VERTEBRATE PALAEONTOLOGY IN 1913 649 



first of these (pp. 509-16) are discussed the structure and 

 affinities of Bolosaurus, a genus originally described by Prof. 

 Cope on the evidence of a skull from the Lower Permian of 

 Texas, who regarded it as representing a distinct family of the 

 Cotylosauria, more or less nearly related to the Diadectidce. In 

 the light of new material and fresh investigations, Dr. Broom 

 is of opinion "that the Bolosanridce represent a primitive group 

 of theromorphs near to the common ancestors of the pely- 

 cosaurs, varanosaurids, and dromasaurians. Even without 

 knowing anything of the Bolosauridce, we know that these 

 three groups had a common post-cotylosaurian ancestor, and 

 while the bolosaurids are too specialised to have been ancestral, 

 they are probably members of the suborder that included the 



Fig. 6.— Skull of Pantylus cordahts, to show the closed temporal region of 



the Cotylosauria. 



(From Bull. Amer. Mns. Nat. Hist. It has not been considered necessary to give the 

 names of the constituent bones indicated by letters.) 



common ancestor. If we place the Bolosauridce in this central 

 position we get a satisfactory explanation of its seeming varied 

 affinities." It is added that a suggested affinity between Bolo- 

 sciurus and the European Permian genus P alceohatteria has 

 been rendered the more probable by the discovery of sclerotic 

 plates in the orbits of the former, which have long been known 

 in those of the latter. 



In the second article {pp. cit. pp. 527-32) the author considers 

 the cotylosaurian genus Pantylus, likewise described by Cope 

 on the evidence of remains from the Permian of Texas. Dr. 

 Broom's paper is of too technical a nature to be referred to 

 in any more than an incidental manner. At present the genus 

 is known only by the skull (fig. 6) ; but even from this evidence 



