388 U. S P R. R. EXP. AND SURVEYS-ZOOLOGY-GENERAL REPORT. 
In the group, as defined above, are embraced several genera of modern systematists. Thus 
the true black-capped American titmice are placed under Poecile of Kaup, where possibly they 
belong. The species may be arranged as follows : 
A. Head and neck above and below entirely black ; their sides white. ( Poecile .) 
Outer tail feathers and the tertiaries conspicuously edged with white. Outer edges of 
greater wing coverts also nearly white. 
Largest. Wing, 2.10 inches; tail much rounded, or even graduated, exceeding 3.00, 
or longer than wings. P. septentrionalis. 
Wing and tail about 2.50 inches, and nearly equal. Tail nearly even. Body 
beneath white, tinged on the sides with brownish yellow. P. atricapillus. 
Size and shape much like the last. Tail more rounded. Beneath pale yellowish 
rufous brown, lighter only along the median line. P. occidentalis. 
Outer tail feathers and the tertiaries pale grayish, not white. Greater wing coverts 
without paler edges. Tail nearly even, shorter than the wing. 
Wing, about 2.60 inches; tail, 2.45. Beneath plumbeous; similar to the back, 
only paler. P. meridionalis. 
Smaller. Beneath white, faintly tinged with reddish brown, conspicuously 
different from the back. P. carolinensis. 
B. Crown and throat black, with white frontal and superciliary stripe. 
Above plumbeous ; beneath white. P. montanus. 
C. Throat sooty brownish ; sides of body bright reddish brown. 
Back and wing coverts chestnut brown ; crown not very different from the 
throat... P. rufescens. 
Back grayish olive brown. Crown similar. P. Jmdsonius. 
Comparative measurements of species. 
Catal. 
No. 
Species. 
Locality. 
Sex. 
Length. 
Stretch 
of wings. 
Wing. 
Tail. 
Tarsus. 
Middle 
toe. 
Its claw 
alone. 
Bill 
above. 
Along 
gape 
Specimen 
measured. 
3704 
5.40 
2 72 
2.96 
0.68 
0.58 
0.18 
0.34 
0.40 
6766 
5.80 
2.52 
3.00 
0.40 
0.42 
Skin*.... 
8627 
5.30 
2.64 
2.86 
0.64 
0.60 
0.22 
0.38 
0.46 
5.75 
8.25 
2.75 
Fresh.... 
8493 
O 
5.32 
2 62 
2.98 
0.64 
0.58 
0.18 
0.34 
0.40 
Skin. 
830 
o 
4.80 
2.50 
2.50 
0.62 
0.55 
0.18 
0.36 
0.40 
Skin. 
do. 
V 
5.00 
7.75 
2.50 
Fresh.... 
803 
4.74 
2.50 
2.44 
0.60 
0.56 
0.20 
0.36 
0.42 
Skin. 
do. 
4 91 
7.75 
2.41 
Fresh.... 
6762 
5.00 
2.46 
2.50 
0.64 
0.56 
0.20 
0.36 
0.42 
Skin. 
4.50 
7.50 
Fresh.... 
5.00 
2.42 
2.52 
0.66 
0.60 
0.20 
0.36 
0.44 
Skin. 
5.00 
7.50 
Fresh ... 
10203 
5.00 
2.60 
2.54 
0.68 
0.56 
0.18 
0.36 
0.42 
Skin. 
706 
A 
4 60 
2.50 
2.50 
0.60 
0.54 
0.20 
0.32 
0.38 
Skin. 
O 
4.62 
7.00 
Fresh.... 
5643 
o 
5.50 
2.90 
2.90 
0.78 
0.58 
0.20 
0.44 
0.50 
Skin. 
3894 
V 
5.00 
2.58 
2.44 
0 64 
0.64 
0.21 
0.42 
0.42 
Skin. 
962 
9 
4.80 
2.70 
2.58 
0.72 
0.60 
0.22 
0.42 
0,44 
Skin. 
5.00 
8.00 
Fresh.... 
6786 
4.46 
2.36 
2.16 
0.64 
0.60 
0.18 
0.35 
0.40 
Skin.... 
4 75 
7.50 
Fresh.... 
6784 
4.44 
2.42 
2.30 
0.64 
0.56 
0.18 
0.40 
0.44 
Skin. 
2926 
Parus hudsonicus. 
Canada.'’. 
5.14 
2.40 
2.66 
0.70 
0.55 
0.19 
0.38 
0.44 
Skill. 
* Very poor specimen. 
