Maryland Geological Survey 55 



Upper Devonian of Maryland, one in the upper part of the Portage and 

 the other about 600 feet above the base of the Chemung. 



In 1911 Dr. E. M. Kindle's paper on " The southerly extension of the 

 Onondaga Sea in the Allegheny region" appeared. It contains a brief 

 statement of the paleontologic and stratigraphic data which the author 

 considers as showing the continuation of the Onondaga fauna from the 

 Delaware Eiver southwesterly to Tennessee. 



Kindle's detailed paper, of which the above was in the nature of an 

 abstract, appeared in 1912 as Bulletin 508 of the U. S. Geological Survey 

 under the title The Onondaga Fauna of the Allegheny Eegion. 



The Pawpaw-Hancock Polio of the U. S. Geological Survey was pub- 

 lished in 1912 in which the Lower Devonian was discussed by G. W. Stose 

 and E. 0. Ulrich, and the Middle and Upper Devonian by C. K. Swartz. 



The limits and correlation of the various divisions of the Devonian were 

 substantially the same as those recognized in the present volume. 



BIBLIOGRAPHIV 



ScHOPF, Johann David. Beytrage zur mineralogischen Kenntniss 

 des ostlichen Theils von ISTordamerika und seiner Gebiirge. Erlangen, 

 1787, 194 pp. 



1809 



Maclure, William. Observations on the geology of the United States, 

 explanatory of a geological map. 



Trans. Amer. Philos. Soc, o. s., vol. vi, 1809, pp. 411-428. 



1817 

 Maclure, Wm. Observations on the geology of the United States of 

 America; with some remarks on the effect produced on the nature and 

 fertility of soils, by the decomposition of the different classes of rocks. 

 12mo, 130 pp., 2 plates. Pluladelphia, 1817. 



' This bibliography does not include general works but is limited to works 

 discussing the Maryland area and adjoining areas in Pennsylvania and West 

 Virginia. Publications in which Maryland materials are discussed are also 

 cited. 



