CETIOSAURID^]. 139 



Cetiosaurus brevis, Owen *. 



Imperfectly known, and provisionally referred to this genus. 

 Chevrons always open superiorly ; first sacral vertebra with lateral 

 pits ; four vertebrae in sacrum. 



Mantell identified this form with Pelorosaurus ; and Seeley, who 

 adopts the same view, regards both as referable to Ornitliopsis. 

 The anterior caudal vertebrae of the present form resemble those of 

 C. oxoniensis in the broad, angulated faces of their centra and open 

 chevrons, and thereby differ from those of Brontosaurus, while the 

 sacrum differs from that of both the latter and Ornitliopsis. If the 

 elongated cervical vertebra?, mentioned on p. 142, belong to this 

 form, its distinction from Ornitliopsis will be still more closely 

 marked ; while if the fore limb, mentioned on the same page, be 

 referable to it, there will be a probability of its distinction from 

 Cetiosaurus. 



Hah. Europe (England). 



All the following specimens are from the Wealden. 



2249. One imperfect extremity of a dorsal vertebra, probably be- 

 longing to this form : from Cuckfield, Sussex. The 

 inferior and one lateral surface, together with the floor of 

 one of the lateral vacuities, are shown. This bone is 

 smaller and narrower inferiorly than the vertebrae of 

 Ornitliopsis, and in this respect comes nearer to the 

 smaller undetermined vertebra, No. 2239 (p. 142). 



Mantell Collection. Purchased, 1828. 



36559. The centrum of the last lumbar vertebra anchylosed to 

 the anterior half of that of the first sacral ; from Brook. 

 The lumbar vertebra shows small lateral pits descending 

 obliquely towards the middle of the centrum. The sacral 

 as well as the following specimens from the same part are 

 completely solid. Noticed, together with the following 

 specimens, by the writer in the ' Quart. Journ. Geol. Soc/ 

 vol. xliv. p. 56. The lumbar vertebra differs consider- 

 ably from that of Ornitliopsis (No. E. 209). 



Hastings Collection. Purchased, 1855. 



36559 a. Portions of the centra of the second and third sacral 

 vertebrae, associated with the preceding. Same history. 



1 Rep. Brit. Assoc, for 1841, p. 04 (1842). 



