312 RECORDS. 



disintegration theory of radio-active change, the discovery of 

 Curie in regard to the heating effect of radium, and the experi- 

 ments of Ramsay and Soddy bearing on the question of the con- 

 tinuous production of heHum in radium compounds. An ap- 

 paratus was exhibited hke that of Mr. Strutt, to show by the 

 akernate charging and discharging of an electroscope the pro- 

 duction of electric charges by radium. The charging of the 

 gold leaf in the apparatus shown by Dr. Pegram took place in 

 about one minute. Charles C. Trowbridge, 



Secretary. 



SECTION OF BIOLOGY. 



February S, 1904. 



Section met at 8:15 P. M., Vice-President Underwood pre- 

 siding. The minutes of the last meeting of the Section were 

 read and approved. 



The following program was then offered : 



0. P. Hay, A New Gigantic Tortoise from the Miocene 

 OF Colorado. 



F. E. Lloyd, The Flora of Dominica. 



Summary of Papers. 



Dr. Hay described a tortoise that was discovered during the 

 year 1901 by Mr. Barnum Brown, of the American Museum of 

 Natural History, in the Pawnee beds of the Miocene, in the 

 northeastern part of Colorado. The remains consist of the shell 

 complete ; the skull, lacking the lower jaw ; the pelvis and 

 hind limbs ; the terminal portion of the tail ; and portions of 

 the dermal armor. These materials were exhibited before the 

 academy. 



The length of the carapace is about 3 1 inches. It is high 

 and tumid, with the sides at the bridge perpendicular, and with 

 the hinder border little flaring. The outline is truncated in front, 

 broadly rounded behind, and only slightly repand. The free 

 edges are acute. The bridge peripherals rise somewhat above 

 the middle of the height of the shell, their length transversely 



