PIED, OR YAURELL’s WAGTAIL. 197 
The principal and most quickly caught dis- 
tinctions between the two birds in question, are 
the greater breadth in the bill of M. Yarrellii, 
when seen from above, (as seen in the cut at 
conclusion of description,) the deep black colour 
of all the upper parts in the plumage of the 
summer, and the different form of the black on 
the throat and breast. In this species, which 
assumes a gray tint on the back during winter, 
the tint is nearly the blackish gray of Syme, 
mixed with a little brown, while, in the Conti- 
nental bird, it is of a much clearer shade, and 
resembles closely dark bluish gray of the same 
nomenclature. 
In the plumage of the male in summer, the 
upper parts, tail, except the two outer feathers, 
on each side the throat and breast, are deep 
black, on the rump there is occasionally a tinge 
of gray. In winter the black throat is lost, and 
that colour on the breast is restricted to the form 
of a crescent ; above, the centre of the back 
becomes deep blackish gray, and specimens fre- 
quently occur where the black of the former state 
continues intermixed. The secondaries, greater 
and lesser coverts, become more broadly edged 
with white, and the feathers of the rump obtain 
narrow edgings of the same hue. 
M. Alba. 
M. Yarrellii. 
