660 RECORDS. 



The physical conditions of the islands are touched on, and 

 the Crustacea are shown to be in the main similar to those found 

 in the West Indies and the adjacent coasts of America ; though 

 1 8 have a more or less extended range over both hemispheres. 



Professor Osborn reported upon the anatomy of the feet of a 

 specimen of the well known "mule-footed hog" of Texas, re- 

 cently presented to the Zoological Museum of Columbia by Dr. 

 Wickes Washburn. Externally the feet present the appearance 

 of complete fusion of the third and fourth toes. Internally, how- 

 ever, considerable differences are observed. In the pes, the third 

 and fourth metapodials and the first phalanges are entirely sep- 

 arated and normal, and the second pair of phalanges are closely 

 united and the terminal phalanx is also closely united, so it has 

 the appearance of a single element. The fusion is less advanced 

 in the manus ; here the metapodials, first and second phalanges 

 are separate, one of the second phalanges being abnormally 

 hypertrophied and a supernumerary element being inserted be- 

 neath it. The terminal phalanges are very firmly united into a 

 single element, which holds the bones above it together. 



Discussion followed, during the course of which. Professor Bris- 

 tol stated that a large number of experiments were being carried 

 on at a western ranch to ascertain the effects of breeding upon 

 this peculiar variety. Professor Osborn remarked that this 

 anomaly presented an interesting case of the persistence of a 

 character which must have originated as a sport. 



Professor Osborn 's second paper included a description of the 

 remarkable complete skeleton of a Mosasaur, recently mounted 

 in the American Museum of Natural History. The skeleton 

 was procured in 1897, from the famous Smoky Hill Cre- 

 taceous beds of Kansas, through Mr. Bourne and has been 

 worked out with the greatest care. It is practically complete as 

 far back as the 78th caudal, and the bones are approximately in 

 position, including the fore and hind paddle and, what is more 

 remarkable, almost complete cartilaginous sternum, sternal ribs 

 and epicoracoids. The species represents the largest type of 

 American Mosasaur, Tylosaiinis dyspclor Co'pe. As illustrated by 

 numerous photographs and drawings, the specimen throws a 



