562 PROCEEDINGS OF THE PHILADELPHIA MEETING 



Following the reading of the memoirs, the Secretary made announce- 

 ments concerning matters of business and the program, and Mr N. H. 

 Darton, Committee on Photographs, announced that the collection of 

 photographs was displayed in an adjoining room. 



The President declared the scientific program in order. The first paper 

 presented was the following : 



DEVELOPMENT AND MORPHOLOGY OF FENESTELLA 

 BY EDGAR R. CUMINGS 



[Abstract"} 



Thin sections and serial sections of exceptionally well preserved bases of Fenestella 

 (semicoscinium of authors) from the Hamilton of Thedford, Ontario, show the exact 

 size and shape of the primary zocecium (Protcecium) and the morphology and 

 orientation of the primary buds. The protcecium consists of an elongate tubular 

 zocecium with a large basal disk. It is without hemisepta. Morphologically, it is 

 strictly comparable to the protcecium of Cyclostomata (of Tubulipora, Lichenopora,, 

 etcetera). The two primary buds arise from the dorsal face of the protcecium, 

 usually just above the basal disk, and are very symmetrically orientated with ref- 

 erence to the dorso-ventral plane. They are of about the same shape as the pro- 

 tcecium and somewhat smaller. Each of these buds produces a single bud in the 

 first tier, and an additional bud arising from one of the latter completes the first 

 tier of buds — six zocecia, including the protcecium. Zocecia of the shape charac- 

 teristic of the adult Fenestella colony do not appear till the colony begins to branch. 

 Hemisepta have not been seen in any of the earlier zocecia. These studies seem 

 to definitely relate Fenestella genetically to the Cyclostomata. The Cyclostomata are 

 therefore the ancestors of the Cryptostomata and through them of the Chilostomata. 



Remarks on the paper were made by H. M. Ami. It is printed in full 

 in the American Journal of Science, volume xx, pages 169-177. 



The second paper was 



BEARING OF SOME NEW PALEONTOLOGIC FACTS ON NOMENCLATURE AND 

 CLASSIFICATION OF SEDIMENTARY FORMATIONS 



BY HENRY SHALER WILLIAMS 



The paper was discussed by the President, H. M. Ami, I. C. White, 

 N. H. Darton, A. C. Lane, D. W. Langton, W. B. Clark, A. W. Grabau, 

 W. N. Rice, and the author. It is printed as pages 137-150 of this 

 volume. 



The last paper of the morning session was the following : 



GEOLOGICAL BOOKKEEPING 

 BY JAMES F. KEMP 



The subject was discussed by H. S. Williams, A. P. Coleman, and the 

 author. The paper is published as pages 411-418 of this volume. 



