224 



PROP. H, G. SEELEY ON THE 



[Mar. 21, 



wliere the foramen is distinct, ovate, and larger (on the left side 

 of the head), and is between the malar, postorbital, squamosal, 

 and quadrate. It is a linear gap in the bones in one specimen. . 

 It is much smaller than the vacuity in the side of the skull in 

 Palceohatteria. The extension of the foramen downward to the 

 quadrate bone involves no substantial difference from the British 

 Museum specimen R. 1999, so that the name Procolophon Icdiceps 

 may be used for that specimen, in preference to P. triyoniceps 

 used in Phil. Trans. 1889, pi. 9. 



The Teeth. — Usually the mandible is in close contact with the 

 skull, so that the teeth are not seen, except on their external or 

 internal aspects. The incisors are rather longer and stouter in 

 aspect than the maxillary or molar teeth. They are conical, bixt 

 flattened on the inner surface, which carries a few vertical ridges. 

 I have failed to obtain evidence of implantation in sockets by 

 making a vertical section. 



Text-fiij. 33. 



Palate of FrocoJophon cuneieeps, showing the molar teeth ; from Donnybrook. 



A specimen in the British Museum, B. 794, was developed in 

 fruitless search for the occiput, biit now shows with exceptional 

 clearness the structure of the quadrate I'egion and the palate (text- 

 fig. 33). The pterygoids and vomera are shown bearing teeth, the 

 palatine bones, palatine plates of the maxillary bones, and the 

 maxillary are seen on the palate. The most interesting feature 

 of the dentition is the crowns of the maxillary teeth, which un- 

 expectedly have a transverse molar form, as in the lizard Tejus. 

 They are six in number on each side, wide transversely, with distinct 

 inner and outer cusps, and with the inner and outer triturating 

 suifaces separated by interspaces which appear to have received 



