_ from the Shales of the Northumberland Coal-field. 273 
all the processes can be determined more or less completely. 
They were found at Newsham, but at different times. These 
very interesting relics closely resemble the figure of the ver- 
tebra of Anthracosaurus given by Prof. Huxley in the ‘Journal 
of the Geological Society ’ (1863, vol. xix. p. 63). Our speci- 
mens, however, are larger, the neural arch differs a little in 
form, and there is a very minute notochordal foramen. 
The body or centrum is biconcave, and appears to be con- 
siderably flattened lengthwise. The margins of the articular 
surfaces are reflected, so that in section the faces of the body 
would present a sigmoid curve from the centre to the margin. 
The height is a little more than the breadth, and the circum- 
ference at the sides and below is well rounded, though there 
is here and there a tendency to angularity ; but whether this 
arises from original conformation or from accidental and un- 
equal reflection of the margin, cannot be determined. ‘The 
upper margin of the anterior face is produced a little in the 
centre, forming a rounded elevation immediately below the 
neural arch, and is angulated at the flanks. The same region 
in the posterior face presents a shallow concavity, exactly 
similar to that represented in Prof. Huxley’s figure referred to. 
The sides of the body are somewhat concave, and transversely 
wrinkled or coarsely striated. ‘The minute notochordal fora- 
men, which is only large enough to admit a stout knitting- 
needle, is difficult to determine, though there can be no doubt 
of its existence. 
The neural arch is comparatively small; it is oval, the long 
axis being perpendicular ; the lips of the arch are produced a 
little in front ; behind they do not appear to be so. The walls 
of the arch are very stout, and pass upwards to form a lon 
high spinous process, which is nearly as high as the centrum, 
and is thin, being much compressed laterally. 
The anterior zygapophyses are large ; their articular surfaces 
are hollow and elongated transversely ; their inner borders are 
confluent. ‘The posterior pair are much distorted; but they 
ppear to form wide, transverse articular surfaces, the faces of 
which look downwards. fee 
The transverse processes are perfect in neither vertebra, 
though in one of them the extremities only are lost; they are 
broad and much compressed from front to back, and originate 
apparently in the ‘aes of the neural arch and the upper sur- 
face of the centrum. They project almost horizontally ; but 
so much of their extremities is wanting that there is no dis- 
tinct evidence that they are divisible into an upper and a 
lower oho an pam to the head and tubercle of the 
rib. ‘The upper portion, however, is thicker than the lower. 
