ROCKY MOUNTAIN ANTCATCHER. 169 
be the fact in the case of the ant-eating quadrupeds. This 
opinion was founded on the admitted axiom that Nature 
always varies her groups in remote tropical regions having no 
communication with each other. The reverse, however, is the 
fact in the case of the ant-catching birds, as we find perfect 
analogies between the species residing in those distant parts 
of the globe, even throughout the different sections into which 
the genus may be divided. 
The Rocky Mountain antcatcher is six inches long. The 
bill, measured from the corner of the mouth, is more than one 
inch in length, being slightly curved almost from the base ; 
it is very slender, being nearly two-eighths of an inch in dia- 
meter at the base, and only the sixteenth of an inch in the 
middle, whence it continues to diminish to the tip; and is of 
a dark horn colour, paler beneath. The feet are dusky, and 
the length of the tarsus is seven-eighths of aninch. The irides 
are dark brown; the whole plumage above is of a dusky 
brownish, slightly undulated with pale, tinted with dull fer- 
ruginous on the top of the head and superior portions of the 
back. ‘The sides of the head are dull whitish, with a broad 
brown line passing through the eye to the commencement, of 
the neck. The chin, throat, and breast are whitish, each 
feather being marked by a longitudinal line of light brown. 
The belly is white, and the flanks are slightly tinged with 
ferruginous. ‘The primaries are entirely destitute of undula- 
tions or spots ; the tail-coverts are pale, each with four or five 
fuscous bands ; the inferior tail-coverts are white, each being 
bifasciate with blackish brown. ‘The tail is nearly two inches 
long, rounded, broadly tipped with ferruginous yellow, and 
having a narrow black band before the tip: the remaining 
part of the tail is of the same colour with the wings, and is 
obsoletely banded, these bands being more distinct on the two 
middle feathers, which are destitute of the black and yellowish 
termination ; the exterior feather is dusky at tip, marked by 
four yellowish white spots on the exterior, and by two larger 
ones on the inner web. 
