CESTRACrONTID.®. 
261 
of the head, and the anterior fragment somewhat misplaced, 
a small intermediate portion in the upper part of the 
fracture being wanting. EnnisJdllen Coll. 
40352. Imperfect remains of the skull and mandible and other 
cartilages, with part of the slightly scattered dentition, 
shagreen, and three of the SphenoiicM,” Purchased, 1867. 
P. 3171. Imperfect left mandibular and pterygo-quadrate cartilages, 
and other fragments, with a few broken teeth. 
Ennislcillen Coll. 
35792. Fragment of cartilage and teeth. Purchased, 1860. 
P. 2781. Remains of cartilage, shagreen, and a few large teeth, in 
very hard matrix, identical in character with that of the 
next specimen. Enniskillen Coll. 
20570. Group of displaced teeth, forming the type specimen of If. 
pi/ramidalis, Agassiz. As remarked above, the teeth 
exhibit much variation in size and form, and four are 
shown, of the natural size, in PI. X. figs. 1-4. Only a few 
have the median eminence relatively so largo as indicated 
in the figure in the ‘ Poiss. Foss.’ Johnson Coll. 
P. 2795. A broken small slab of Lias, showing about seventy teeth, 
some in their natural relative positions. Those originally 
occupying the middle of the side of the jaw measure 
0-023 in their long diameter, while those at the symphysi.s 
only have a corresponding measurement of about 0-01.5. 
In the latter, the coronal cusps are relatively high, and the 
large fibrous base is very broad. Enniskillen Coll. 
P. 2791. Teeth of the four hindermost series in the jaw, arranged 
in their original relative positions, and shown, of the 
natural size, in PI. X. fig. .5. The teeth of the third row 
preserved (6) arc very similar to the imperfect example 
from the type specimen of II. pyramidalis Ugarcdm PI. X. 
fig. 4, and those of the second row also resemble one of 
the last-named fossil. There can thus be little doubt as 
to the specific determination of the present specimen. As 
shown in side view (figs. 5 a-c), the coronal cusps are less 
elevated and more rounded than those of the more an- 
teriorly placed teeth. Enniskillen Coll. 
P. 2799. Portions of four series of teeth, naturally arranged, with 
fragments of cartilage and shagreen. Enniskillen Coll. 
