386 PROCEEDINGS OP THE ACADEMY OF 



Description. [No. 19,686, adult male, Fort Simpson, 30 Apr. I860.] The 

 bill is small, short, stout, thick at the base, regularly conical, somewhat com- 

 pressed, but not so much so as in A. Unarms, dusky throughout, except the 

 cutting edges. The tip of the upper mandible slightly overhangs that of the 

 lower. The culmen, gonys, and commissure from the angle are all about 

 straight. The nasal plumuli are exceedingly full, dense and heavy, reaching 

 about half way to the top of the bill. They are very much heavier than in 

 Unarms, and though absolutely shorter than in that species, they are compara- 

 tively as long, owing to the smaller size of the bill. The front is dusky like 

 the lores, and more broadly so than Unarms, but the feathers are tipped with 

 whitish, which gives the forehead a hoary appearance. There is an appreci- 

 able light superciliary streak, more distinct than in Unarms. The lores, and a 

 gular spot are dusky. The crown is deep crimson, exactly as in Unarms. The 

 general color of the upper part is that of Unarms ; but the dusky streaks are 

 smaller, more numerous and indistinct, especially on the anterior portions of 

 the back ; the yellowish is much lighter than in Unarms, approaching to white. 

 Towards the rump the yellowish tint disappears before the streaks do, leaving 

 a space streaked with dusky and pure white. The rump is pure white, imma- 

 culate, with a delicate light rosy tinge. The upper tail coverts have slightly 

 dusky centres. The wings and tail are much as in Unarms. The primaries 

 are very narrowly edged and tipped with white, the edging becoming quite 

 broad on the inner secondaries. The median and greater coverts are narrowly 

 edged, and broadly tipped with white, forming two transverse bars. The 

 second primary is longest ; the first and third equal and scarcely shorter ; the 

 fourth a little less, the fifth very much shorter. The under parts are white 

 the throat, breast and belly with a light tinge of rosy, many shades lighter 

 than in specimens of Unarms of the same age and season. The sides are 

 streaked with dusky ; but the streaks are very sparse, and illy-defined, much 

 more so than in Unarms. The under tail-coverts are almost immaculate. The 

 feet are brownish black, as are also the claws ; the feet are much smaller, and 

 weaker than in Unarms, the difference being especially noticeable in the length 

 of the toes. The middle toe without the claw is shorter than that of linariut, 

 by about the length of the last joint of the latter species. 



Variations by age, sex, c. As is usual throughout this genus, evidences of 

 immaturity are to be found in the faintness, or entire absence of the rosy tint 

 of the breast and rump, these parts being lightly streaked with dusky ; in the 

 restriction of the crimson of the crown to a frontal patch, and in a general 

 light yellowish or buffy suffusion about the head and fore-breast. The suffu- 

 sion, however, does not appear to be as deep as that of liiiarms, and some other 

 species. The females are hardly distinguishable from the young males ; but 

 the crimson of the crown has usually an orange reflection, and the breast and 

 rump are more thickly streaked. The size appears rather less. 



Accidental Variations. The variations to which this species is subject, other 

 than those of sex and age, are very great, much more so than exist in any 

 other species of the genus. The dimensions of the whole bird ; the size, shape 

 and color of the bill; the color and number of the streaks above and on the 

 sides ; the extent and purity of the white of the rump, &c, are all liable to 

 great variations. Indeed, almost the only character that is perfectly constant 

 lies in the feet, in their absolute size, and the relative length of the tarsus and 

 toes. With this variation, however, the specimens all have a general resem- 

 blance to each other, which, together with the character of the feet, render it 

 easy to distinguish them from any other species of the genus. The precise 

 combination of characters varies with almost every specimen ; and there are. 

 moreover, intermediates to be found between all extremes ; entirely removing 

 the doubt which might otherwise arise, as to whether there were not two or 

 more species combined in the series of specimens. 



In an extensive series, comprising thirty-seven specimens, I have found the 



[Nov. 



