102 
MYIOTHERA OBSOLETA. 
to be generically distinct from those of the corresponding 
parts of America, as was known to 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 diameter 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 an inch. The 
irides are dark brown; the whole plumage above is of 
a dusl^v-brownish, slightly undulated with pale, tinted 
with dull ferruginous 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 
w r ith ferruginous. The primaries are entirely destitute 
of undulations 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 
