104 Prof. H. G. Seeley on the 



present in abeyance, though the specimens exist on whicli 

 definitions might be based. 



Vertebral Column. 



Few vertebras were collected ; they represent the cervical, 

 dorsal, sacral, and caudal regions. Since the bones belong to 

 two or three individuals of different sizes, caution is necessary 

 in using them as evidence for the reconstruction of the form 

 and proportions of the animal. The cervical vertebrae are 

 most elongated; but the dorsal vertebrje are more compressed 

 from side to side than the cervical at the articular ends, 

 and they have the centrum shorter. The single sacral 

 centrum is shorter than the dorsal and has the body of the 

 vertebra more depressed. The caudal vertebrge, on the other 

 hand, are longer than the sacral, have larger articular faces 

 than the dorsal, and carry chevron-bones. 



Cervical Vertehrce. (Fig. 1.) 



The specimen numbered 331 (fig. 1) was regarded as a 

 vertebra probably from the tail ; I interpret it as cervical. 

 Compared with the figure of the cervical vertebra of Zanclodon'^ 

 it is seen to be almost identical in plan, the obvious difference 

 being that the neural spine is a little more posterior in position 

 in Massospondylus and that the transverse plate, extending 

 outward like a film, which makes the upper tubercular articu- 

 lation for the rib, has a more posterior position. 



Fig. 1. 



Left side of a cervical vertebra. About I nat. size. No. 331. 



The aspect of the vertebra is somewhat elongated, with a 

 strong low neural spine, strong zygapophyses (low in position 

 and deeply cleft), with the centrum compressed from side to 



* * Popu ar Science Review,' n. s. yol. iv. pi. ii, fig. 3, 



