a new Chelonian. 149 
The ento- and epiplastra are relatively small. The former 
Is semicircular in outline posteriorly, while in front it is 
bounded by two nearly straight borders meeting at a very 
obtuse angle and abutting against the epiplastra, which meet 
on the middle line in front of it. The suture between the 
hyo- and hypoplastra crosses the middle of the bridge; there 
is no trace of a mesoplastron. ‘The suture between the hypo- 
and xiphiplastra starts from about the middle of the posterior 
lobe ; it first runs directly outwards, then turns sharply 
forwards for a short distance, and then backwards again to 
the margin. The anterior lobe is broadly rounded in front, 
its sides being nearly parallel; the posterior lobe narrows 
gradually backwards, and probably terminated in a blunt 
point as in the Hmys jaccardi of Pictet. 
There were gular and intergular epidermal shields, but 
whether the latter was single or paired cannot be made out. 
‘he form and relations of the shields*are shown in fig. 2; 
it may be noted that the anal shields are entirely confined to 
the xiphiplastral bone and that externally the pectoral and 
abdominal shields are bordered by a series of inframarginal 
shields, at least four in number. 
On the upper surface of the xiphiplastron, towards its outer 
and posterior edge, there is an obscure oval, slightly depressed, 
and roughened scar, more distinctly shown on the right than 
on the left side; this no doubt marks the point of contact with 
the lower end of the pubis, with which, however, no fusion 
took place. 
‘he plastron, as a whole, is much more massively con- 
structed than one would expect from the carapace; thus, on 
the middle line the hypoplastron is about 20 mm. in thickuess, 
forming a distinct prominence on the inner surface. 
The whole surface of the carapace is covered with irregu- 
larly rounded pits of varying size. These do not appear to 
represent a real sculpture, but to result from the action of 
local decomposition. Riitimeyer* has described similar pits 
in some shells of Plesiochelys, and suggested that they were 
formed by the decomposition of nodules of pyrites. It this is 
the explanation, it is, however, curious that these pits, while 
very numerous on the outer surface of the carapace, do not 
occur on the inner side. On the plastron only a few pits of 
rather larger size are developed. 
A certain number of limb-bones, vertebrae, and fragments 
of skull were found associated with the shell. The skull- 
fragments are too imperfect for description. Of the fore limb 
* “ Die fossilen Schildkréten von Solothurn,” Neue Denksch. Schweiz. 
Gesellsch. Naturwiss, vol. xxv. (1878) p. 84. 
