PERCHING BIRDS. 
indeed being noted for their powers of song. They are less migratory 
than insect-eating birds and some species are with us at all seasons. 
Their abundance, musical gifts, and constant presence render them, 
from the field student’s point of view, highly important members of 
the great class Aves. 
From an economic standpoint the Fringillidz are no less deserving 
of our esteem. Some species are of incalcuable value as destroyers 
of the seeds of noxious weeds. Fifteen hundred seeds have been 
found in the stomach of one Snowflake or Snowbunting, and it has 
been estimated by Professor Beal, of the Biological Survey of the 
United States Department of Agriculture, that during the winter 
season, in the single State of Iowa, where his studies were made, 
Tree Sparrows devour no less than 875 fons of weed seeds, chiefly 
of the ragweed. : 
The Tanagers, (Family Zanagridz) are found only in the New 
World, where they are most numerously represented in the tropics. 
As a family they are remarkable for the brilliancy of their colors; the 
common, but mistaken idea that most tropical birds are brightly clad 
being in no small part due to the abundance of Tanagers and beauty of 
their plumage. 
Only five of the some three hundred and fifty known species reach 
the United States and these are migratory, coming to us in the spring 
and returning to the tropics in the fall. Tanagers, as a rule, are not 
possessed of much vocal ability, our species ranking high in their fam- 
ily as songsters, the notes of many species being far less musical. 
Like most gaily costumed birds the plumages of many Tanagers un- 
dergo striking changes in color with age and season. The male.of our 
Scarlet Tanager, for example, is olive-green with black wing-coverts 
during his first winter, the scarlet plumage not being acquired until the 
following spring. Itis worn, however, only during the nesting season 
after which the less conspicuous olive-green dress is again acquired, 
the wings and tail, however, remaining black. 
Swallows, (Family Hirundinidz) are of world-wide distribution, and 
as might be expected in birds possessing such remarkable powers of 
flight, many of the species have unusually extended ranges. Our Barn 
Swallow, for example, is found throughout North America in summer, 
and in the winter it migrates as far south as southern Brazil. 
Birds of the air, the aerial habits of Swallows are reflected in their 
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