492 
ACTINOPTEETGII. 
28711. Imperfect anterior portion of cranium, wanting rostrum, 
shown of the natural size from the upper and left lateral 
aspects in PI. XIX. figs. 1, I a ; Shepp^y. The bones 
exhibit a coarsely fibrous texture. The greater portion of 
the left frontal (/r.) is seen, with a fragment of that of 
the right side. In front of these there occurs a median 
element {eth.\ which seems to be a membrane-bone on 
the ethmoidal region rather than the mesethmoid itself. 
Another median pair of bones, evidently long and narrow, 
quite at the base of the rostrum, are doubtless to be 
interpreted as nasals (na.). The position of the orbit is 
marked by remains of the ossified sclerotic {sd.). Shortly 
in advance of this a trace of the prefrontal (ectethmoid) 
projects through the matrix on the left side (pr./.), while 
its fellow is still better exposed on the right. The 
maxilla {mx.) is preserved on both sides, and its upper 
expansion is articulated with the antero-external border 
of the frontal, besides being almost or quite in contact 
with the ethmoidal plate, and distinctly in contact with 
the hinder part of the outer border of the nasal. The 
rod-like backward extension of the maxilla beneath the 
orbit is shown on the right side, though it is broken away 
from the main part of the bone. Remains of the pre¬ 
maxilla, which is much smoother than the other bones, 
are seen on both sides. Part of this element occurs in its 
natural position on the left {pmx.') ; while the fragments 
on the right show that it bore clustered minute teeth 
(fig. 1 h) and completely excluded the maxilla from the 
gape. Purchased, 1853. 
32387. Hinder half of cranium in hard nodule, exposing the cranial 
roof, which is shown of the natural size in PI. XIX. 
fig. 2 ; Sheppey. The two pairs of fossae for the forward 
extension of the lateral muscles of the trunk are very 
small and restricted to the occipital border. The roof is 
gently and regularly convex. The supraoccipital {s.occ.) 
is large and extends forwards to the frontals ; it is a little 
expanded in front, and bears a small median vertical crest 
behind. Its postero-external angle is in contact with the 
epiotic {ep.o.), which is large and prominent but onlj^ 
preserved on the right side. The parietals (pa.) are long 
and narrow bones extending nearly as far forwards as the 
supraoccipital; they are fianked by an equally long and 
narrow pair of squamosals (s^'.). The otic region beneath 
