448 REVIEW OF AMERICAN BIRDS. [PART I. 
head, than those from the Rocky Mountains; and among them are 
several with unusually large 
bills, almost as large as that 
of C. elegans, one of which 
(No. 26,438) measures .95 
from forehead, .55 from nostril, 
and 1.05 from gape, which 
generally exceeds the average. 
The other characters, however, 
are essentially those of excubi- 
toroides. In nearly the whole 
series (all autumnal birds) 
there is a decided tinge of reddish on breast and sides, which also 
are obscurely undulated with dusky. 
Specimens from the Mississippi Valley, east of the river, are 
darker, with the white markings less prominent, and with a general 
approximation to the characters of C. ludovicianus. They, are, 
however, usually paler than the California birds. Mexican speci- 
mens are perhaps more like those just referred to, and less typical, 
although some are true and well-marked excubitoroides. One of 
these Mexican skins (No. 13,600) has an unusually slender and 
deeply hooked bill. (See figure above.) 
In this species (?), as in C. ludovicianus, there is so much varia- 
tion in the amount of white on the tail, as well as in the comparative 
length of the feathers, as to unfit these features for specific indica- 
tion, except as a general average. 
This Shrike, in its extreme stage of coloration, differs from Judo- 
vicianus in paler and purer color; the ash of back lighter; the 
under parts brilliant white, not decidedly plumbeous on the sides as 
~ in the other, and without so great a tendency to the usual obsolete 
waved lines (noticed distinctly only in winter or immature birds) ; 
the axillars bluish-white, not plumbeous. The white of wings and 
tail is more extended; the hoary of forehead and whitish of scapu- 
lars more distinct. The bristles at base of bill somewhat involving 
the feathers are black, forming a narrow frontal line, not seen in the 
other. The most striking difference is in the rump and upper tail 
coverts, which are always appreciably and abruptly lighter than 
the back, sometimes white or only faintly glossed with plumbeous ; 
while in typical specimens of /udovicianus these feathers are scarcely 
lighter at all, and generally more or less varied with blackish spots 
at the end. The legs and tail are apparently longer, the latter less 
26438 (7 Sa Af 
