268 SUPPLEMENT. 



R. 1668. The proximal portion of the right pectoral limb ; from the 

 {Fig.) Oxford Clay near Peterborough. These specimens com- 

 prise the humerus, radius, ulna, intermedium, and two 

 other small bones. The humerus with the radius and 

 ulna (fig. 62) are figured in the woodcut on the preceding 

 page. Presented by A. N. Leeds, Esq., 1889. 



Ophthalmosaurus pleydelli, Lydekker (n. sp.). 



Humerus shorter than in the preceding species, the postaxial facet 

 being relatively larger and wider, with a blunt and rounded termi- 

 nation, and the radial and ulnar facets also wider and shorter, the 

 latter having a rounded termination. Hindmost cervical vertebras 

 with a channel on the haemal surface. 



Fig. 63. 



Ophthalmosaurus pleydetti. — Eeversed view of the left humerus ; from the Kiine- 

 ridge Clay of Gillingham, Dorsetshire. J nat. size, a, trochanteric ridge ; 

 r, radial facet ; u, ulnar do. ; p, facet for pisiform. 



There is no decisive evidence to prove that this provisional species 

 is distinct from Ichthyosaurus (?) dilatatus (supra, ii. p. 30), but' 

 if the specimens there provisionally referred to that species are 



