Notes on the Plumage of North American Sparrows 
SECOND PAPER 
By FRANK M. CHAPMAN 
(See frontispiece) 
Song Sparrow (Fig. 2). The fusing of the spots on the central breast-feathers 
- to make a larger spot or blotch and the pronounced maxillary stripes are the chief 
distinguishing marks of the eastern Song Sparrow, as well as of practically all 
the races of Song Sparrow; add to these certain characteristics of voice and 
manner, and a disposition which usually permits examination at close range, 
and we have a bird which is generally identified without difficulty. 
The sexes are alike, and in view of the exceptional variations shown by this 
species west of the Rockies, the color of our eastern bird is notably uniform. 
It is a fact that the country east of the Rockies is in itself comparatively uniform, 
but nevertheless there are in it areas inhabited by Song Sparrows the climate of 
which differs more widely than that of regions in the West, each of which has a 
different race of Song Sparrow. 
We have, it is true, a slightly grayer form (MM. m. juddt) in North Dakota, 
and specimens resembling this bird are not infrequently found in the Atlantic 
coast states; but, on the whole, our bird shows but little individual variation 
The nestling has the wings and tail like those of the adult, but the body plu- 
mage is softer, the streaks are less sharply defined, the breast blotch is wanting, 
and the plumage is more or less suffused with yellowish buff. It is in this costume 
that the young birds sing the low, indeterminate, rambling song so unlike the lay 
of the adult. 
As Dr. Dwight has shown, in the paper before referred to, this plumage 
may be worn for several months, the molt into the winter plumage occurring from 
August to October. This molt includes all the body feathers, the tail, the tertials 
and wing-coverts, usually the primaries and rarely the secondaries. 
The adult, as is customary, passes from the breeding into winter plumage 
by a complete molt, and is then indistinguishable from young birds in winter 
plumage. Winter birds, aside from differences due to wear, have the breast and 
sides more strongly washed with brownish than do summer specimens. There 
appears to be no molt in the spring, and the difference between sleek winter speci- 
mens and much-bedraggled midsummer ones is due to wear. 
The Song Sparrow is the most plastic of North American birds, or, in other 
words, it is so readily affected in size and color by the climatic conditions under 
which it lives that, given some slight change in the climate of a region, we 
expect to find it reflected in the Song Sparrow of that region. Broadly speaking, 
the general colors of Song Sparrows are related to the rainfall, while their size 
is related to latitude. Thus, the Song Sparrows of arid regions are pale, while the 
Song Sparrows of humid regions are dark. Compare, for example, the figure 
(72) 
