52 Introduction 



map showing the areal distribution of the ditferent formations and soils, 

 while the legend gives the thickness and a very- condensed description of 

 the geology and soils. Schuchert in 1903 published a paper " On the 

 Lower Devonic and Ontario formations of Maryland " in which the de- 

 posits of the Cumberland Ba^in are quite fully described. Under the 

 Devonian the Coeymans, Xew Scotland, and Becraft limestones of the 

 Helderberg and the Orislvany formation are discussed in considerable 

 detail and paleontologic evidence given for their correlation. It contains 

 a complete composite section from the Juniata formation to the base of 

 the Marcellus shale, in which the thickness and description of zones, 

 locality of sections and correlation with New York formations are given. 



In 1903 H. S. Williams' bulletin on The Correlation of Geological 

 Faunas appeared. This contained a brief discussion of the Komney forma- 

 tion of western Maryland. Professor Williams found all of the dominant 

 species of the Tropidoleptus carinatus fauna in the list of Komney species 

 furnished him by the MTiter and concluded that " This is sufficient to es- 

 tablish the extension of the Tropidoleptus fauna, in its integrity, as far 

 south in the Appalachian trough as Maryland.'' 



In 1904 the writer published an article entitled the " Description and 

 Correlation of the Komney fonnation of Maryland " which gave a con- 

 densed description of the formation together with some account of the 

 evidence favoring the correlation of the lower member with the Marcellus 

 shale and the upper with the Hamilton beds of New York. The European 

 equivalents and the general distribution was also discussed. 



In 1906 Dr. E. M. Kindle published a paper on the Faunas of the 

 Devonian section near Altoona, Pa., a locality about 65 miles northeast of 

 Cumberland. This paper recognizes the Oriskany, Marcellus, Hamilton, 

 Nunda (Portage), and Chemung faunas near Altoona and therefore is 

 important in corroborating the correlation of the Maryland Devonian 

 formations with those of New York. 



The Physical Features of Maryland, by Professors Clark and Mathews, 

 published in 1906, contains an accurate condensed account of the Devonian 

 period. The Lower Devonian is divided into the Helderberg formation, 

 composed of the Coeymans, New Scotland, and Becraft members, and the 



