390 THE PORTLAND OOLITE PERIOD. CHAP. 



CETEOSAURUS LONGUS. 



A caudal vertebra from the Portland stone at Garsington, near 

 Oxford ; length, 7*0 inches ; transverse diameter, 7-9 ; vertical 

 diameter, 6*0. Both articular faces slightly concave ; body slightly 

 compressed laterally, so as in the middle to give a subquadrate ver- 

 tical section, with the angles slightly rounded ; the expanded 

 articular ends subcircular. 



A fractured dorsal or lumbar vertebra, from the same locality, 

 with transverse processes extending obliquely backwards from the 

 upper part of the sides of the body, measures one foot across the 

 nearly flat articular surface. 



A caudal of the same species, from the Portland stone at Thame, 

 measures 7*4 inches in length; 6*6 in transverse diameter; and 7*8 

 in vertical diameter. The under surface is concave lengthways, 

 and it is nearly flat from side to side ; it is perforated by many 

 large vascular canals. 



A third caudal is somewhat shorter, but not less than 8 inches 

 in height. 



In all these vertebrae the neurapophyses are anchylosed to the 

 centrum, and have a smaller antero-posterior extent at their base 

 than the centrum. 



These notices of specimens in the Bucklandian Museum are 

 taken from Professor Owen's report to the British Association, 1841. 

 "We possess at present only two of them, the first and third men- 

 tioned. 



It is by no means certain that they are congeneric with 

 Ceteosaurus Oxoniensis. Had dorsal vertebrae beeu obtained shew- 

 ing the very deep lateral depression (Diagrams LXXXVIL, 

 LXXXVIII.) which in some crushed examples seems almost to 

 become a transverse perforation under the neural canal, or had the 

 neuro-spine been preserved, with a clavate head, we might have 

 boldly ranked these Portland fossils with those of the Bath oolite. 

 But the caudal vertebras in our possession do not furnish sufficient 

 evidence. 



MEGALOSAURUS BUCKLANDI. 



The reason for admitting this great reptile into the catalogue 

 of fossils of this age, is the discovery of three metatarsal bones, 



