1900.] SHUFELDT—OSTEOLOGY OF THE STRIGES. Tale 
speaking above of the same condition as it occurs in Sfeotyfo. In 
Megascops the supraorbital processes are very nearly entirely aborted, 
and in young Burrowing Owls they are not very strongly pronounced. 
Both forms have symmetrical skulls, and in both the mandibles are 
almost entirely alike. 
With respect to the remainder of the skeleton, a Megascops has 
the four-notched sternum, in front of which the coracoidal grooves 
do not decussate, and the manubrium is small. The os furcula is a 
single U-arch and a weak one. At the distal end of the radius in 
the skeleton of the wing the os prominens is almost of rudimentary 
proportions. Finally, aside from specific variations in form, all 
the other components of the representatives of this genus agree with 
the bubonine type of structure. 
Already I have noted the fact above that Surzia u/ula approaches 
Speotyto closely in some of the characters of its skeleton. This is 
especially noticeable in the skull, where not only the general con- 
tour of that structure in the Hawk Owl strongly reminds one of the 
skull of Sfeotyto, but we find the resemblance to be real when 
we come to examine and compare some of the details. For in- 
stance, the external narial apertures are subcircular, or we might 
say broadly elliptical in Swvnza, just as they are in the Burrowing 
Owl; and, moreover, we find find the supraorbital processes to be 
of the same form in each. Swrnza further has the process on the 
upper side of the quadrato-jugal bar, although it is not as strongly- 
pronounced as it is in Sfeotyfo. Again, Surnia lacks a vomer, 
and the structures at the base of the cranium very closely resemble 
the corresponding ones in the Burrowing Owl. 
In the sqaumosal region, however, the foramen for the passage of 
the tendon of the temporal muscle does not form as it does in 
Speotyto, there being but a broad notch in the place of it. 
The mandibles are very much alike in the two birds; and the 
remainder of the skeleton in Suwrnza is fashioned upon the type in 
the bubonine Owls generally. 
Lastly, we must say a word about the skeleton in those dwarfs 
of the Strigine race, the Pygmy and Elf Owls. Personally, I 
have never examined the skeleton of a G/aucidium, but on the 
other hand I possess three skeletons of Mrcropallas whitneyt, a 
smaller Owl than any of the pygmies' (see Pl. XIV, Figs. 17 and 
18). 
1 T am indebted to Mr. Herbert Brown, of Tucson, Arizona, for this valuable 
