The Peneplain. — Tarr. 351 
THE PENEPLAIN. 
By R. S. Tare, Ithaca, N. Y. 
Contents. 
Page 
Reasons for the paper :i.51 
Definition of a peneplaiti 352 
General acceptance of the peneplain 353 
Improbability of the peneplain explanation 353 
Lack of eviilence of ancient peneplains 356 
Evidence against the peneplain theory 361 
Alternate hypotheses 364 
Conclusion 369 
Reasons for the Paper: — Five years ago doubts concern- 
ing the value of the evidence of peneplains, which had pre- 
viously come to my mind, were distinctly strengthened as the 
result of study in the highlands of New Jersey. I was, there- 
fore, led to call in question the explanation which even then 
was being quite generally accepted. So widespread was the 
adoption of the idea that I hesitated to publish these doubts 
and decided to give the matter more thought. After two or 
three years a paper was- prepared stating my objections, and 
sent to Prof. W. 3*1. Davis for his consideration. It did not 
convince him, nor did his comments upon the paper convince 
me that the objections were unsound. 
Nevertheless, the failure to convince Prof. Davis induced 
me to give the question still more study, with the result that 
the longer I have thought upon the matter, and the more ex- 
tended my field observations have become, the stronger grows 
the conviction that the peneplain explanation is in error. 
Therefore, notwithstanding the fact that nearly all AmericaJi 
geologists have adopted the peneplain explanation, and that 
no one has publicly questioned it, I have decided at last to 
state my objections in print.* 
I have been led to this decision in the belief that it shouUl 
be done. Every month, and sometimes oftener, one finds a 
statement concerning a newly discovered peneplain. Thev 
arc being found nearly everywhere. Indeed they arc an- 
nounced upon the most meagre evidence, and oftentimes with 
no statement of evidence whatever. Frequently a new pene- 
plain is mentioned as one might state the discovery of a delta 
*I am indebted to Prof. J. C. Branner, Prof. I. C. Russell. Prof. 
A. C. Gill and Mr. J. B. Woodworth for kindly reading- and com- 
menting upon this paper. 
