456 LAMELLIROSTRAL SWIMMERS — ANSERES. 



8. Leucopareia. THE WHITE-CHEEKED GOOSE. 



Anser canadensis, Pall. Zoog. K.-A. II. 1826, 230 (nee Linn.). 



A^iscr hucoparcius, Brandt, Bull. Se. Ac. St. Petersb. I. 1836, 37. 



Bernicla leucopareia, Cass. Illustr. B. Cal. Tex. etc. 1853, 272, pi. 45. — Bairu, B. N. Am. 1858, 



xlix. 765 ; Cat. N. Am. B. 1859, no. 568. 

 Branta canadensis, var. leucopareia, CouES, Key, 1872, 284 ; Check List, 1873, no. 485 a. 

 Branta canadensis, b. leucopareia, CouES, B. N. W. 1874, 554. 

 Bernicla canadensis leucoparia, Ridgw. Pr. U.S. Nat. Mus. Vol. 3, 1880, 203 ; Nom. N. Am. B. 1882, 



no. 594 6. — CouES, Check List. 2d ed. 1882, no. 703 (part). 



Hab. Of canadensis proper, temperate North America in general, breeding in the United 

 States and British Provinces ; casual in Europe ; occidentalis, the northwest coast (California to 

 Sitka) ; Hukhinsi, breeding in the Arctic districts, migrating south, chiefly through the Missis- 

 sippi Valley and westward ; leucopareia, Pacific coast chiefly, breeding along the coast of Alaska, 

 but frequently straying inland during migrations. 



Sp. Char. Adult : Head and neck deep black, the former with a white patch covering the 

 throat and extending up over the cheeks to behind the eyes, growing gradually narrower above, 

 the upper outline usually more or less truncated, this white patch, however, sometimes interrupted 

 on the throat by a narrow black stripe or isthmus. Very rarely, a broad white band, more or less 

 distinctly indicated, crosses the forehead between the eyes. Black of neck fre([uently bordered 

 below by a white collar, more or less distinct. Upper surface grayish brown, varying from almost 

 cinereous to umber, each feather bordered terminally by a paler shade ; lower parts with the ex- 

 posed surface of about the same shade as the tips of the feathers of the upper parts, the concealed 

 portion of the feathers of the shade of the prevailing color above — this much exposed along the 

 sides and on the flanks. Primaries and their coverts plain dusky, the former growing nearly black 

 terminally. Anal region, crissum, and lower tail-coverts immaculate pure white. Tail plain deep 

 black ; rump plain blackish slate. Bill and feet deep black. Young : Similar to the adult, but 

 the colors duller, the markings less sharply defined ; black of the neck passing gradually below 

 into the grajnsh of the jugulura ; white cheek patches usually finely speckled with dusky ; light- 

 colored tips to the contour-feathers broader. Dovmij young : Above, including an occipital patch, 

 golden olive-green ; beneath, pale-greenish ochre, the head rather deeper. 



Total length, about 20 to upwards of 40 inches ; wing, 13.60-21.00 ; culmen, .95-2.70 ; depth 

 of maxilla at base, .60-1.20; width, .52-1.20; tarsus, 2.10-3.70; middle toe, 1.80-3.40. Tail- 

 feathers, 13 to 20. 



If, as seems to be the case, all tlie North American Wild Geese similar to Bernicla canadensis in 

 color are of one species, there is proliably no feral bird and few domesticated kinds, which vary to 

 such great extremes of size. A series of upwards of fifty specimens, carefully measured at the same 

 time, gives the above results, the variation amounting to the following percentums of the maxi- 

 mum measurements, only adult l:)irds being measured : Wing, 35.24 per cent ; culmen, 64.81 per 

 cent ; tarsus, 43.25 per cent ; middle toe, 47.06 per cent. 



The only character which seems to approach constancy is the number of tail-feathers, tlie smaller 

 specimens usually possessing 13 or 14 to 16, and the larger 18 to 20 ; but the number varies with 

 the individual, some examples, referable to Hutchinsi on account of size, possessing 18 or more, 

 and vice versa. After a very careful consideration of all the facts involved, we feel constrained to 

 look upon all the North American Wild Geese resembling B. canadensis in coloration as of one spe- 

 cies, no matter what their size may be, it being scarcely possible to define the line between even 

 geographical races. The following, however, is an attempt at a subdivision of the species such as 

 seems warranted by the material in hand ; but it may be premised that examples not infrequently 

 occur which are as properly referable to one as to the other : — 



A. Tail-feathors usually 18 to 20 ; size usually large. 



1. Canadensis. Lower parts nnich puk-r than the upper, the light brownish gray some- 

 times fading gradually into the white of the anal region ; white cheek-patches usually 

 confluent on the throat, and white collar round lower neck in the winter plumage very 

 indistinct or obsolete on account of the light color of the jugulimi. Wing, 15.60-21.00 



