feet brown. 9 in spring, quite similar; colors less pure ; 
