plesiosaumd^:. 193 



of No. 42496. The 22nd corresponds nearly to the one 

 marked 13 (42496 b) in No. 42496, which is" probably the 

 23rd of the full series. The present specimen differs from 

 the latter in the absence of the distinct lateral depression, 

 but has the same deeply enpped terminal faces, in which 

 the depression occupies the whole of the surface. The 

 posterior face has the same bevelled inferior border, but 

 the anterior face is slightly less elliptical. Compared with 

 No. B,. 1286 {infra), which is probably about the 20th of 

 the series, this specimen differs by the absence of the 

 lateral depression, and also by the circumstance that in 

 the terminal faces of the latter the depression is confined 

 to the central region ; both have the same approximation 

 to a circular form in the contour of the anterior face. 

 No. R. 1286 differs both from the present specimen and 

 No. 42496 6 in the bevelling of the lower border of the 

 anterior face, but in other respects is somewhat interme- 

 diate between the two ; its lateral depression being less 

 deep and more widely defined than in No. 42496 b. 



Made in the Museum, 1888. 



R. 1286. Cast of an imperfect middle (?20th) cervical vertebra. 

 The original is one of a series of cervicals obtained from 

 the Kimeridge Clay of Cumnor-Hurst, near Oxford, and 

 preserved in the Oxford Museum, that series being one of 

 the types of Plesiosaurus validus. The original of the 

 present specimen is figured on a scale of i, with consider- 

 able restoration, on p. 371 of Phillips's ' Geology of 

 Oxford ' : the rounded contour of the neural canal given 

 in the figure being due to an incorrect restoration of the 

 neural arch, which has now been placed in its proper 

 position. The chief characters of this specimen have been 

 already noticed under the preceding entry. 



Made in the Museum, 1888. 



31924. A large posterior cervical vertebra wanting the spine of the 

 neural arch and the extremities of the ribs ; from Shotovcr. 

 Length of centrum 0,054 (2-15 inches), height 0,078 (30 

 inches), width 0,099 (3-9 inches). This specimen closely 

 resembles the cervical figured by Phillips on p. 368. 



Pur cli used. 



31914. A rather smaller and somewhat earlier cervical vertebra; 

 from Shotover. The processes are imperfect. 



Purchased. 



PART II. O 



