TITLES AND ABSTKACTS OF PAPERS 205 



PRESIDENTIAL ADDRESS 



At 2.30 p. m. the Society convened to hear the address of the retiring 

 President on the subject, 



THE PALEONTOLOGY OF ARRESTED EVOLUTION 

 BY DR. KUDOLF RUEDEMANN 



Following Doctor Euedemann's address the presentation of papers on 

 General and Invertebrate Paleontology was resumed. The first paper 

 was a report of progress and was illustrated by lantern slides. Discussed 

 by Charles Schuchert. 



PRESENT STATUS OF AREAL MAPPING IN THE COASTAL PLAIN AND OF THE 

 PALEONTOLOGIC INVESTIGATIONS IN THE COASTAL PLAIN, PANAMA, AND 

 THE WINDWARD ISLANDS 



BY T. WAYLAND VAUGHAN 



(AJ)stract) 



This paper presented in outline the purpose and plan of the studies in areal 

 geology and paleontology in the Coastal Plain of the Atlantic and Gulf States, 

 in the Canal Zone, and in the West Indies. The present status of the investi- 

 gations was indicated by maps and tables, which were shown on the screen. 



An interesting and ingenious interpretation of the stratigraphic rela- 

 tions of certain graptolite shales and continental deposits of Great Britain 

 ^^'as given by Doctor O'Connell, who presented the following paper, illus- 

 trated by charts. Discussed by Messrs. Puedemann, Grabau, Twenhofel, 

 Schuchert, and Bassler. 



WERE THE GRAPTOLITE-BEARING SHALES, AS A RULE, DEEP OR SHALLOW 



WATER DEPOSITS? 



BY AMAUEUS W. GRABAU AND MARJORIE O'CONNELL 



{AT)stract) 



By most authors graptolite shales have been considered as deep water 

 deposits. This interpretation is questioned on the following grounds: (1) An 

 examination of the most important graptolite-bearing formations of Europe 

 and of North America shows a vast preponderance of clastic material of very 

 shallow water, if not of actually continental origin, the graptolite-bearing beds 

 being very thin intercalations in each series. Often evidence of shallow water 

 conditions is shown in the beds themselves. (2) The great scarcity of normal 

 marine organisms and their very frequent absence in the beds between the 

 graptolite layers negatives the marine origin of these sediments. (3) The im- 

 probability of graptolite remains sinking to the floor of the relatively deep 

 ocean, especially where strong surface currents transport them, seems generally 



