316 THE OXFORD OOLITE PERIOD. CHAP. 



The femur is 16 inches long, and nj broad at the distal end. 

 The two bones, which correspond to tibia and fibula, are 8 and 4/5 

 broad, while the tarsal bones together measure only 7*5 inches across. 



Professor Owen observed this valuable specimen in the Wood- 

 wardian Museum at Cambridge, and places it near to Plesiosaurus 

 doedicomus, which has a femur expanded in the distal region; the 

 expansion is, however, greater in this Bedford specimen. The 

 proximal end shews no tuberosity ; the distal ends have only two 

 broadly sub-articulating faces, to fit with the remarkable tibia and 

 fibula. The metatarsal row of bones has proximal facets of different 

 forms to fit the tarsals. The phalangal bones are thick and solid ; 

 the five rows can be recognized, the largest bones being those of the 

 fourth toe. The largest phalanx is 3*2 inches long, and 17 broad. 



Taking the length of the femur, 100 inches, the breadth is 70, 

 the whole paddle 287, the part beyond the femur 187. 



PLESIOSAUKUS TKOCHANTEKIUS. Owen. 1839. 

 (Referred to Pleiosawrus in 1841.) 



A fine femur of this species, in the collection of the Earl of 

 Enniskillen, was, he informs me, obtained from the Oxford clay 

 at Christian-Malford b . A cast of it is in the Oxford Museum. 

 The species occurs more abundantly in the Kimmeridge clay, and 

 there are points regarding it which will be better discussed under 

 that title. 



PLEIOSAURUS. 



Specimens of unconnected dorsal vertebrse have been occasionally 

 brought by workmen reporting them to have been found in the 

 Oxford clay pits, which have a decided pleiosaurian character, and 

 correspond very much with specimens from Weymouth, and with 

 others from Shotover. The small distance between the pits in the 

 Kimmeridge and the Oxford clay in the vicinity of Heddington 

 and Oxford, made me hesitate to admit these vertebrae as being 

 truly from the lower deposit. But I am now satisfied. The species 

 will be described under Kimmeridge clay. 



A distinctly pleiosaurian cervical vertebra, with cicatrices of the 



b In Professor Owen's Report on Fossil Reptiles, 1839, this bone is said to have 

 been from the Kimmeridge clay of Shotover Hill, where indeed others like it in many 

 respects are found. 



