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in mountain conditions; but before the end of the Carboniferous (Penn- 

 sylvanian?) these mountains were worn down to moderate relief, and 

 before the Cretaceous they were reduced to a peneplain. The earliest 

 peneplain represented in the region is, therefore, of pre-Cretaceous age. 



There is a lower peneplain, partially developed, probably of Tertiary 

 age, which cuts the Cretaceous as well as older rocks, and its surface is 

 ioo to 400 feet below that of the Cretaceous peneplain. A still later cycle 

 of erosion has been begun, and the valleys are now developing new plains 

 200 feet or so below the Tertiary peneplain. 



In the Wichita Mountains, there is nothing to indicate the date of the 

 deformation more closely than that it was somewhere between the Ordo- 

 vician and Permian; but, in view of the similarity of the structure and of 

 the stratigraphy in the two mountain systems, it is regarded as probable 

 that the deformation in the Wichita Mountains occurred at about the same 

 time as that of the Arbuckle Mountains. 



With reference to the reported ore deposits in the Wichita Mountains, 

 an elaborate series of tests of materials collected by Dr. Bain shows nothing 

 of economic importance. 



R. D. S. 



"On the Evolution of the Proboscidea, " Philosophical Transactions, 



London (B), Vol. CXCVI, pp. 99-118. 

 "The Barypoda, a New Order of Ungulate Mammals," Geological 



Magazine, October, 1904, p. 481. 



Of the numerous discoveries of Eocene vertebrates from Africa within 

 the past few years none are of more interest than certain forms referred to 

 the Proboscidea by Dr. Andrews, of the British Museum. He has shown 

 very clearly several of the early stages in the evolution of these animals from 

 small-skulled animals with an almost typical eutherian dentition, the first 

 premolar only being wanting, and the second incisor, the tusk of the ele- 

 phant only moderately developed and not at all porrected. Hitherto the 

 earliest of the Proboscidea known are from the lowest Miocene of France, 

 the order reaching America in the upper Miocene times. That Africa was 

 the original home of this order of ungulates now seems assured. 



Another paper of interest by the same author is that in which he defines 

 a new order of ungulates from the Eocene of Africa, which he has called 

 the Barypoda, a group somewhat intermediate between the Amblypoda 

 (Dinocerata) and the Proboscidea. 



s. w. w. 



