468 MARIUS R. CAMPBELL 



the base of the series, except in reverse order as shown in Fig. i. 

 If the writer has observed correctly (and the facts seem to be 

 bevond question), it is possible for Dr. White to trace sandstone 

 in outcrop from the well-known Mahoning of Pennsylvania to 

 the Charleston of the Kanawha valley, but that does not neces- 

 sarily mean that they are of the same age. Dr. White contends 

 that he has traced the coals in a similar manner, but from the 

 great difficulty in tracing coal beds and in identifying their out- 

 crops from- place to place, the writer declines to' accept this sort 

 of evidence when in conflict with that afforded by the sandstone 

 beds and the fossil plants which accompany them. 



Marius R. Campbell. 



