92 NORTH AMEIMCAN' JSIUDS. 



fifty specimens, including cxanijilos iroiii all jiarts of its I'anuo. V\)im a 

 close inspection of all tlio sj)ociniens in tliis extensive series, I was very 

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

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

 almost any individual. The shade of color varies niaiidy according to the 

 age of the feathers, those newly acijuired liaviug a darkness of tint and a 

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

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

 different styles of idumage wliicli Mr. Ca.ssin has described, and his diagnoses 

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

 mens from either of the two regions which they were considered to char- 

 acterize. 



Examining critically the large series at my command, I llnd that the 

 principal disoreiiancy among individuals is the amount of feathering on the 

 tarsus ; tliis extending to the toes was supposed to characterize the A. cnni- 

 cidaria of North America the habitat of which was consid(ued as restricted 

 in Xorth America to the west of the Itocky ^Mountains (see (,'assin, Birds of 

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

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

 this was "from the Missi.ssippi IJiver to the I'ocky Mountains." Now, 

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

 ture, we have, first, ninicuhiriu from the followiiig localities : from the Ilio 

 Grande, all .specimens but one; Tongue Ifiver, Montana; and IVtaluma, 

 Santa Clara, ami San Francisco, California. Next, /(//^w/rtTt represents the 

 following localities, besides places within the range ascril)ed to it : Utah ; 

 Lower Cidifornia, including Cape St. Lucas, all ,s])ecimens ; San Diego, Cali- 

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

 Fort Tejon, California ; and Tamaidipas, Mexico. 



Though we have but one S])ecies or form in Xorth America, the South 

 American bird is different: this is the true vuaieuldria of Molina, and 

 though not specifically distinct I'rom our liird, is nevertheless an easily 

 recognized geographical race. It is larger, tlie wing measui'ing from 7.00 to 

 7.50, instead of 0.40 to 7.00; the brown of the plumage is apjjreciably darker 

 than that of most specimens of Jii/poi/cca, but less extended ; on the outer 

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

 the edge, — and on their inner webs the wliite largely ])r('vails, tlie du.sky 

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

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

 Of the var. cunictdarw there are eight specimens in the collection (chietly 

 I'rom Paraguay, Buenos Ayres, and Chile), while numerous others, in various 

 collections, have been examined besides. All the American i'orms of this 

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

 geogra])hical races. 



Habits. The Burrowing Owl of North America inhabits the country 



