AND AVES OF NORTH AMERICA. GO- A 



From the above, four points may be derived: 1. That the ribs are continued to the sacrum in this type, a char- 

 acter not before pointed out among its representatives in this country or Europe, and one in which it differs from the 

 Crocodilia from the Cretaceous to the present period inclusive. 2. That the sacral diapophyses articulate with two 

 vertebras instead of one, a point similarly exceptional with the last point. 3d. That in both these points this type 

 approaches the Dicynodontia and Dinosauria, as it does in some others. 4th. That the B. lepturus belongs to a dif- 

 ferent species' from that from N. Carolina, last described, in having at least three diapophyses witli double articulation 

 near the extremity instead of one, and to a different genus from the same, because several of these are cylindric in the 

 former, and broadly flattened in the latter. 



"Which genus is distinct from Belodou is difficult to ascertain. If we suppose B. carolinensis to represent it, as it 

 certainly does in cranial characters and other respects, the North Carolina specimen will represent another genu-, 

 since a sacral vertebra of B. carolinensis presents all the characters of that of B. lepturus. 



The centra of the vertebras are very much compressed, and the articular faces flared out at the margins. The 

 faces are wide vertical ovals and distinctly concave. The posterior face of the supposed last dorsal is flattened, and 

 presents two slightly swollen triangular planes, each from the facet of the margin. 



The neural spines of the anterior vertebras are shorter and wider, of the posterior more elevated and narrower. 

 The rib supporting the anterior zygapophysis is very prominent in all, as is that defining the margin of the neural 

 arch. They include a short vertical concavity between them, giving the vertebrae a marked character. 



The eaudals are very much compressed, more so than in B. ?priscus, though since they are median in the series. 

 and those of the latter are proximal, there would probably be a greater resemblance between the homologous ones. 

 The articular extremities are vertically oval, and but little flared at the margins. The neural arch with its apophyses 

 is compressed. The diapophyses project just below the base of the arch, and are depressed and stout. 



Measurements. IT. 



Vertebra 1st type, 0.18 



Do. height neural spine from canal, 0.10 



Do. length diapophysis, 0.026 



Do. " centrum, 0.05 



Do. diameter centrum .middle, O.021 



Do. " " articular face, 0.055 



Do. " " vertical, articular face, O.059 



Total elevation type 2d, 0.1951 



Do. neural spine from canal, 0.122 



Do. width do., 0.04 



Do. length centrum, 0.05 



Do. diameter (transverse) centrum middle, 0.023 



Do. " " " artic. face, 0.054 



Do. " vertical " " 0.06 



Do. elevation type 3d, 0.186 



Do. neural spine from canal, 0.11 



Do. length centrum, 0.049 



Do. diam. (transverse) centrum at middle, 0.032 



Do. " " " artic. face, 0.061 



Do. " vertical " " 0.062 



Do. expanse anterior zygapophyses, 0.07 



Do. diameter neural canal, 0.02 



Length diapophysis, 0.082 

 The neural canal in the vertebra first described, is narrower and more elevated than in the last dorsal. 

 A chevron bone has nearly cylindric limbs and short common junction of the same. Their proximal extremities 

 are considerably expanded, but not so as to meet on the median line. They are very oblique backwards and inwards. 

 Distal extremity strongly striate. 



