202 REPTILIAN ZONES 



or possibly also had strong streams developed in it by a 

 constant wind. 



The clay-pellet conglomerates in the Beaufort series 

 frequently contain rolled pieces of bone. Pebbles of 

 rock are very rare both in the conglomerates and the 

 other strata, and the few that have been found do not 

 reach a length of two inches. 



Coal has been found in thin layers in the Beaufort 

 beds (see p. 463). 



As this formation comprises a thickness of several 

 thousand feet of rock and covers a vast area, attempts 

 have been made to subdivide it into smaller groups on 

 either lithological or palseontological grounds. So far it 

 has been found possible, by means of the various rep- 

 tilian genera, to divide the formation into three groups, 1 

 each of which can be subdivided into zones: 



TT c , ( 6 Cynoqnathus beds 



Upper Beaufort { 



I > Procolophon ,, 



Middle Beaufort 4 Lystrosaurus ,, 



(3 Kistecephalus ,, 



2 Endothiodon ,, 



1 Pareiasaurus , , 



Since the reptilian remains are either scarce or absent 

 over wide areas it is obviously very difficult to determine 

 the limits of these zones in the field, and on the other 

 hand, owing to the small area yet mapped, it is not 

 quite known how far a lithological subdivision is possible 

 throughout the Colony, or whether such lithological 

 zones would, if traced out, coincide with those based on 

 the distribution of the fossils. 



1 K. Broom, papers read at the joint meeting of the B. and S. A. 

 A. A. S., 1905, vol. ii., p. 38 ; G. M., 1906, p. 29. 



