2 74 
Dwight, The Sharp-tailed Sparrows. 
r Auk 
L oct. 
the former and the bright colors of the latter, being a pale grayish 
looking bird, and the edgings of the back feathers are ashy or 
pearl-gray, according to season, instead of pure white, as in nelsom. 
The accompanying plate is intended to show these differences, and 
on it are figured the type of subvirgatus (No. 1261 $ adult, Hills- 
borough, New Brunswick, July 19, 1886, J. Dwight, Jr.), and a 
breeding male nelsom taken by Dr. Louis B. Bishop in 1 owner 
Co., North Dakota, July 5, 1895 (L. B. B. No. 2071). It seems 
preferable to thus compare two breeding males rather than figure 
the type of nelsoni which, taken in the autumn, is very possibly a 
migrant. The coloring is most excellent save in the tarsus and 
foot of nelsoni , which should be of a purplish flesh color. The 
bills do not show the differences in size that usually are obvious. 
In order to bring out as definitely as possible the points of 
difference (appreciable at any season in all birds, save those in 
first plumage) between these allied races I will present them in 
parallel columns : 
caudacutus. 
nelsoni. 
subvirgatus. 
Lateral crown stripes. 
Deep brown. 
Deep, rich brown. 
Paler, greenish brown. 
Nape and back. 
Browns prevail. 
Browns prevail. 
Grays prevail. 
m 
Outer edgings of back 
feathers. 
Ashy or buffy. 
White and conspicuous. 
Ashy or pearl-gray and 
obscure. 
Edgings of secondaries 
and tertiaries. 
Rusty. 
Bright, rusty buff. 
Paler. 
Breast and sides of 
head. 
Buffy and ochraceous 
tints intense. 
Buffy and ochraceous 
tints more intense. 
Tints pale. 
Breast and flank 
streaks. 
Distinct black and 
broad. 
Obscure, or suffused 
and narrow. 
Obscure, or, suffused 
and medium width. 
Abdomen. 
Clear white. 
Clear white. 
Dingy white. 
Bill. 
Large and long. 
Small and short. 
Medium. 
Measurements. 
Largest size. 
Smallest size. 
Medium size. 
Typical birds are easily recognized when birds of like season 
are compared, but difficulties arise in determining certain fall 
migrants or winter birds (of which there are a large number in 
collections) that show intergradation between nelsoni and subvir- 
gatus. They are taken on the Atlantic coast at various points 
