OF THE PALATE OF THE NEOGNATH A. 353 
The peculiarly modified distal extremity of the free pterygoid 
the adult skull and the connection of this extremity with the 
fused hemipterygoid and palatine are features of great interest. 
The resultant oblique joint appears to be one which allows of 
but little motion. A comparison of the figures will make the 
peculiarities of this palate easier to understand. 
Jt has been suggested (p. 348) that the dorsal keel of the 
pterygoid in the Lari might have some significance. We would 
remark here that it is possibly by the segmentation of a strongly 
keeled pterygoid that the large plate-like hemipterygoid of such 
forms as Megalema, for instance, ay have been derived. Later 
on in development the keel of the shaft of the pterygoid may 
have been lost. 
Before closing this paper, I would draw attention to the modi- 
fications of the pterygoid in certain of the Caprimulgi. 
Steatornis affords a most perfect illustration of the segmenta- 
tion of the pterygoid. In a nestling in the Museum Collection, 
this bone (PI. 32. fig. 5) is continued forward as an unbroken and 
completely ossified rod to terminate in a sharp point above a ves- 
tigial vomer. The palatines have met together mesially beneath 
these pointed pterygoid extremities, which as yet remain one with 
the main shaft. In the adult (fig. 5 a) segmentation has taken 
place, not immediately behind, but some distance distad of, the 
extreme posterior ends of the palatines. The hemipterygoid 
fusing with the palatine, an oblique palato-pterygoid joint is 
formed (cf. fig. 5 6). 
The other Caprimulgine forms to which allusion has been made 
are mentioned here, not on account of the hemipterygoid, about 
which I can at present say nothing, but because of the peculiar 
modification which the palato-pterygoid articulation undergoes. 
In Caprimulgus europeus the pterygo-palatine articulation is a 
perfectly normal (Neognathine) one; the pterygoid shaft articu- 
lating by a joint with the extremity of the palatine. In 
Eurostopus nigripennis the pterygoid articulation is as in Capri- 
mulgus, but the palatines send backwards on to the pterygoids 
two minute processes, one on either side. In Nyctibius this 
backward extension of the palatines has encroached still further 
upon the pterygoids so as to underfloor these for a considerable 
extent, thus entirely masking the nature of the pterygo-palatine 
articulation from the ventral aspect of the palate. 
