10 ROCKY-MOUNTAIN ANTCATCHER. 
opened, a very offensive odour is diffused, from the remains of half- 
digested ants and other insects, contained in the stomach. 
The plumage of the Antcatchers very probably undergoes con¬ 
siderable changes in colour. The size of the sexes is different, 
the female being much larger than the male. Such variations 
may have induced naturalists to consider many as species, that 
really do not exist, as such, in nature. 
The nest of these birds is hemispherical, varying in magnitude 
according to the size of the species, composed of dried grass, 
rudely interwoven; it is fixed to small trees, or attached by each 
side to a branch, at the distance of two or three feet from the 
ground. The eggs are nearly round, and three or four in number. 
The discovery of any species of this genus in the old world is 
quite recent, and it had previously been believed that the genus 
was peculiar to South America; and though the existence of ant- 
destroying birds was suspected in other tropical regions, they were 
supposed 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 slen¬ 
der, 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 
