SMITIISOXIAN MISCELLA.XEOUS COLLECTIONS 



VOL. 'Jl 



Txlosaiinis was a loiii;', sleiider-bodicd re])tile some 25 feet in 

 lent^th, having" the limbs nioditied into short swimmini^' ])a(ldles. with 

 a long, powerful. com])ressed tail. It was ])redatory in habits, living 

 on tishes and probably also on the smaller individuals of its own kind. 

 One of the uni(|ue features of the skeletal structure is the ])resence 

 near the middle of the lower jaw of a joint which permits it to bow 

 outward. This feature in connection with the loose articulation at 

 the extrenn'ties allowed the jaws to expand and thus enal)led the 



Fig. 



;i. — 1 lie swimming reptile Tylosaunis dyspclor in process of 

 preparation for exhiljition. Photograph by Bassler. 



animal to swallow large objects. In life the body w-as covered by 

 small horny scales. A stud\- of this specimen is being made by 

 Mr. C. ^^^ Gilmore. and the results of his investigations will be ]Hib- 

 lished in the Proceedings of the U. S. National ^Museum. 



In figitre 22 is shown another of the recently mounted skeletons — 

 that of the large extinct Rhinoceros-like mammal from the Tertiary 

 ( Oligocene) deposits of western Nebraska, named by (Jsborn Bron- 

 tothcriiim hatchcri. The bones of this skeleton were found em- 



