RECORDS. 661 



flood of new light upon the structure of the Mosasaurs. The 

 principal characters are the following: J cervicals, lo dorsals 

 connected with the sternum by cartilaginous ribs, 12 dorsals 

 with floating ribs, i sacral and 72 caudals (out of a total num- 

 ber of 86) ; coracoids connected by broad epicoracoids having a 

 transverse diameter of 22 cm. The sternum is triangular in 

 shape tapering posteriorly and having the general form of that 

 in TracliydosmiriLs. There is no evidence of an episternum, the 

 shoulder girdle in general being more degenerate than Platacar- 

 piis, in which an episternum has been observed. The fore 

 paddles are smaller than the hind ones and include two coosified 

 carpals. The fifth digit is somewhat enlarged and set well apart 

 from the others. The hind paddle is slightly larger and very 

 completely preserved. The tail is remarkable in presenting an 

 upward curvature in the mid region, which probably supported 

 a prominent caudal fin, but it is not angulated as in IcJitliyosaiirits. 

 The skull shows the presence of epiptery golds. The total 

 length of the skeleton as preserved is a little over 27 feet, the 

 estimated total length of the animal is 30 feet. In mounting a 

 single large panel has been used, the animal lying upon its ven- 

 tral surface, w^ith the paddles outstretched, the sides of the back 

 bone curved in a graceful manner exactly as originally imbedded 

 in the matrix. 



Francis E. Lloyd, 



Secretary. 



SECTION OF GEOLOGY AND MINERALOGY. 



May 15, 1899. 



Section met at 8:15 P. M., Dr. A. A. Julien presiding. The 

 minutes of the last meeting of Section w^ere read and approved. 



The following program was then offered : 



Arthur Hollick, A Reconnoissance of the Elizabeth Is- 

 lands, Massachusetts. 



W. Goold Levison, Notes on : (i) Photographs of Min- 

 erals FOR Illustrating Books and Lectures. 



