790 



SYSTEMATIC SYNOPSIS. — PYGOPOBES. 



841. 



front and sides of the head. A patch of sharp white streaks on the throat, and another largei 

 triangular patch of the same on each side of the neck lower down, the two last nearly or quite 

 meeting behind, separate in front. Sides of breast striped with black and white. Entire upper 

 parts, wing-coverts, inner secondaries, and sides under the wings, glossy black ; aU except tie 

 sides thickly marked with white spots; those of the scapulars, tertials, and middle back, large, 

 square, and regular; those of other parts smaller, oval, smallest on rump, most numerous on 

 wing-coverts. Upper tail-coverts greenish-black, immaculate. Wing-quiUs brownish-black, 

 lighter on inner webs. Under surface of wings, axUlars, and under parts generally from the 

 neck, pure white ; the lower beUy with a dusky band. The white throat-patch consists usually 



_ of five or six streaks; in 



this, as in the lateral 

 neck-stripes, the individ- 

 ual feathers are broadly 

 black, with sharp wliite 

 fedges toward their ends. 

 The. texture of these 

 feathers is peculiar, — the 

 outer surface is hollowed, 

 with raised edges of spe- 

 cially firm, smooth, pol- 

 ished character, so that 

 these patches may be felt 

 as well as seen. The 

 Fig. 530. -Common Loon. (After Wilson.) white spots On the back 



occur in a pair on each feather near its end, their aggregation in any region being therefore 

 determined by the size of the feathers themselves. Young : Bill smaller than in the adult, 

 bluish- white, with dusky ridge: Iris brown. C.rown and hind neck dull brownish-black ; 

 other upper parts similar, but the feathers, especially of the fore back, with light gray edgings. 

 Primaries black, with brown inner webs. Tail-feathers with gray tips. Traces of lighter and 

 darker liueation on sides of breast. Sides of head mottled with ashy and whitish; chin, throat, 

 neck in front, and whole under parts, white. Dimensions : length 31 to 36 inches; extent 

 about 53.00; wing 12.50 to 14.25; bill 2.75 to 3.00 along culmen; gape 4.00 to 4.25; height 

 at nostrils, about 0.80; width there about 0.40; tarsus 3.00 to 3.50; middle toe and claw 

 4.25 to 5.00. Inhabits the Northern Hemisphere. In winter, generally dispersed in the U. S. ; 

 breeds in portions of the U. S. and thence northward. Eggs 2, 3.50 X 2.25, elongate and 

 pointed, dull greenish-drab, with dark brown spots. Young covered with stifBsh black down. 

 C. t. a/clamsi. (To Dr. C. B. Adams.) YELLOVf -BILLED Loon. Larger than C. torguatus, 

 with the bill rather larger and somewhat differently shaped and colored. BUI about equalling 

 head, longer than tarsus, much compressed, tip very acute, not at all decurved, the culmen 

 being almost perfectly straight, as the commissure also is. Gonys straight or nearly so to the 

 angle, which is very prominent. (Pig. 530 shows the shape of the biU better than it does that 

 of No. 840, for which it is intended.) Frontal antiae reaching beyond middle of nostrils. BQl 

 light yellowish horn-color, only dusky at base. Head and neck deep steel-blue, with purplish 

 and violet reflections, glossed only on the cervix with green. Throat-patch of white streaks 

 smaller than in torquatus, but the individual streaks larger, as are those of the neck-patches. 

 White spots of upper parts larger than in torquatus, longer than broad instead of square on the 

 scapulars and tertials. Bill along culmen 3.50 to 3.75; along gape 5.00 to 5.25; height at 

 nostrils 0.95 to 1.10 ; width 0.40 to 0.50 ; tarsus 3.50 ; outer toe 4.65 to 5.10. General dimen- 

 sions somewhat exceeding those of torquatus. Arctic America, common; perhaps specifically 

 distinct from the last. 



