326 ON THE CLASSIFICATION OP BIRDS. 
shall, nevertheless, enumerate such of the subordinate 
forms as appear either to lead to, or represent, the other 
genera. AVe make it the primary distinction of the 
birds of this group, that two out of the three primary 
characters, viz. the facial disk, the operculum, and the 
great development of the ear, should be found in all; 
hence we include in it the common long and short-eared 
owls of Britain, as aberrant forms or subgenera, repre- 
senting the rasorial or crested type of the genus. The 
crest, or egrets, of these two birds, indeed, would place 
them in an arbitrary system with the genuine horned 
owls ; but as there must be a passage from one to the 
other, we consider that the two birds in question con- 
stitute that passage : they retain the first and strongest 
character of their own genus, yet they are furnished 
with egrets, in order that they may connect the oper- 
culated with the horned division. Leaving this, we 
have a third type in the Strix Tengmatmi of the 
Northern Zoology, to which, in all probability, we 
should refer tile various small species of Europe (still 
but imperfectly known under the common name of 
.S', passerina), together with those of temperate Ame- 
rica. These latter owls are known by their small 
size ; short feet, thickly covered with feathers to the 
root of the claws ; and by the operculum being long and 
narrow, the conch forming almost a semicircle.* * This, 
lor reasons which will appear hereafter, is doubtless the 
tenuirostral division of the present genus, and it forms 
our subgenus Scotophilus, Hitherto we have had owls 
only with short, and almost even, tails ; but in the 
gigantic Strio? cineriaf the tail is long, cuneated, and 
the feathers pointed : the facial disk, as in all the pre- 
to examine the ears of preserved specimens of the foreign species in mu. 
seums; and, even when they are in skins, what with the carelessness of 
the original preserver, and the shrinking of the neighbouring parts, the 
investigation will always be imperfect, and sometimes faulty. 
* Such is the description of ,S'. Tengmatmi by Ur. Richardson in Northern 
Zoology, vol. ii., which we subsequently verified ; and yet we find this very 
bird arranged by Cuvier in the same genus with tlle great snowy owl, which 
has hardly any disk, no operculum, and a very small conch ! 
t Northern Zoology, ii. pi. dl. 
