PELONEUSTES EVANSI. 75 



47837. Plaster cast of the imperfect atlas and axis of the type specimen ; described and fignred 

 by Seeley in Quart. Journ. Geol. Soc. vol. xxxiii. (1877) p. 717, figs. 1 & 2. The 

 original, in the Sedgwick Museum, Cambridge, is from the Oxford Clay of St. Xeots. 

 The dimensions (in centimetres) of this specimen are : — 



Length of the centra of atlas and axis and anterior wedge-bone . 9-7 

 Combined length of the neural surfaces of the atlas aud axis. . 84 

 Width of posterior face of axis (approx.) 7 - 9 



Presented hy Prof. II. G. Seeley, F.R.S., 1876. 



E. 1713, E. 1713 a. Plaster casts of the centra of the fourth and fifteenth cervical vertebrEe of the 

 type specimen ; described and the fourth vertebra figured by Seeley in Quart. Journ. 

 Geol. Soc. vol. xxxiii. (1877) pp. 718-9, figs. 3 & 4. These figures reproduced by 

 Lydekker in Catal. Foss. Eept. Brit. Mus. pt. ii. (1889) p. 129, fig. 39. The originals 

 in the Sedgwick Museum, Cambridge, are from the Oxford Clay of St. Neots. 

 The dimensions (in centimetres) of these centra are : — ■ 



Fourth. Fifteenth. 



Length in mid-ventral line 4 (approx.) 4"5 



Width of articular face 7"5 S-9 



Height of articular face 6-5 7 - 6 



Made in the Museum. 



E. 2443 (Leeds Coll.). Mandible and hind paddles (except femur) of a large individual. The mandible 

 is larger than any other jaw of Peloneustes in the Collection ; it differs from the others 

 also in having only twelve teeth on each side of the symphysis, which is only slightly 

 expanded, and the length of which is less than a quarter of the total length of the jaw. 

 instead of about a third as in Peloneustes philarchus. On account of these differences from 

 the last-mentioned species, these specimens are here provisionally referred to P. evansi, 

 as suggested by Lydekker. The mandible is figured by Phillips in the ' Geology of 

 Oxford' (1871) p. 318, fig, 122, as Pliosaurus ? grandis. The hind paddle, which 

 presents no important peculiarities, is figured by the same author {torn. cit. p. 317, 

 fig. 121), but the femur shown in the figure is certainly not that of Peloneustes and 

 probably belongs to a Cryptocleidus. 



Some dimensions (in centimetres) of these specimens are : — 



Mandible (text-fig. 27, B) : extreme length 115-0 



length of symphysis 25*4 



greatest width of symphysis 8*6 



length of postarticular process S - 3 



Hind paddle : 



Tibia: length of preaxial border 13"1 



greatest width 11*7 



Fibula : length 12-2 



width 11-6 



E. 3891 (Leeds Coll.) . A large part of the skeleton, including the skull, mandible, atlas and axis, and 

 sixteen other cervical vertebra, thirty pectorals, dorsals and (?) sacrals, sixteen caudal-. 



L2 



