632 



NORTH AMERICAN BIRDS. 



served as the basis of all the descriptions of the species which is justly 

 considered one of tlie rarest in the North American fauna. 



Habits. In regard to the habits, distribution, or general history of this 

 very rare species, but little is known, only one specimen having been met 

 with. This was procured by j\Ir. Audubon's party to the Yellowstone Eiver, 

 in Dakota, on the last day of July, 1843. That it is a resident M'here ob- 

 tained, certainly during the breeding-season, is a natural inference from the 

 circumstances of its capture. That it may be a common bird in certain 

 other portions of the region, immediately north of Dakota, is quite probable. 

 Its close habits, as described by Mr. Audubon, favor its escaping notice wher- 

 ever it may exist. 



The specimen was met with in a wet place, overgrown closely by a kind 

 of slender rush-like grass, from the midst of which the notes of these birds 

 were heard, and at first mistaken for those of the Marsh Wren. A search 

 was immediately instituted for the singers, whicli Mr. Bell soon ascertained 

 could not be the Wren in question, the notes being much softer and more 

 prolonged. Much difficulty was encountered in the endeavor to raise them 

 from the long close grass to which they closely confined themselves, and 

 they were several times nearly trodden on before they would take wing, 

 almost instantaneously realighting within a few steps, and running like mice 

 through the grass. After a while two were shot while on the wing, and 

 proved to be adult male and female. The party found this species quite 

 abundant in all such situations, and there seems to have been no doubt that 

 it was breedino-. 



Genus PASSERCULUS, Bonap. 



Passerculus, Boxap. Comp. List Birds, 1838. (Type, Fringilla savanna.) 



Gen. Cir.\R. Bill moderately conical : the lower mandible smaller ; both outlines nearly 



straight. Tarsus about equal to the middle 

 toe. Lateral toes about equal, their claws 

 ialling far short of the middle one. Hind 

 toe much longer than the lateral ones, reach- 

 ing as far as the middle of the middle claw ; 

 its claws moderately curved. Wings unusu- 

 ally long, reaching to the middle of the tail, 

 and almost to the end of the upper coverts. 

 The tertials nearly or quite as long as the 

 primaries; the first primary longest. The 

 tail is quite short, considerably shorter than 

 the wings; as long as from the carpal joint 

 to the end of the secondaries. It is emar- 

 ginate, and slightly rounded ; the feathers pointed and narrow. 



The essential characters of this well-marked genus lie in the elongated 

 wings, longer than the tail, the tertiaries equal to the primaries, the first 



710J> 



Passerculus savanna. 



