192 GEOLOGY. 



Cope. A few years ago a magnificent specimen of what I take 

 to be this reptile, judging from a photograph submitted to me, was 

 found in Dixon County, at the edge of the Missouri bluffs. Un- 

 fortunately, it fell into the hands of men who cared more for money 

 than for science. They attempted to make money by exhibiting 

 it, and after this proved a failure, gave it away partly by piece 

 meal. 



A species similar to the last, and also described: by Cope, was the 

 polycotylus latipinnis. It was extraordinary for the length of its 

 neck and attenuated head, though its tail was short and massive, 

 doubtless to balance its long neck while moving through the water 

 and capturing its prey. It was a powerful swimmer, as is evident 

 from its two pairs of paddles, four feet long, with a lateral expanse 

 of from eleven to twelve feet. The bones of a reptile found near 



/ Sheridan, Kansas, has been referred to the genus Plesiosaurus, of 

 .. -s which there have been found and described the remains of many 



7 species in the European chalk. The two preceding and this last 

 (Plesiosaurus gulo) are the only ones in this large family of Saurop- 

 tergia that have yet been found in the Cretaceous in the West. This 

 is evidently, as Cope has remarked, because of the presence of an- 

 other order, almost entirely absent in Europe, but the real rulers of 

 our Cretaceous seas the Pythonomorphs or Mososaurs of Leidy- 

 These reptiles had characters that related them to the lizards and 

 serpents, and in the absence of a sternum, to tortoises and plesio- 

 saurs. They pre-eminently characterized the cretaceous seas oT 

 America, being found in the deposits of this age in Alabama, New 

 Jersey, and especially in Kansas and Nebraska. One-half of all 

 ir the reptiles found here belong to this order, but only four species 

 V have yet been found in Europe. 



It was Cope who first made known the wonderful forms of these 

 reptiles, especially the mouth parts. Their form was very much 

 elongated, especially the tail. The head was long, conical and flat, 

 with the eyes directed upward and forward. As in snakes, the roof 

 of their mouth was furnished with four rows of conical large teeth, 

 which were not structured for masticating, but for seizing their prey. 

 The structure of their jaws was unique among animals. Though 

 they swallowed their prey whole, like snakes, they were without 

 their expansability of throat, which is due to an arrangement of 

 muscular levers "supporting the lower jaw." They were, how- 

 ever, furnished with an additional joint in each side of this organ, 



