BIRDS—TUEDIDAE-SIALIA. 
221 
probability, is the same with that considered as peculiar to North America under the name of 
S. oenanthoides. The differences are, as far as indicated, merely those of size, the skin described 
by Mr. Cassin being G.50 inches long ; the wing 4.12 ; the tail 3.00 ; the tarsus 1.25. This is, 
however, by no means an unusual discrepancy in birds of remote localities, and until better 
characters can be assigned there would seem little propriety in making two species. 
The Saxicola oenanthe of Europe is recognized as a regular inhabitant of Greenland, and 
those found on the main land of America in all probability reach it from that country. 
List of specimens. 
Locality. 
Whence obtained. 
Len th 
Wing. 
Tail. 
Tarsus. 
Middle 
toe. 
Its claw 
alone. 
Bill 
above. 
Along 
gape. 
Europe_ 
J. Cassin... 
6. 00 
3. 65 
2.50 
1. 05 
0. 75 
0. 20 
0. 60 
0.80 
SIALIA, Swainson. 
Sialia, Swainson, Zool. Jour. Ill, Sept. 1827, 173. (S. wilsonii.) 
Ch. —Bill short, stout, broader than high at the base, then compressed ; slightly notched at tip. Rictus with short 
bristles. Tarsi not longer than the middle toe. Claws considerably curved. Wings much longer than the tail ; the first 
primary spurious ; not one-fourth the longest. Tail moderate ; slightly forked. 
The species of this genus are all well marked, and adult males are easily distinguishable. In 
all, blue forms a prominent feature. 
Above uniform dark blue ; beneath brownish red. Abdomen and crissum white.... sialis. 
General color dark blue above and below ; crissum whitish. A broad patch on the 
scapular region (on either side) and on the sides of the breast, brownish red ...mexicana. 
Everywhere greenish blue, becoming whitish on the abdomen and crissum. arctica. 
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. 
1289 
Sialia sialis. 
<? 
6.16 
3.96 
2.88 
0.80 
0 80 
0.22 
0.44 
0.70 
do. 
6.75 
12.50 
4.08 
1283 
O 
6.22 
3.78 
2.72 
o.to 
0.82 
0.21 
0.50 
0.76 
do. 
6.50 
12.00 
3,75 
3907 
6.44 
4.22 
2.80 
0.80 
0.76 
0.22 
0.46 
0.70 
3908 
9 
6.40 
3.40 
2 66 
0.76 
0 78 
0.26 
0.40 
0 70 
3706 
Sialia macroptera, (Baird) .. 
Salt Lake City... 
7.16 
4.78 
3.18 
0.86 
0.82 
0.18 
0.50 
0.80 
7604 
Sialia arctica. 
Mimbres to Ilio 
3 
6.28 
4.46 
3.04 
0.87 
0.76 
0.22 
0.53 
0.76 
Grande. 
8890 
9 
6.80 
4 26 
3.50 
0.78 
0.78 
0 r 2 
0.50 
0.74 
do. 
7.00 
13.25 
4.50 
Fresh ... 
* Legs broken ; poor specimen. 
