THE FOREST-BED OF EAST ANGLIA. 101 
rudimentary neural spine is at the middle of the upper surface in the former, and in 
front of the middle in the latter. The dorsal nerve-foramina of C. giganteus are 
constricted into a figure-of-8 shape (and completely divided by a bridge in a specimen 
from the Barrington gravel in the Woodwardian collection), while they are long slits 
in C. belgrandi. Vhe neural arch of C. belgrandi has a wider sinus behind on its dorsal 
side ; its anterior dorsal emargination is more square-cut: the ventral depression behind 
the nerve-foramen is much deeper; the hypapophysis is most prominent behind, with a 
median ridge passing towards the anterior end of the vertebra (that of the Woodwardian 
specimen of C. giganteus having no ridge). In some of these latter points the Barrington 
specimen holds an intermediate position between the two others. 
In the Axis:—The dorsal edge of the neural spine is thinner in C. belgrandi; the 
transverse processes, which are incomplete, were probably less projecting ; the posterior 
zygapophyses are narrower (1°05 inches, as compared with 1:5-1°8 inches) and more 
raised; there is a distinct emargination between the pesterior zygapophysis and the 
neural spine; and the ventral median ridge is distinctly higher and bounded by 
deeper grooves at its sides than in C. giganteus. 
In the tables which follow, the measurements have been taken in such a way as to 
permit of easy comparison with those give 7m Boyd Dawkins ', Belgrand?, and others. 
I. SKULL. 
inches. | millim. 
Greatest length of the part of the skull preserved .................- = SHY) 228 
Greatestvbreadth other skull vary ereteletete eiusiays)aiereioleste s| cele) eieolal isle «J $1 206 
Occipital crest to fronto-parietal suture ........ 06.605. e eee eee eee +1 104 
i - pedicle (shortest distance) ........--.--+-++++.+---. 30 76 
Interval between pedicles ........ sees ee ee nee ee eee e tet eneee 30 76 
A Fs supra-orbital foramina 0... 1. eee ee ee ee eee eee 39 99 
From burr to burr (shortest distance)... ...... 0c ee ee eee eee ees 5-4 137 
es op (distance between outer edges)................-..- 10°4 265 
Top of foramen magnum to top of occipital crest ...-........-.+. 00s 3:0 76 
Foramen magnum, height of ........-. eee eee eee e recente eens 11 28 
PA rr VAC ULE OL: charm snesNeisr ab samror ed sreke) atch stot vale! of aust ah ol hatch sLatel ais 1-4 35 
Frontal width, just below pedicles ......-. ses. seer eee e eee eens 73 185 
Pedicle, length of... 1.2... ce ue vartee ee ctor ties cree vein veeceeeees 18 46 
» circumference Of ...... 6.60 ee even ee ‘SEED OS OUR Docc 8:5 215 
» antero-posterior diameter Of 6... .. see see e vere ee eee n ee eee ee 61 
,»  dorso-ventral diameter Of ©. 0.6... se cece ee eee eee eee nee 2-9 7+ 
Interval between bases of R. & L. brow-tines .... 2... cee eee seen eee 9:8 250 
Brain-case, diameter (external) behind pedicles.........++++ee+eeeee- +6 117 
Distance between outer edges of condyles .......--+ 00s eee ee ee ee eens 3:8 97 
1 Pal. Soc., t. cit. pp. 25-28. 
2 « La Seine.—I. Le Bassin Parisien. Planches de Paléont.,” 1869, p, 13. 
