1400. ] SHUFELDT—OSTEOLOGY OF THE STRIGES. 687 
the thorax. These terminate in pointed extremities and articulate 
with the vertebra by both capitula and tubercula, the former on 
elliptical facets, placed vertically on either side of the centrum at 
the anterior margin of the neural canal, and the latter on rounded 
facets beneath the transverse processes. The tubercle on one of 
these ribs is nearly as long as the neck; at the junction on the pos- 
terior side is found a pneumatic foramen of considerable size. 
These ribs are more or less flattened above from before backward, 
being convex anteriorly, concave posteriorly, becoming rounded 
below. From third to ninth vertebra, inclusive, appear beneath 
the vertical canal anteriorly well-developed styliform parapophysial 
processes, directed backward and downward. They are _ best 
marked on the segments on the middle of the neck. There is no 
instance in this bird of these processes being produced so far back- 
ward as to touch the next vertebra below; their tips, as a rule, 
about overhanging the middle of the centrum of the vertebra to 
which they belong. We have found in specimens of Budo virgint- 
anus the parapophyses of the fourth vertebra overlapping and touch- 
ing the fifth for a millimetre or more. The third and fourth cervi- 
cals have, beneath in the median line posteriorly, strongly devel- 
oped hypapophyses, quadrate in form, a process that exhibits itself 
anteriorly on the fifth vertebra merely as a small tubercle. On the 
sixth this tubercle has disappeared, and has been supplanted by two 
others that are now found just within the periphery of the anterior 
facet of the centrum beneath, and on the parapophysis of each side, 
they being inclined toward each other. ‘These processes, now a 
‘double hypapophyses developed from the parapophyses, continue to 
increase in size and inclination toward each other on the next three 
vertebra, so that on the ninth, where they last appear, they nearly 
form a closed canal. The passage between them is intended for 
the carotids, to which they afford protection. ‘The hypapophysis of 
the tenth, eleventh and twelfth vertebrz is single, large, quadrate 
and directed forward and downward. ‘There are three on each of 
the last two vertebree, each having an independent root, the two 
lateral ones directed downward, forward and outward, with charac- 
teristics similar to the one in the median line. Several pneu- 
matic and nutrient foramina perforate each cervical vertebra at 
various points, except in the axis and atlas, where, after diligent 
search, aided by the lens, we have signally failed to discover them. 
Dorsal Vertebre; Vertebral and Sternal Ribs ; Sternum.—The 
