ICHTHYOSAUEIDJ-;. 



25 



minal faces are nearly circular. Although of rather smaller 

 dimensions this specimen accords closely in serial position 

 and proportions with the one figured by Phillips, ojy. cit. 

 p. 336, diagram cxxvii. fig. 3. The vertical diameter is 

 0,U84, the transverse 0,084, and the length 0,040. 



Cunnington Collection. 



41776. The imperfect centrum of a larger middle dorsal vertebra ; 

 from the Kimeridge Clay of Weymouth, Dorsetshire. 



Purchased, 3 869. 



41776 d. The centrum of a rather smaller middle dorsal vertebra ; 

 from the Kimeridge Clay of Weymouth. Purchased, 1869. 



44599. A water-worn centrum of a very similar dorsal vertebra ; 

 from the Kimeridge Clay of Swindon. 



Presented by the Directors of the Swindon 

 Brick and Tile Company, 1873. 



47506. The centrum of a rather later dorsal vertebra, of consider- 

 able size : from the Kimeridge Clay of Kimeridge Bay, 

 Dorsetshire. 



Presented by J. C. Mansel-Pleydell, Esq., 1876. 



24684 c. A centrum agreeing in size with the preceding, but rather 

 later in the series, and of relatively greater length ; from 

 the Kimeridge Clay of Wootton-Eassett. 



Cunning ton Collection. Purchased, 1849. 



R. 271. The centrum of a middle dorsal vertebra of smaller size ; 

 from the Kimeridge Clay. Egerton Collection. 



R. 9. The centrum of an early posterior dorsal vertebra probably 

 {Pig.) belonging to this species; from the Kimeridge Clay of 

 Stanton, near 13ury-St.-Edmunds, Suffolk. In this speci- 

 men (fig. 13) the terminal faces are elongated transversely, 

 and not narrowed superiorly ; the vertical diameter being 

 0,111 (4*0 inches), and the transverse 0,128 (5*0 inches). 

 The costal tubercles are placed low and have nearly 

 coalesced. The difference in the contour of this specimen 

 compared with the next is parallelled in the vertebral column 

 of I. jplatyodon, No. 481 (p. 101), where tho centra marked 

 26 and 27 are of the contour of the present specimen, 

 while that marked 33 is of the type of the next specimen. 

 In the present specimen, however, the costal tubercles 

 have descended lower than in the corresponding vertebne 



