G0N0EHYXCHID2E. 
273 
P. 9173. Type specimen, shown of the natural size iu PI. XV. fig. 3. 
The crushed remains of the head are exposed partly from 
the right side, partly from below. The cranium seems to 
he exposed from beneath, and displays the attenuated 
form of the elongated rostrum. Beneath its anterior 
extremity there lies a stout cuxwed bone {mx.) shaped 
much like the maxilla of Gonorhynclius ; while just behind 
this there appears to be the anterior pointed end of the 
toothless dentary (cZ.). Still further back there are 
remains of large bluntly-conical teeth, some apparently 
belonging to the upper jaw, but the largest (Z.) occurring 
just above the ceratohyal as if they had been fixed upon 
the hyoid arch. All the vertebral centra are longer than 
deep and much constricted; while fractured examples, 
both in the abdominal and caudal regions, seem to indicate 
that a delicate strand of the notochord penetrated each of 
them. The ribs are shown to be short and slender, not 
reaching the ventral border of the fish ; the neural and 
haemal spines in the caudal region are straight, much 
inclined backwards, and comparatively stout, while there 
seems to have been scarcely any fusion or expansion of 
the haemals supporting the caudal fin. The fins are 
closely adpressed to the trunk, so that at first sight they 
are not conspicuous. The remarkably elongated rays of 
the paired fins, however, are well preserved; and the 
arrangement of the fins is clearly as stated in the specific 
diagnosis. The caudal fin is shown to be cleft. The 
scales are antero-posteriorly elongated and striated, but 
their crushed remains are too much confused to permit 
the determination of their precise shape and characters. 
Stout styliform fulcral ridge-scales occur on each border 
of the caudal pedicle at the origin of the caudal fin. 
Lewis Coll. 
49543. More distorted specimen showing small mouth and 
characteristic dentition. Lewis Coll. 
46517. More imperfect specimen, wanting the anterior half of the 
head. Traces of the stout bluntly-conical teeth are 
preserved above and below. Some of the anterior neural 
spines of the abdominal region bear a laminar expansion, 
A few of the'caudal vertebral centra are sufficiently well 
preserved to exhibit their lateral lougitudinal ridge. The 
PAET IV. 
T 
