92 NORTH AMERICAN BIRDS. 



fifty specimens, including examples from all parts of its mnge. Upon a 

 close inspection of all the specimens in tliis extensive series, I was very 

 much surprised to find so little variation ; indeed, all the specimens are so 

 much alike that a detailed description of the colors of one would answer for 

 almost any individual. The siiade of color varies mainly according to the 

 age of the feathers, those newly acquired liaving a darkness of tint and a 

 softness of texture not seen in tliose more worn (as in midsummer dress), 

 which have a bleached or faded appearance. I fail entirely to detect the 

 different styles of plumage wliicli Mr. Cassin has described, and his diagnoses 

 of two supposed species will not at all hold good when applied to speci- 

 mens from eitlier of the two regions whicli they were considered to char- 

 acterize. 



Examining critically the large series at ray command, I find tliat the 

 jiriucipal discrepancy among individuals is the amount of featliering on the 

 tarsus ; tliis extending to the toes was svipposed to characterize the A. cuni- 

 cularia of North America the habitat of which was considered as restricted 

 in North America to the west of the Eocky Mountains (see Cassin, Birds of 

 North America, as cited above) ; the nearly naked tarsus was believed to be 

 characteristic of the A. Injpugcca, as restricted, and the habitat assigned to 

 this was "from the ^Mississippi River to the Ilocky Mountains." Now, 

 dividing the series under examination into two sets, according to this fea- 

 ture, we have, first, nmuvluria iVom the following localities : from tlie Ilio 

 Grande, all specimens but one ; Tongue liiver, ilontana ; and Petaluma, 

 Santa Clara, and San Francisco, California. Next, hyporjtcu represents the 

 following localities, besides places within the range ascribed to it : Utah ; 

 Lower California, including Cape St. Lucas, all specimens ; San Diego, Cali- 

 fornia, several specimens ; Santa Barbara, San Francisco, Sacramento, and 

 Fort Tejon, California ; and Tamaulipas, Mexico. 



Tliough we have but one species or form in North America, the South 

 American bird is different : this is the true cunicularia of Jlolina, and 

 though not specifically distinct from our bird, is nevertheless an easily 

 recognized geograpliical race. It is larger, the wing measuring from 7.U0 to 

 7.50, instead of 6.40 to 7.00 ; the l)rown of tlie plumage is appreciably darker 

 than that of most specimens of lujpoycca, but less extended ; on the outer 

 web of the primaries tlie white spots are larger, — sometimes confluent along 

 the edge, — and on tlieir inner webs tlie wliite largely jm'vails, the dusky 

 bars appearing only towards the ends; the outer tail-feather is almost 

 wholly ^vliite, instead of having brown bars, broader than the white ones. 

 Of the var. cunimdaria there are eight specimens in the collection (chiefly 

 from Paraguay, Buenos Ayres, and Chile), while numerous others, in various 

 collections, have been examined besides. All the American forms of this 

 subgenus seem clearly referrible to one species, as being at the most but 

 geographical races. 



Habits. Tlie Burrowing Owl of North America inhabits the country 



