pat R. Owen on the Solitaire. 91 
There is, as is well-known, no “ maxillo-palatine or pre- 
vomerine bone” in the bird’s skull distinct from the proper 
maxillary or proper palatine. The latter bone (ib. ib. 20) 
speedily coalesces with the premaxillary (22) in front, and 
the maxillary (21!) above, as does this with the premaxil- 
lary in front and with the malar bone behind. ‘Their respec- 
tive limits are definable by their unconfluent condition in the 
immature bird. 
In Pezophaps the persistent linear suture between the pala- 
tal part of the maxillary and the palatine commences 1 inch 
10 lines from the tip of the beak ; it defines a linear tract of 
the maxillary of 1 inch 3 lines extent. External to this 
suture is the palatine tract, coalesced with the maxillary, in 
breadth 2 lines, in length 10 lines; when the palatine be- 
comes free, it is twisted on itself, forms a vertical plate of 3 to 
4 lines depth, and sends off from the median side, of a hinder 
extent of 7 lines, the horizontal plate, which bends mesiad. 
Between these right and left median plates of the palatines is 
an interval of 24 lines. The interpalatine vacuity in advance 
of the horizontal plates is 43 lines across. The upper parts of 
the hinder five lines of the palatines are applied to the convex 
sides of the presphenoids. The pterygoids (21) abut against 
the basisphenoid immediately behind the palatines, each 
pterygoid diverging and expanding to abut against the tym- 
panic. ‘The maxillo-palatal cleft is long and of moderate and 
uniform width ; the interpalatal cleft is wider until the inner 
plates are developed. 
The beak of the bird serves as both hand and mouth; the 
apex of the wedge, in these functions, is driven against re- 
sisting bodies sometimes of considerable hardness. In all 
birds the opening and closing of the bill are acts of prehen- 
sion. In many birds these latter movements are not limited 
to the lower jaw, but a mechanism exists for raising the upper 
jaw as well. ‘The joint between the base of the bill and the 
cranium is made flexible by diverse modifications. The tym- 
panic is fashioned in relation therewith. It is connected by 
two beams or columns of bone on each side of the skull with 
the fore part of the upper jaw. The outer beam, commencing 
forward at the side of the maxillary, is continued by the malo- 
squamosal style to the outer side of the transversely expanded 
lower part of the tympanic. The inner beam, commencing 
by the palatal process of the premaxillary, is continued back- 
ward by the palatine and pterygoid bones to the inner side of 
the lower end of the tympanic. Any swinging to and fro of 
this bone upon its single or double upper ball-and-socket joint 
is transferred to the “core”’ by the four beams converging 
