VERTEBRATES FROM PERMIAN OF TEXAS 399 



there is no triangular area, and the posterior foramen opens on 

 the summit of a ridge directly posterior to the elevated edge of 

 the cotylus. Fig. 4 shows the scapula of the right side of 

 Embolophorus dolloviafius, with the almost perfect clavicle in its 

 normal position. 



At this point may be noted a peculiar relation which exists 

 between the scapulae of the American and the African reptiles. 

 In Clepsydropsidae there is no trace of the attachment of the 

 clavicle to the scapulae, except in the problematical facet figured 

 bv Cope as possibly forming an articulation for the clavicle. In 

 the Dicynodonts and the Theriodonts there is a distinct process 

 on the scapulae for the clavicle, and this exists even in Pareiasaii- 

 rus where the epiclavicle is still present. In Cy?iognathus this 

 process has developed into a strong scapular spine which occu- 

 pies the upper edge of the scapula nearly in the same position as 

 is the scapular spine of the Monotremes. 



Zatrachys crucifer. sp. no v. 



A single neural spine, No. 171 of the Chicago collection, 

 indicates a new form which I have referred to a new species of 

 the genus Zatrachys Cope. As shown in Fig. 5, the spine has a 

 cruciform shape with a sharp upper portion and short lateral pro- 

 cesses. The posterior zygapophyses are preserved and are 

 relatively small. The upper faces of the lateral processes and 

 the apex of the spine are pitted by a deeply marked rugosity so 

 that the whole upper surface of the spine is excavated by deep 

 pits of a size and depth seen before only in the larger amphib- 

 ians, Eryops, and Cricotus. The lower surfaces of the later pro- 

 cesses and the sides of the base of the spine are smooth. The 

 anterior and posterior edges of the apex are free from the deep 

 pits and are marked by a narrow space of striations showing that 

 the spine was overlapped by the edges of some other element ; 

 it is evident from the shape of the spine that this could not have 

 been the edges of the adjacent spine, but must have been an 

 extra element intercalated between the spines, probably one of 

 the dermal ossifications such as occur along the spine of Pareia- 

 saurus. The nearest approach to this condition is found in the 



