634 PROF. H. G. SEELEY ON THE DINOSAURIA OF 
terior articulation; it has no trace of a neural spine or lateral 
process. 
The fourth vertebra is much smaller and more constricted. It is 
fully 2 inches long. The transverse measurement in the posterior 
articulation is 1,4, inch, while the depth is about an inch. The 
outline is subtriangular, and the cup is deeply excavated. There 
appears to be only one chevron facet; and, though larger poste- 
riorly, a similar small facet also impresses the anterior articulation. 
This surface is flat, broadest in the upper part, but not so deep as 
broad. The least transverse measurement in the middle of the cen- 
trum is 1 inch. A median lateral ridge on the side of the centrum 
is well marked; above it the side of the centrum is concave in both 
measurements ; below it the side of the centrum is convex vertically 
in the middle part. The neural arch is very small,’and is margined at 
its base by ridges, which appear to mark its junction with the cen- 
trum. The vertical measurement through the vertebra from the 
neural canal to the base is 55, inch just behind the neural arch. 
The fifth vertebra is 1,5, inch long, and distorted by the develop- 
ment of the chevron element only on the left side. Normally, the 
centrum would be hexagonal, with a median longitudinal ridge on 
the side. The width in front, about 154, inch, is considerably more 
than the depth; posteriorly the measurements are less. The neural 
arch is small and compressed, with its upper margin horizontal. 
The sixth vertebra is as long as the fifth, and has the facet for the 
hypapophysis developed in front and behind; but the ridges are 
absent from the middle of the underside of the centrum. The lateral 
ridges, on the other hand, are greatly developed and nearly parallel 
to each other; this gives the centrum a depressed appearance. The 
anterior articular face is the wider, while the posterior face is the 
deeper, being more than 55, inch deep, the anterior face being fully 
38; The neural canal is still about 7 inch wide. 
Conclusions concerning the classification and organization of these 
Dinosaurs may conveniently be deferred until the whole of the 
remains have been described and figured; but these and other 
studies strongly enforce a conviction that the Dinosauria are far more 
nearly related to the Triassic and older Secondary Crocodilia than 
the evidence of their affinities hitherto adduced would have pre- 
pared us to anticipate. 
EXPLANATION OF THE PLATES. 
All the figures are of the natural size. 
Pratt XXXIV. 
The vertebral column of Anoplosaurus curtonotus, 
Fig. 1. Left lateral aspect of third to seventh cervical centrums, showing how 
the bodies of the vertebrae increase in depth from before backward, 
and indicating at the upper anterior corner of each an attachment 
for a cervical rib. 
1 a. Visceral aspect of third (?) cervical vertebra, showing flattened and 
rounded under surface, and expansion towards the anterior end. 
