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CIMOUOSAURUS RICHARDSON I. 



Cimoliosaunts ricJiardsoni. Ventral aspect of part of the right 

 pectoral limb ^ nat. size ; h, humerus ; tr, trochanter of ditto ; r, 

 radius ; u, ulna ; ?', radiale ; i, intermedium ; ^t', ulnare. 



The ulna and radius are short, the radial portion concave ; two 

 of the carpal bones are trigonal, the rest are polygonal. 



FEMUR. The articular surface of the femur is deeply pitted 

 and tuberculate. The proximal end is constricted below the head 

 before it begins to expand. Both margins are nearly straight and 

 gradually flatten out into a broad distal end. Length If in., 

 breadth 8in., 3f in. at the narrowest part of the shaft. The tibia 

 and fibula, and several of the carpal and phalangal bones, are well 

 preserved. 



Since this paper was read last autumn before the members of 

 the Club, the Plesiosauridve have undergone a complete revision 

 under the experienced - and critical eye of Mr. Lydekker, 

 F.G.S., to whom I am indebted for his valuable assistance in the 

 classification of this saurian. He refers Mi. Richardson's saurian 

 to the genus Cimoliosaurus, which he distinguishes from Plesiosaums 

 on account of structural differences, especially in the shoulder-girdle, 

 which are of so marked a character as to require a generic distinction. 



