220 ON PATRICOSATJRTJS MEROCRATUS FROM CAMBRIDGE GEEENSAJND. 



Prof. Seelet said that out of many thousands of hones from the 

 Cambridge Greensand that had passed through his hands these were 

 the only fragments of Lizards. He thought no others were likely 

 to be found for some time, aud there was little chance of any re- 

 mains of two Lizards occurring. If, however, one bone were to be 

 selected as the type, he would take the femur, to which the specific 

 name referred. 



With regard to OrnitJiodesmus, he said that it differs from all 

 Ornithosaurs in having a horizontal neural platform running through 

 the sacrum, and from which a continuous neural spinous ridge rises. 

 The transverse processes and pneumatic foramina did not tend to 

 approximate the two groups ; while, so far as he was aware, the 

 Wealden Ornithosaurs had the ventral side of the sacrum much 

 more convex from side to side. He further pointed out that the 

 texture and form of the sacral vertebrae differed from those of known 

 Pterodactyles. 



