I 



RAPT ORES. 103 



On careful and minute examination of several specimens from Cali- 

 fornia and Oregon, in the collection of the Expedition and others, we 

 find them to be strictly identical with the common bird of the States 

 on the Atlantic. This species has, therefore, a very extensive range of 

 locality, embracing nearly the whole of North America. Numerous 

 specimens from a variety of localities west of the Mississippi River, 

 collected by the parties that survej^ed routes for a railroad to the 

 Pacific Ocean, are now also in tlie National Museum. 



Though considered by ornithologists generally as identical with the 

 European Circus cyaneus, this bird is really very different, and, of course, 

 fully entitled to a specific designation. In fact, no person accustomed 

 to making investigations in Zoology, would, for a moment, suspect the 

 identity of these two species, with facilities before him for comparing 

 them, 



3. Family STRIGIDiE.— The Owls. 

 1. Genus STRIX, Lhm. Syst. Nat. I, p. 131 (1766). 



1. Strix perlata, Licldenstein. 

 Sfrix perlata, LiCHT. Verz. p. 59 (1823). 



This is one of several species of owls, which bear more or less inti- 

 mate resemblance to the common barn owls of Europe and North 

 America, Strix flammea and i)ratincola, and appears, in fact, to re- 

 present the group now regarded as forming the typical genus Strix, in 

 South America. The species of this eminently natural group are for 

 the greater part only to be distinguished by rather minute and fre- 

 quently apparently unimportant characters, which are, however, found 

 to be constant and characteristic. To these characters, different natu- 

 ralists ascribe very different degrees of value. 



Of this South American species, which we regard as distinct from 

 any other, notwithstanding the opinions of nearly all the late autho- 

 rities, several specimens are in the collection of the Expedition. It 

 is smaller than its near relative of North America, Strix lyratincola, 

 Bonaparte, and is more nearly the size Strix flammea, Linn., of the 

 old world, which otherwise also it much resembles. From the latter, 



