TITLES AND ABSTRACTS OF PAPERS 153 



feet above the old Pittsford black shale horizons. Casts of salt hopper crystals 

 occur in the same slab, with nearly perfect exuvia, under which nestle dozens 

 of Leperditise. The individuals are distributed profusely through a layer of 

 dark gray shales twenty inches thick, inclosing a calcareous seam with Em- 

 melezoe decora. Ceratiocaris salina also appears, but the chief zone of this 

 is next beneath. 



The indications are not favorable to a fresh-water habitat for this mero- 

 stome. 



In the absence of the author, the Secretary then presented the follow- 

 ing paper, which on account of lack of time had to be given in abstract : 



ECONOMIC VALUE OF PALEONTOLOGY 

 BY RALPH ARNOLD 



PRESENTATION OF PAPERS ON STRATIGRAPHY 



The reading of stratigraphic papers transferred to the Society's pro- 

 gram from that of the Geological Society of America was then com- 

 menced. The first paper was presented by the author and was illustrated 

 with charts. 



AGE OF CERTAIN PLANT-BEARING BEDS AND ASSOCIATED MARINE 

 FORMATIONS IN SOUTH AMERICA 



BY EDWARD W, BERRY 



(Al)stract) 



A discussion of the scattered occurrences of fossil plants in Colombia, Ecua- 

 dor, Peru, and at various localities in Chile, together with the associated ma- 

 rine faunas. A correlation of these is made with the geological formations of 

 the Panama Canal Zone and Graham Land. The results show a remarkably 

 uniform sequence in the successive movements of the strand-line and a paral- 

 lelism in the Mesozoic and Cenozoic history of the Pacific Coast region from 

 the Isthmus of Panama southward to Antarctica. 



The next two papers were presented by the senior author in each case 

 and illustrated with numerous diagrams and sections. On account of 

 the shortness of time still available, these two papers were combined. 

 They were discussed by Messrs. David White and I. C. White. 



TYPICAL SECTION OF THE ALLEGHENY FORMATION 

 BY CHARLES K. SWARTZ AND HARVEY BASSLER 



{Abstract) 



The importance of a clear understanding of typical sections of geological 

 formations is fully recognized. The published descriptions of the typical sec- 



