96 BULLETIN UNITED STATES GEOLOGICAL SUKVEY. IVolV. 



Anser ccerulescens, (L.) Yiem.— Blue Goose. 



Sexes are alike in color. 



With the size and exactly the form of the next species, hut the plumage ashy, varied 

 with dark brown ; the head, upper neck, tail-coverts, and most of the under parts 

 white ; the wing-coverts silvery ash. 



It is a singular fact that I have never observed this Goose during the 

 spring migrations when the preceding one is so abundant, and with 

 which it first makes its appearance here in the fall and is afterwards con- 

 stantly found mixed with the flocks of that Goose, and associating vnth 

 it on terms of such familiarity as to suggest to me the query whether 

 there may not be a doubt as to its distinctness from a hyperboreiis, and 

 whether it may not in reality be the young of that Goose, or a semi- 

 melanotic condition thereof. I have seen flocks of a liyperhoreus cov- 

 ering acres of ground, with here and there a Blue Goose scattered appar- 

 ently indiscriminately through th^ flock. I have also seen them asso- 

 ciated on the wing. The case of this Goose and that of the Black-bellied 

 Plover constitute the only exceptions falling under my notice of a mi- 

 gratory bird appearing in the fall that does not pass this region during 

 the spring migrations. This Goose departs with the preceding about the 

 end of October. 



Branta canadensis, (L.) GcQxy.— Canada Goose; Common Wild Goose. 



Sexes are alike in color. 



Tail normally 18-feathered. Grayish-brown, below paler or whitish-gray, bleaching 

 on the under tail-coverts, all the feathers with lighter edges ; head and neck black, 

 with a broad white patch on the throat mounting each side of the head; tail black, 

 with white upper coverts ; bill and feet black. About 36 inches lono- ; mn"- 18-^0 • 

 tail 6-L-7i ; bill l|-2. '' ~ ' 



Passes this region from the 1st to the 30th of Aprfl in large numbers j 

 it loiters but a few days at this season (a very few may breed near the 

 head of the Coteau). Eeturns about the 15th of September, after which 

 date it is very abundant until its final departure for the season, usually 

 about October 31. 



Anas boschas, lAmi.— Mallard. 



Sexes are not alike in color. 



This Duck and the seven next described are known as the ''Eiver Ducks," and are 

 distinguished from the " Sea Ducks" by having the hind toe simple. 



$ with the head and upper neclc glossy green, succeeded by a white ring; breast 

 purplish-chestnut; tail-feathers mostly Avhitish ; greater wing-coverts tipped with 

 black and white, the middle quills with a violet marking, black-bordered; bill green- 

 ish-yellow ; feet orange-red. 9 with the wing as in the $ ; head, neck, and under 

 parts pale ochrey, speckled and streaked with dusky. Leng-th about 24- wins 

 10-12. ■ o ; 8 



This Duck appears to enter this region about April 10, and remains 

 until October 30 ; breeds sparingly in the sloughs ; at first, the MaUard 

 is not near as abundant as some of the other Ducks are, but as faU 

 approaches it becomes very common. 



