246 Mr. W. P. Pycraft on the 
border has not yet received the addition of the hemipterygoid 
which is made to it later. 
The pterygoid is rod-shaped and is continued forward along 
the whole length of the mesial rostral border of the palatine, 
terminating in a point (text-fig. 21). Thus at present there 
Text-fig. 21. 
Hemipterygoid region of the pterygoid of the same skull (text-fig. 18). 
pa.=palatine.  pt.=pterygoid. h.pt.=hemipterygoid. 
is no trace of the segmentation resulting in the formation of 
the temporary hemipterygoid, the ultimate fusion of which 
takes place with the palatine ; while this element and the 
pterygoid come to articulate by a joint (figs. 17, 18, 19). 
The Vertebral Column and Ribs. 
All the presynsacral vertebree are free and heteroccelous. 
The lower cervicals bear very small hypapophyses ; while 1—4 
of the dorsals are similarly protected, though these are rela- 
tively larger than in the cervicals. The last rib-bearing 
dorsal is included in the synsacrum, which is made up of 
12 vertebree. The dorsi-lateral processes of the sacrals are 
wanting. There are 7 free caudals, including the pygostyle, 
which is peculiar. Superiorly it is expanded to form a large 
pentagonal plate, which sends forward a long blunt spine, 
apparently representing an hypertrophied hypapophysis. 
There are 7 pairs of free ribs, of which all but the last two 
bear uncinate processes. Of these ribs, however, only four 
pairs articulate with the sternum, though the sternal segments 
of the last three pairs are of great length. 
The Sternum and Shoulder-girdle. 
The sternum of the Colies resembles that of the Capitonidee 
in that the posterior border of the sternal plate is deeply 
