492 SHUFELDT. [Vol. XVII. 



Owing to the considerable size of the gaping aural entrances, 

 the basitemporal region is much contracted, but the basitem- 

 poral bone itself is more ample, as we find that in the embryos 

 it extends out laterally to assist in forming the antero-inferior 

 parietes of the tympanic walls upon either side. 



The auditory cavities and the ossified stapes, as well as the 

 cranial cavity proper, all present their usual ornithic characters, 

 departing in no very marked manner from ordinary birds. All 

 these cranial structures just named remind us more or less 

 of the corresponding ones in the skull of the fowl. 



K pterygoid is a short, thickish bone, somewhat twisted upon 

 itself, and presents upon its midshaft (opposite the corre- 

 sponding basipterygoid process) an inconspicuous, low and 

 rounded eminence. In other species the summit of this is 

 faceted, ^^xo. palatines do not appear to articulate with each 

 other in the middle line, but are accurately moulded upon the 

 side of the rounded rostrum, upon which they glide in life, — 

 the mesial lamina being extended forwards as a pointed process, 

 also in the closest contact with the rostrum. This is the spine 

 that has been by others erroneously termed the vomer among 

 the Pici. 



The postero-external angles of the palatines are very much 

 rounded off, and upon the whole these bones are but feebly 

 developed. Anteriorly, the prepalatine portion of either one 

 is carried forwards as an exceedingly slender rod, widely 

 separated from the fellow of the opposite side. 



This very narrow prepalatine part fuses anteriorly with the 

 nether surface of the lengthy maxillo-palatine of the same side, 

 and fails to reach the premaxillary. All pigeons, so far as I 

 am at present aware, are typically schizognathous birds, and the 

 nasals are extremely peculiar bones. For, in addition to being 

 acutely forked, the premaxillary process is markedly long and 

 slender, running almost to the apex of the beak, closely moulded 

 upon the underside of the coossified, slender nasal processes 

 of the premaxillary. The delicate "external process" of a 

 nasal is also rather long, and fuses with the upper edge of the 

 maxillary process of the premaxillary of the same side. On 

 top of the skull, in the middle line, the nasals unite with each 



