Their eggs measure .79 of an inch in length and .59 in breadth. The ground-color is of a grayish-white so thickly flecked with fine ash-colored and black dots as to give the entire egg the effect of a uniform dark ashen hue. GENUS BUDYTES, CUVIER. _Budytes_, CUVIER, R. A. 1817. (Type, _Motacilla flava_, LINN.) [Line drawing: _Budytes flava._ 45912] The recent discovery of a species of yellow-bellied Wagtail in Norton Sound, by the naturalists of the Russian Telegraph Expedition, adds another member of an Old World family to the list of American birds. Much confusion exists as to the precise number of species in the genus, some grouping together as varieties what others consider as distinct species. There is an unusual degree of variation with age, sex, and season, and this, combined with strongly marked geographical peculiarities, renders the proper solution of the problem impossible to any but those having access to large series. Budytes flava, LINN. YELLOW WAGTAIL. _Motacilla flava_, LINN. Syst. Nat. I (1766), 33.—FINSCH & HARTLAUB, Vögel Ostafrikas, 268. _Budytes flava_, BON. (1838).—MIDDENDORFF, Sibirische Reise, II, ii (1852), 168.—DEGLAND & GERBE, Ornith. Europ. I (1867), 376.—BAIRD, Trans. Chicago Acad. Sci. I, ii, p. 312, pl. xxx, fig. 1; 1869.—DALL & BANNISTER, Tr. Ch. Ac. I, 1869, 127.—TRISTRAM, Ibis, 1871, 231.—FINSCH, 1872. SP. CHAR. Description of specimen No. 45,912, taken at St. Michael’s, Norton Sound, June 6, 1866, by H. M. Bannister. Above, including edges of upper tail-coverts, rich olive-green, the top and sides of the head and neck pure ash-gray; chin and well-marked stripe from nostrils over the eye to the nape, white; all under parts rich yellow, tinged with olive on the sides. Stripe from corner of mouth through the eye, and involving the ear-coverts, blackish-ash. Feathers of wings and tail dark brown; the coverts and secondaries edged with olive (showing the obscure light wing-bars), the longest of the latter edged externally with white; innermost quills edged externally with white. Outer three quills nearly equal and longest (the prolonged secondaries as long), the others graduating less. Outer tail-feathers and shaft white; the inner web edged externally with dusky, which, beginning at the base, runs out gradually to the edge, about half an inch from tip of feathers; second feather with rather less white, and with a narrow line of brown along the outer side of the shaft to within half an inch of the tip. Bill and legs blackish. [Illustration: _Budytes flava._] Dimensions (prepared specimen). Total length, 6.00; wing, 3.00; tail, 3.00; exposed portion of first primary, 2.30. Bill: length from forehead, 0.58; from nostril, 0.35; along gape, 0.57. Legs: tarsus, 0.91; middle toe and claw, 0.70; claw alone, 0.16; hind toe and claw, 0.65; claw alone, 0.36.