420 Dr. C. W. Andrews on some neio PJesiosauria 



Teeth long, slender, and very sharp-pointed ; anterior max- 

 illary teeth enlarged. Neck rather more than three times the 

 length of the skull and consisting of twenty-six vertebrae, 

 including the atlas and axis ; centra short, with strongly 

 concave articular ends, which are much wider than high. 

 The cervical ribs have a prominent anterior angle, which is 

 not, however, produced into a distinct process, as in the next 

 genus. The shoulder-girdle (fig. 1) is of Elasraosaurian 



Fijr. 2. 



Left fore paddle of Tricleidus seeleyi, sp. n., from above. (Tj^e specimen 

 R. 3539.) \ nat. size, a., accessory ossicle; h., humerus; int., 

 intermedium; l.}).. lateral process; m.c.v., fifth metacarpal; p., 

 pisiform ; r., radius ; 7-ad., radiale ; ti., ulna; uln., ulnare. 



type; there is a large interclavicle (^'.cZ.) and a pair of well- 

 developed elongated clavicles (cL). 



The humerus (fig. 2) is short and not greatly expanded 

 at its distal end, where it articulates with four bones, viz. the 

 radius, ulna, pisiform, and a small accessory postaxial ossicle 

 {a.), probably sometimes wanting. Femur more slender than 

 the humerus and articulating distally with two bones only. ■ 



