718 SHUFELDT—OSfTEOLOGY OF THE STRIGES. [Dee. 7, 
These diminutive birds, so far as we can judge from Afcropallas, 
possess a skeleton that has in it many characters that remind us of 
the skeleton in Sfeotyto. The general form of the skull is much 
the same, although it will be seen that in JA@icropadllas the fronto- 
supraorbital processes are almost entirely aborted. Both species 
apparently lack a vomer, while, too, both have the peculiar expan- 
sion on the upper side of the quadrato-jugal bone. This is very 
conspicuous in AZcropal/as, and appears to have something to do 
with making a more complete bony periphery for the orbit. The 
sclerotal platesof the eyeball rest against it below. Superiorly, 
round behind and at the sides, AZ/crvopallas has an unusually ro- 
tund cranium, and shows in the squamosal region a notch for the 
transmission of the tendon of the temporal muscle. No asym-, 
metry is noticeable in the skull, and the arrangement of the bones 
of the roof of the mouth are very mucl) as we found them in the 
Burrowing Owls. A good-sized ramal vacuity exists in either ramus 
of the mandible and the hyodean apparatus essentially agrees with 
Speotyto. Other points worthy of notice in the skeleton of AZicro- 
pallas are: it has in the arm a pneumatic humerus, and a very 
small os prominens at the distal end of radius over the wrist. Its 
os furcula is feeble, but thoroughly united below; the manubrium 
of the sternum is well pronounced, and the sternum itself four- 
notched. When 2” sctu the coracoids are well apart at their sternal 
extremities, and the shafts of those bones are each pierced by a fora- 
men, ina manner similar to what we find inso many Hawks and Owls. 
Its vertebre and ribs, between skull and pelvis, agree with the bubo- 
nine type of Owls generally, but it seems to possess a fewer number of 
caudal vertebrae, never as many as eight free ones, as we find in other 
representatives of this group of birds. Another structure we must 
observe is its pelvis ; this differs considerably in pattern from what 
we see as a rule in most other Owls, for in some respects it reminds 
me not a little of the pelvis as I have found it in certain Passerine 
types. In it the pelvic basin is not noticeably contracted nor deep ; 
and what is still more striking, there is no inclination for the post- 
pubic bones to curve toward each other posteriorly. They project 
material, and at the time I received it there was not a skeleton of a MZtcro- 
pallas in any of the collections of the larger institutions of the United States nor 
in Europe. Moreover, I understand, the bird, through the persistent destruction 
of collectors, stands much in danger of becoming extinct. 
lst tai ee ne eee ae 
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