BIKDS. 207 



Early in August tbe old birds commence to gradually disappear, aud by the middle of the 

 moutli are seen only occasionally, although on the 18th of August they have been noted on Saint 

 Lawrence Island. Tbe young remain longer aud are found in scattered parties all about the 

 settlements and uati\e houses in the same localities favored by the common Water Wagtail, which 

 occurs sparingly along the coast at this season. The Yellow Wagtail trips daintily along the 

 grassy margins of the muddy spots, its vibrating tail and slender form distinguishing it among the 

 motley crowd of Savanna Sparrows, Lai)land Longspurs, and common Wagtails which keep it 

 company. The complement of eggs ranges from four to seven, and much variation exists in 

 the marking of the considerable series in my collection. Xo two of the seven nests are alike; 

 nor are the sets of eggs similar, although there is a geueral likeness running through the series. 

 The nests measure externally about 3:^ by 4 inches across by IJ to 2 inches deep, with the central 

 depression i to li inches deep, aud from 2 to 2i inches in diameter. The outer portion is usually 

 composed of bits of grass and moss, pretty compactly arranged, with the central cavitj- well lined 

 with some warm material, such as the hair of dogs and men, or Ptarmigan feathers, or a com- 

 bination of the three. One nest is built mainly of fine grass lined with a closely-felted layer ot 

 dogs' hair. The second nest has a thin layer of moss and grass followed by one of feathers, and 

 the six eggs it contains rest upon a layer of silky-brown club-mosses. The third is composed of 

 a felted layer of dogs' hair on the bottom, followed above by a thin layer of feathers; this is 

 succeeded by a still thinner layer of club-moss, aud the eggs rest upon a felted layer of dogs' hair. 

 The fourth nest is composed of a uniform loosely-joined structure of feathers and pieces of grass 

 all mingled into a heterogeneous mass. The ground color of the eggs varies from a pale-greenish 

 clay to a clayey white, over which extends a profuse confluent mottling, varying from slaty to red- 

 dish brown, which, in some cases, almost hides the ground color; in others the spots are large 

 and less numerous, and do not cover the shells so completely. The eggs of the same set usually 

 are of a similar shade and marking, and in but one set can the slightest traces of zigzag markings 

 be found about the larger ends. A series of thirty-two eggs ranges within the following limits: 

 Extreme length, .79; extreme breadth, .60; average length of entire series, .748; average breadth 

 of the entire series, .562; least length, .70; least breadth, .54. 



The following characteristics are taken from a series of twenty-six adult birds and eleven 

 young of the year, all obtained from the region about Saint Michaels : 



The sexes are very similar. In freshly-killed specimens the males are frequently brighter 

 colored than the females, but richly-plumaged females are much more brightly colored than the 

 duller males at the same season. 



Adult male and female in SiJrinff. — On the crown aud nape, extending down the sides of the 

 neck the color is clear ashy, becoming shaded more or less with brown in poor or worn plumage. 

 The back rich olive-green, especially upon the rump and upper tail-feathers, and extending to 

 just back of the ashy crown-patch. The intermediate region between the shoulders and on the 

 scapulars is shaded more or less strongly with brown, becoming ashy-brown or of a darker shade 

 than the crown in some specimens. The wings are brown. The tertiaries and coverts edged with 

 pale-yellowish white, the tips of the coverts forming two dull wing-bars. This light edging of 

 coverts varies in amount, and in worn specimens is sometimes nearly obliterated. The middle 

 tail-feathers are dark-brown, becoming nearly black in some specimens. Two outer tail-feathers 

 have their basal quarter brown, with a nan-owing band of the same exteiiding from the dark base 

 along the inner half of inner web, reaching nearly to the tip of feather. A narrow line of brown 

 close to the shaft on the outer web to the next to the outer feather. The remainder of these feathers 

 are white, including the entire tip of each and their shafts. The narrow white superciliary sti'ipe 

 usually commences at the nostril and reaches to the nape; but in some specimens it is obsolete in 

 front of the eye, and is frequently barely discernible. A dark-brownish ashy line includes the 

 lores, eye, aud ear-coverts. Chin white, shading into rich greenish-yellow, which occupies the 

 entire under parts, including the under tail coverts. The precise chain of the white area as well 

 as the intensity of the yellow varies greatly with individuals. The olive-green of back extends 

 on the sides of the neck and breast, forming a more or less obsolete and slightly clouded band 

 across the breast, the basal half of each feather being olive-green with a yellowish tip; some- 

 times the yellowish tip is obsolete, rendering the green more apparent. In some specimens sev- 



