1900. ] SHUFELDT—OSTEOLOGY OF TH STRIGES. (Val 
FIG. 11. The ventral aspect of the sixth to the twelfth cervical vertebrae of an adult 
specimen of the Snowy Owl (Nyctea nyctea). Natural size and from the same 
specimen which furnished the skull shown in Fig. 8. (Coll. U.S. Nat. Mus., 
No. 18458.) 
PLATE XIII. 
FIG. 12. Basal aspect of the skull of an adult specimen of the Screech Owl 
.(Megascops asio), Natural size, mandible removed, but with the circlets of 
sclerotals of the eyes left zz stw in the orbits. When photographed the skull 
was slightly rotated to the left. (Spec. No. 18987 of the Coll. U. S. Nat. Mus.) 
FIG. 13. Superior aspect of the skull of an adult specimen of Pulsatrix tor- 
guato from Nicaragua. Natural size and mandible removed, which latter is 
shown in Fig. 15. (Coll. U.S. Nat. Mus., No. 18350.) 
FIG. 14. Superior aspect of the skull of an adult specimen of the American Hawk 
Owl (Surnia ulula caparoch). Natural size and mandible removed (in author’s 
private collection). 
FIG. 15. Superior aspect of the lower mandible of an adult specimen of Pzlsatrix 
torguata. Natural size and from the same specimen which furnished the skull 
shown in Fig. 13. 
Fic. 16. Left lateral view of the trunk skeleton, shoulder-girdle and the femora of 
‘a specimen of the Screech Owl (adult), MZ asio. Natural size, and belonged to 
the same specimen which furnished the skull shown in Fig. 12. The os fur- 
cula is broken near its lower part. 
BVATE XV 
Fic. 17. Left lateral view of the entire skeleton of an adult specimen of the Elf Owl 
(Micropallas whitneyi). (Ligamentous preparation.) Very slightly reduced from a 
specimen in the author's collection, and presented to him by Mr. Herbert Brown, 
of Tucson, Arizona (May, 1890). The windpipe is broken and protrudes in front 
of the cervical vertebrze. The circlet of sclerotal plates are in the left orbit. This 
. is the skeleton of one of the smallest of the existing species of Owls in the world. 
Fic. 18. Superior aspect of the skull of an adult specimen of the Elf Owl ( Micro- 
pallas whitneyi). Very slightly reduced and mandible not removed. Another 
specimen other than the one shown in Fig. 17, but with the same history. 
FIG. 19. Left lateral aspect of the skull and mandible of an adult specimen of the 
Screech Owl (Megascofs asio). Very slightly reduced and with the sclerotal 
plates of the left eye zz sztu. Same skull as shown in Piate XIII, Fig. 12. 
Fic. 20. Anterior aspect of the sclerotal plates of the right eye of an adult speci- 
men of the Great Horned Owl (Budo virginianus). Very slightly reduced, and 
from the same skeleton to which the skull belonged shown in Plate XII, Fig. ro. 
Fic. 21. Superior aspect of the skulf of an adult specimen of the American Barn 
Owl (Strix pratincola). Very slightly reduced. Hyoid arches wired to the 
skull 27 s¢¢#, and this is seen through the left orbit. (Spec. No. 18196 of the Coll. 
U. S. Nat. Museum, and the same specimen as shown in Plate XV, Fig. 24. 
Mounted in the cases of the Osteological Department, and kindly loaned by Mr, 
F. A. Lucas.) 
PLATE XV. 
FIG. 22. Palmar aspect of the right humerus of an adult specimen of the American 
Long-eared Owl (Asio wilsonianus). Author's collection, and taken by him 
