BIRDS OF EASTERN MASSACHUSETTS. 
95 
extremes; I have birds exhibiting every shade of color 
between, but remarkably variable. 
Upon these inconstant characters does the specific value 
of Americana rest ! Very pertinent then are the grave 
doubts expressed by ornithologists as to its validity as a 
species. Xhe following is an accurate description of the 
specific characters, with the more important synonymes, 
and a table of comparative measurements. 
Troglodytes aedon, Vieill. — House Wren. 
Troglodytes aedon. 
a it 
t( u 
(( u 
4 ( (4 
U U 
U li 
Sylvia domestica. 
Troglodytes fulvus. 
U (4 
Troglodytes Americanus. 
U 44 
44 44 
ViELLOT, Ois. Am. Sept. II. 1807, 32; PI. 
evil. — Ib. Nouv. Diet. XXXIV. 1819, 506. 
Bonap., Obs. Wilson, 1825, No. 136. 
Eich., F. Bor. Am. II. 1831, 316. 
Aud., Orn. Biog. I. 1831, 427: V. 1839; PI. 
LXXXIII. — Ib. Syn. 1839, 75 . —-Ib.. B irds 
Am. II. 1841, 125; PI. VIII. 
Baird, Birds N. Am. 1858, 367. 
Samuels, Orn. and Ool. of N. Eng. 1867,196. 
CouES, Proc. Essex Inst. V. 1867, 278. 
Wilson, Am. Orn. I. 1808, 129; PI. VIII. 
Nuttall, Man. I. 1832, 422. 
Kick., List, 1837. 
Aud., Orn. Biog. II. 1834, 452: V. 1839, 469, 
PI. 179. — Ib. Birds Am. II. 1841, 123; PI. 
119. — Ib. Syn. 1839, 75. 
Baird, Birds N. Am. 1858, 368. 
CouES, Proc. Essex Inst. V. 1867, 278. 
Sp. Ch. — Bill extremely variable in size, dark brown, 
paler at the base of the lower mandible. Upper parts dark 
brown, becoming more rufous on the rump and upper tail- 
coverts ; middle of back and upper tail-coverts faintly barred 
transversely with irregular lines of darker. The brown of 
the back is exceedingly changeable ; when it becomes light- 
colored, these bars are almost, if not quite, obsolete ; wings 
distinctly and more regularly barred transversely with 
black ; tail reddish brown, irregularly but distinctly barred 
transversely with black, — sometimes this black has a lighter 
edging j under parts dirty white, becoming pale brown on 
