622 PROF. H. G. SEELEY ON THE DINOSAURIA OF 
appear to have been symmetrical and median, others to have been 
placed laterally. Each plate has a sharp elevated ridge. But 
there is no positive evidence that the armour was found with the 
bones. The circumstance was not stated when the collection was 
purchased by the University ; but after the remains were exhibited 
in the Woodwardian Museum, Mr. W. Farren mentioned to me 
that both sets of bones came to him at the same time and from the 
same washing, and might therefore perhaps have been associated 
portions of one animal. This species was indicated in my ‘ Index’ 
1869, pp. xvu & 24, as Acanthopholis macrocercus. 
Thé Vertebral Column.—The vertebral column steadily enlarges 
from the neck to the lower part of the back. In the earlier dorsal 
region the articular faces of the centrums are slightly concave ; but 
* in the lower part of the back they are flat at both ends. In the 
early part of the tail the articulation appears to indicate a stiff con- 
dition ; but in the lower part of the tail the articular faces are 
fairly concave. Notwithstanding the worn state of the specimens, 
they all agree so perfectly in character, and are so different from 
any other remains that have been found, that no doubt can be 
entertained as to their being portions of a single animal. It is 
impossible to tell how much of the abrasion was produced in the 
washing-mill, and how much before fossilization ; but as the bones 
show evidence of fracture and decomposition, it is probable that 
much of the worn appearance which they present has resulted 
from decay consequent upon maceration and exposure of the up- 
turned surfaces. 
Cervical Vertebra.—Although this specimen is sufficient to give 
important characters of the cervical region, it has neither arti- 
cular end preserved, and shows but little of the neural arch. The 
centrum was about 1,8 inch long and 1,2, inch deep. It is com- 
pressed from side to side, and has the base narrow and rounded. 
The neural arch is defined from the centrum by a deep groove; 
below this groove and behind the upper part of the anterior arti- 
cular face is an indication of the large tubercle for the rib, which 
must have been fully half an inch in diameter. The posterior 
articular face of the centrum was triangular. The platform of 
the neural arch reached to a height above the base of the centrum 
of 2,2, inches. The transverse process for the upper head of the rib 
was directed outward and forward; it is fractured, and is there 
4 inch deep. The neural canal was large, and nearly 1 inch high. 
Dorsal Vertebre.—The next four vertebrae belong to the early 
dorsal region; they differ from the cervical chiefly in being a little 
larger, wanting the tubercle for the rib-articulation, and in 
the increasing depth and width of the centrum. ‘The neural arch 
also, which is partly preserved in three out of the four, is directed 
more obviously outward. But all these vertebre have the same 
compressed centrum, with comparatively flattened sides, converging 
to a narrow rounded base and subtriangular articular terminal ends. 
When the neural arch is broken away, it is seen to have united with 
the centrum by rugose transverse ridges, arranged on a facet which 
