MR. T. ATTHEY ON ANTHRACOSAURUS RT7SSELLI. 325 



borders of their posterior surfaces project in a similar form 

 downwards. The sides of the bodies are level with each other : 

 no facet is visible on the sides of the vertebral bodies for the 

 articulation of the heads of ribs ; but the facet on the transverse 

 process is distinct and large, but is not divisible into an upper 

 and a lower part. The neural canal is remarkably small for the 

 size of the vertebra. The transverse and zygomatic processes 

 and the spinous processes arise, in the specimen figured, from 

 the sides and top of the arch ; they are all massive and of consi- 

 derable size ; the transverse processes have a length of one inch 

 and a half, a breadth of nine-tenths of an inch, and a thickness 

 of two-tenths of an inch. The direction of the transverse process 

 is almost directly outwards ; that of the anterior pair of zyga- 

 pophyses, which are rather concave, is upwards and slightly 

 inwards; the posterior face downwards and outwards, and are 

 somewhat smaller than the anterior pair. 



The measurements of the small dorsal vertebra (Plate VIII., 

 fig. 4) are as follows (in inches) : — 



inch. 



Heightof body 1*6 



Transverse diameter of body 1*6 



Length of body O'G 



Height of neural arch 0*3 



Height of spinous process from top of neural arch to apex 2*3 



Length of ditto 0-6 



Thickness of ditto 0*3 



Width of transverse process 0*6 



Thickness of ditto 0*2 



Length of ditto 1*2 



The spinous process projects directly upwards and is very thick 

 and strong and somewhat enlarged near the extremity, which is 

 pointed. 



Bibs. — Upwards of twenty ribs were found associated with 

 the skull and vertebras ; a great many of these are perfect. The 

 largest is nine inches long, by a little more than half an inch in 

 breadth, and is well and regularly arched. The curve of the 

 bone is continued as far as the head, which ends in a concave, 

 transversely oval, undivided, articular surface ; the tubercle is 



