Echinoid Jaw-fragments. 138 
and attains a width of 1°2 mm. in its upper third, but becomes thinner near the lower 
end of the fovea magna externa, which is narrow and deeply indented. The upper 
end of the admedian plane is obliquely cut off by the boundary of the supra- 
alveolar process, which is slightly concave. 
The symphysial face appears to have been narrow, widening below. Its length 
is 90 mm., i. e. 0°93 of the whole length, which, however, is probably not quite 
complete. 
The internal face is too much worn for description, but the lineae eminentes 
can never have been very prominent. 
Vessprém-Futas Ry., Cutting I. (b) 
(Plate IX, figs. 282—234.) 
A right alveolus from bed e. Raiblian. 
Interpyramidal joint-face narrow, (fig. 232) but margins are broken. Slope of aboral 
margin uncertain. Transverse ridges at right angles to the long axis of the joint-face, 
and almost straight, with a very faint S curve, bending downwards externally and 
upwards internally; 6 go to 1°0 mm. 
Outer surface (fig. 253) narrow, with fairly well marked convexity. Too imper- 
fect for accurate measurement. External margin thick. Admedian outer plane smooth, 
narrower below. Fovea magna deeply excavate. 
Symphysial face 0°35 mm. wide, tapering slightly below. 
Internal face (fig. 284): narrow central canal. Well marked lineae eminentes. 
Dental slide concave, the concavity being mainly in its outer half. Styloid process 
apparently continued as a ridge up the supra-alveolar process. 
On the whole this specimen appears to belong to the same species as Jeru- 
zsalemhegy b. 
Vessprém-Futas Ry., Cutting I. (c, d, e). 
(Plate IX, figs. 235—237) 
Three maxillae, all of the same form. Raiblian. 
(c) A large right one (figs. 235—237). 
(d) A medium sized left one. 
(e) A small right one, obscured by tenacious matrix. 
The following description is based upon c and d, the measurements being 
from c. 
Interpyramidal joint-face (fig. 235) moderately wide. Length 10 mm.; actual width 
4°3 mm., but since the oesophageal border is broken, it was probably a little more, 
perhaps about 5°0 mm. The face is irregularly curved, rising towards the adoral 
end of the maxilla, which projects beyond the joint-face. The adoral margin slopes 
inwards and downwards. The transverse ridges slope more strongly in the same 
direction and have also a curve with downward convexity ; they are very faint, 
especially in the aboral third of the joint-face. About 5!/, go to 1 mm. The fossa 
arcualis is moderately wide, 2°5 mm. at the base of the supra-alveolar process, 
which is 3°9 mm. high. 
