72 Albany Mti.seum Reconh. 



broad as the interorl)ital region. The jtarietal i-egion ina^y be 

 divided into three parts separatetl by two longitudinal i-idges — a 

 median part formed by the parietals and jireparietal, and pierced 

 by a large parietal foi'am.en, and two hireial portions formed by 

 the postorbitals ("postfrontals"). The occiput slopes forwards. 

 The stjuamosals are large bones, very similar to those in Oudeno- 

 doH. The maxillaries resemble considerably the maxillaries in 

 Oudenodon, but have a series of teeth in the posterior part. In 

 the type specimen the maxillary teeth are not shown, but in a 

 specimen of the same genus in the South African Museum the 

 maxillary teeth are well shown. The lower jaw is very much 

 broader and flatter than in any other Anomodont with which I 

 am acquainted. In each dentary is a sei'ies of teeth, tliere being 

 apparently five mature teeth with evidences of succeeding teeth 

 on the inner sides of some of them. In structure the,y agree 

 closely with the teeth of Pristerodoii 7nackai/i — the front being 

 smooth and the posterior edge forming a series of den.ticulations. 

 The molar teeth agree so closely with those of Pristerodon, that it 

 might readily be thought that the present species is a species of 

 Pristerodon. The type of Pristerodon described by Huxley is in 

 a very imperfect condition, and if only the tj-pe were known, I 

 should have referred the Pearston specimen to Pristerodon. In 

 the South African Museum there is a more perfect specimen of 

 Pristerodon collected many years ago by Mr. Mackay at East 

 London, and apparently from the same locality as the type. In 

 the Capetown specimen there is a well-developed canine which at 

 once distinguishes Pristerodon from the form under consideration. 

 In the London specimen, Dr. Smith Woodward informs me that 

 he is unable to find any trace of a canine ; but as the anterior i)arr 

 of the skull is very badly preserved in the type specimen, it is 

 possible that the canine is lost. On the present evidence I think 

 it better to conclude that I'risferodon had a well-developed canine, 

 and that the Pearston specimen represents an allied genus in 

 which the canine is wanting. 



Among the Anomodonts we have quite a number of pairs of 

 genera, tusked and tuskless, and it is just possible as has been 

 suggested that the tusked are the males and the tuskless the 

 females. Thus we have Dici/nodon and Oudenodon, Cri/pto- 

 cynodon and Esoterodon, Pristerodon and Opisthoctenodon^ and 

 some specimens of Cistecephalus with tusks and others apparentlj- 

 without. A very strong argument against this view is foimd in 

 the fact that Lystrosaurus is always tusked. Though dozens of 



