RECORDS OF MEETINGS 355 



17). There is very great difference in extent of igneous effect in ttie differ- 

 ent fundamental formations. I judge that there is a strongly 

 selective influence exerted by the formations themselves. 

 General: 



18). As a result, all of the formations are complex in composition — iu 

 part priuiur\-. in jiart metamorphic. in part introduced, and 



19). All of the formations are also complex in structure — in part of pri- 

 mary sedimentary control, in part induced by metamorphism (re- 

 crystallization), in part of primary igneous habit, in part a pri- 

 mary structure emphasized by its control over igneous injection, 

 and in part purely secondary dynamic modification. 



The Section then adjourned. 



A. B. Pacini, 



Secretary. 



SECTION OF BIOLOGY 



9 February, 1914 



Section met at 8 :15 p. m.. Professor Eaymond C. Osbuxn presiding. 

 The minutes of the last meeting of the Section were read and approved. 

 The following programme was then offered : 



W. D. Matthew, Some Eemarkable Extinct Animals of 



South America. 

 Hobert Cushman Murphy, Habits, Anatomy and Eelationships of 



the Sea Elephant (Mirounga leonina). 



Summary of Papers 



Dr. Matthew: The American Mviseuni collections of extmct South 

 American mammals includes a series of eight mounted skeletons repre- 

 senting the Edentates, hoofed animals and Carnivores that flourished 

 during the PampEPan and Santa Cruzian epochs. The chief characteris- 

 tics of these animals were outlined. 



Mr. Murphy had studied the Sea Elephants at South Georgia, a small 

 island in the Antarctic Ocean, where he had secured a series of specimens 

 of them and of other animals for the American Museum of Natural His- 

 tory and for the Brooklyn Institute of Arts and Sciences. He exhibited 

 a remarkable series of photographs of living Sea Elephants ; also a series 

 of skulls representing the principal genera of the Phocidaj, arranged ac- 

 cording to their structural affinities, the extremely long-skulled Sea 

 Leopards being at the left, I'hoca, of intermediate structure, near the 

 center, and Monachus and Mirounga, with widened skulls, at the right. 



