from the O.r/onl Chiy of Peterborouf/h. \2'.\ 



(lescilhod and fi;^uit'(l hy Siudey in the Pioc. Roy. Soc. 

 vol. li. (l.^l>2) pp. 142-14"), fi;,'.s. 10-12, as AfurcBnosaurua 

 beloclis. Ill atiditioM to Soeley's typo speciinon (R. IDG/i) 

 the collection includes a second, which in many respects 

 8upj)Iement3 the other — portions ot* the skull, the anterior 

 portion of the cervical region of the vertebral column with 

 arches and ribs, a number of caudal vertebrae, and parts of a 

 hind paddle being preserved. 



The dimensions (in centimetres) of the type specimen 

 (R. 196.5) are :— 



Posterior cervical vertebra : 



I.enp-th of centrum 3*2 



Wilth „ 40 



Height ,, 3 (app.) 



Ileijrlit to top of neural spine l2'o 



Shoulder-girdle : greatest length 382 



Coracoid : 



Lenprth 277 



Width of united coracoids at binder angle of 



glenoid cavity 27*8 



Width at postero-extemal angles 234 



Interclavicle : 



Length 7-0 



Width 3-8 



Humerus : 



Length 18-3 



Width of distal expansion 9'9 



Fum. Pliosauridae. 



As mentio?ied above, this family is represented in the 

 Oxford Clay by the genera Pliosaurus and Pelonexistes and 

 by a new form in which the snout is much less elongated 

 than in the other two. It is possible that tliis animal may 

 be nearly related to Thaumatosaurus of von Meyer *, a genus 

 known only from a few fragments of tiie skeleton from the 

 Lower Oolite of Wiirtemberg. Thaumatosaurus was redefined 

 by Mr. Lydekkerf, but it is almost certain that several of 

 the species, particularly those from the Lias, which he included 

 in it, are generically distinct, and the animal now under 

 consideration does not fall within his detinition. On the 

 whole, therefore, it seems well to establish a new genus for 

 this species, particularly as nearly the whole of the skeleton 



• Neues Jahrb. f. Min. 1841, p. ITt) ; also * Palteontographica,' vol. vi. 

 (18'><5-8) p. 14. pl.o. iv. & v. 



t Cat. Foss. Kept. Brit. Mus. pt. ii. (l>^«<n) p. 1.58. 



