154 PROCEEDINGS OF THE PALEONTOLOGIOAL SOCIETY 



SUMMARY OF THE RESULTS OF INVESTIGATIONS OF THE FLORIDIAN AND 

 BAHAMAN SHOAL-WATER CORALS 



BY T. WAYLAND VAUGHAN 



(Abstract) 



The author will briefly summarize the results of eight seasons of field and 

 laboratory work on the Floridian and Bahaman shoal-water corals. The dif- 

 ferent factors influencing their life will be considered, namely, relations to 

 currents and waves, character of bottom, temperature, light, salinity, atmos- 

 pheric exposure, and depth of water. Experiments on the reactions of corals 

 to nutrient and non-nutrient particles and the food of corals will be described, 

 and the results of experiments to ascertain the duration of the free-swimming 

 larval stages and the growth rate of corals will be given. The bearing of the 

 investigations on geologic interpretation will be indicated. 



Following this paper was a strati graphic one, illustrated with lantern 

 slides and charts. 



CORRELATION OF THE UPPER CRETACEOUS DEPOSITS OF THE ATLANTIC 

 AND GULF COASTAL PLAIN 



BY L. W. STEPHENSON 



(Abstract) 



The Upper Cretaceous sediments of the Atlantic and Culf Coastal riain are 

 chiefly medium to fine-grained clays, sands, chalks, and marls ranging in 

 origin from those laid down on low coastal plains, in estuaries, or in very 

 shallow seas to those formed in waters for the most part less than 50 fathoms 

 deep, though perhaps in part in waters exceeding 100 fathoms deep. 



The formations into which these sediments may be grouped are related to 

 each other not as the leaves of a book, a succession of regular layers of uni- 

 form thickness, but, viewed in a section parallel to the strike, they appear as 

 a series of intertonguing lenses, great and small] the age relations of which 

 can be determined only on the basis of paleontologic criteria. 



In our present state of progress the fossils most usable in determining the 

 age relations of the marine sediments are tbe representatives of the genus 

 Exogyra, which were adapted for life in all but the very shallowest of the 

 Upper Cretaceous marginal seas and which underwent evolutionary changes 

 with sufficient rapidity to form faunal zones traceable through contempora- 

 neous formations, whether they be chalks, sands, clays, or marls. 



At 5.30 the Society adjourned until the following day. 



At 8 o'clock the memhers attended the address of Professor Coleman, 

 retiring President of the Geological Society of America, in the general 

 assembly hall of the Medical School, and at 9.15 they participated in 

 the smoker to the several societies, given by the Geological Society of 

 Washington, at the Cosmos Club. Following the smoker a number of 



