ORDER ANOMODONTIA. IO57 



lary series. The nostrils are large and lateral ; and at the junction 

 of one of the bones of the palate with the maxilla, the tooth-bearing 

 surface is wide, and supports four parallel rows of small obtuse teeth. 

 In Pantylus, which was originally described as a Labyrinthodont, 

 the teeth are more equal in size. 



Suborder 2. Theriodontia. — This suborder, which is taken 

 (after Dr Baur) to include the Pelycosauria of Professor Cope, is 

 characterised by the absence of a bony roof over the quadratic 

 region of the skull, and the presence of only a single wide temporal 

 arch (fig. 979), apparently consisting of a conjoint squamoso- 

 maxillary and quadrato-maxillary arcade. The mandible has no 

 lateral vacuity. 



In some cases, as in the American forms, the vertebras are still 

 notochordal ; intercentra may be developed, to which the capitular 

 heads of the ribs are articulated, and there are not more than 

 two or three sacral vertebras. The dentition is fully developed. In 

 the palate of the African forms at least the maxillae develop palatal 

 plates to floor the nasal passage, and thus produce tall and nearly 

 vertical posterior nares, strikingly like those of Mammals. The 

 premaxillae remain separate. 



In those of the typical African forms in which the pelvis is 

 known, the ilium is somewhat intermediate between that of the 

 Pariasauria and Dicynodontia, having a distinct but small obturator 

 foramen. The humerus is usually more or less of a Dicynodont 

 type, having expanded extremities, and the entepicondylar foramen 

 with its lower aperture opening on the palmar aspect of the bone 

 (fig. 982); there is generally a marked thin flange on the postaxial 

 border opposite this foramen which does not occur in the Dicy- 

 nodonts. 



Although evidently nearly related to the Pariasauria the present 

 group departs farther from the Labyrinthodont type, as is shown by 

 the loss of the roofing bones in the quadratic region, as well as of 

 the superior temporal arcade, and by the absence of sculpture or 

 mucous canals on the skull. This advance is also indicated by the 

 development of secondary posterior nares, by the fuller attachment 

 of the ilia to the sacrum, and the relatively larger centra of the 

 vertebrae of the higher types ; as well as by the development of the 

 obturator foramen in the pelvis. 



Family Tapinocephalid^e. — This family may be taken to in- 

 clude two gigantic Anomodonts from the Karoo system of the Cape, 

 described under the names of Tapi?iocephalus and Titanosuchus. 

 The former is known typically by the extremity of the cranium ; the 

 vertebrae probably belonging to it having short and notochordal 

 centra. A pelvis, found in association with some limb bones, has 

 been described under the name of Phocosanrus, but there is no 



