and satjkopxerygians of the purbeck etc. 53 



Discussion. 



The Peesident regretted the absence of those best acquainted 

 with the subject, and alluded to the difficulties in the way of 

 criticism. 



Mr. Leeds, reiprring to the fossil from the Oxford Clay, observed 

 that the jaw is identical with Fliosaarus and the paddle with 

 PdoneiiHtes. He was in possession of a large jaw of Pliosauru.s'^ 

 measuring 4 ft. 7 in., with which he identified the lower jaw of 

 this species. The body-bones were much broken np. There was 

 great ditference in the size of the paddles, but he did not know 

 whether the fore or hind paddles were the larger. 



Mr. E. T. Newton was satisfied, with regard to the specimens of 

 lyuaaodoii referred to, that the species were distinct. 



Dr. Woodward spoke of thanks being due to Mr. Leeds for the 

 c&,re with which he had worked the clay-pits of the country round 

 Peterborough. In this country remains of Saurians were too often 

 fragmentary, whilst in Belgium they were often entire. Mr. Leeds 

 had secured complete remains of Oxford and Kimeridge Clay marine 

 reptiles, and had taken care to match the individual bones with the 

 individual specimens. 



He also spoke of the good work of Mr. Dawson amongst the 

 Wealden Dinosaurs, and of Mr. Rufford as regards the vertebra of 

 Ljuanodon, 



Prof. Hughes inquired as to the evidence for the association of 

 the bones referred to the same individuals. 



Mr. Leeds explained that some of his specimens consisted of the 

 entire skeleton, whilst others were imperfect. These particular 

 bones were much broken, but were all found on one level ; had it 

 been otherwise he would not have connected them. He proceeded 

 to describe the position of the bones, which were certainly those of 

 one animal, there being none other. 



Dr. MuEiE, alluding more especially to Ljuanodon, spoke of the 

 difficulty of judging from diagrams in the absence of the specimens. 

 Looking at the femurs, one might say that the difference was one of 

 age rather than of species. 



Mr. Smith Woodward thought that Peloneustes should be rede- 

 fined or done away with. With regard to the skeletons obtained 

 by Mr. Leeds, there could be no doubt as to the natural association 

 of the bones ; they rested upon well-defined old floors in the clay, 

 marked by accumulations of broken shells. 



The Author, in reply, stated that he had given his reasons for 

 regarding the Iguanodont remains as associated; there was no 

 (|uestion whatever as to those of the Pliosaurian belonging to a 

 single individual. He could not admit Dr. Murie's view that the 

 differences in the Iguanodont remains were due to age. In reply 

 to Mr. 8mith Woodward, the Author remarked that Feloneusfex was 

 distinguished from Pliosaurus by its cervical vertebra) as well as by 

 the longer mandibular symphysis. He acknowledged his obligations 

 to Mr. Leed^ and Mr. Dawson. 



