a4 MR. W. P. PYCRAFT ON THE MORPHOLOGY 
In Podargus humeralis the pterygo-palatine articulation is so 
oblique, that at first the pterygoid appears to be an unsegmented 
bone as in the Paleognathe. 
The peculiar form of the pterygoid in Podargus at first much 
disconcerted me, seeming, as it did, to show that the unseg- 
mented, pointed, pterygoid was not alone peculiar to the Palszo- 
gnathe. A more careful study, however, has placed its real 
nature beyond all possibility of doubt—it has modified a cup- 
shaped articular surface into an elongated facet. The palatines 
in Podargus, as in Steatornis, are peculiar in that they send 
inwards a ventral keel to meet in the middle line, thus forming a 
tubular passage. In Steatornis the floor of this tube lies further 
forward than its roof, underlying the vommer. In Podargus the 
floor of the tube lies directly under its roof. 
Summary. 
Briefly, the result of this paper has been to show that the 
differences between the Palewo- and Neognathine palate are those 
of degree and not of kind. 
The Paleognathine is undoubtedly the older form. In it 
the vomer and pterygoid are uninterruptedly connected, one 
with another, throughout life; whilst the palatines remain per- 
manently separated one from another caudad, and are connected 
only with the maxillo-palatine processes distad. 
In the Neognathz the vomero-pterygoid relations are inter- 
rupted by the segmentation of the pterygoid distally ; whilst the 
palatines, caudad, have moved inwards to meet in the mid- 
ventral line beneath the distal ends of the pterygoids, with which 
they eventually fuse, and, distad, have lost their primitive con- 
nection with the maxillo-palatine processes, and have established 
a new connection with the palatine processes of the premaxilla. 
The fusion of the distal ends of the pterygoid with the under- 
lying palatine is accompanied by segmentation of the former 
and the formation of a pterygo-palatine joint. 
In my recent memoir on the Paleognathe I inadvertently 
described the inward movement of the palatines as having 
resulted in “thrusting the vomer forwards” (p. 206). This is 
inexplicable, since it is obvious, from the very next sentence, that 
T had not lost sight of the fact that this bone still retains its 
primitive connection with the pterygoid. That both pterygoid 
