362 RAMSAY H. TRAQUAIR ON THE 
is somewhat displaced, but from the position of the operculum and the 
direction of the bones of the shoulder girdle, it is clear that the axis of this 
element must have been, as in other Platysomids, downwards and slightly 
forwards. The operculum (op) is somewhat square-shaped, its posterior- 
superior angle being rounded, and its straight anterior margin nearly vertical 
with a slight forward inclination ; below it is a larger plate (7. op), which is 
evidently the cnteroperculum a little dislocated from its position ; no branchi- 
ostegal rays are preserved. The mazilla (mx) is shaped much as in Mesolepis, 
but the angle between its inferior and posterior margins is very much rounded 
off, so as to be nearly obsolete; as in that genus, a small laminar projection 
passes off from its superior margin close behind its bluntly pointed anterior 
extremity ; no teeth are shown. The mandible is not exhibited at all in the 
specimen. The post-temporal element of the shoulder girdle (p.7¢) most nearly 
resembles that of Platysomus, and is a large, somewhat square-shaped plate, 
with its posterior angles somewhat rounded off, placed right behind the 
parietal, and apparently in contact above with its fellow of the opposite side. 
The supra-clavicular (s.cl) is of considerable size, vertically oblong, rather 
broad above, where it is obliquely traversed by the lateral slime canal, and 
narrowing to a point below, where it is in contact with an elongated clavicle (cl) 
of the usual Platysomid form. Of the fins, only the dorsal and anal are 
preserved, and the latter is not in good condition. The dorsal is small, arising 
considerably behind the middle of the arch of the back, and both in that 
circumstance and in its shape it resembles the dorsal of Benedenius. It is 
acuminate in front, becoming fringe-like behind, and terminates at the com- 
mencement of the narrow tail pedicle; its anterior margin is distinctly ful- 
crated. But from what is seen of the anal, it is evident that it possessed a 
more extended base than that of Benedenius, and was conformed much like 
the dorsal. Unfortunately the caudal is not present in specimen, but the 
analogy of the rest of the structure of the fish leaves no reason for doubt as — 
to its having been heterocercal. The scales of the side of the body (figs. 13 
and 14) are high and narrow, and shaped according to the same general type 
seen in Mesolepis or Platysomus. The articular spine and internal rib are mode- 
rately developed; externally the smooth overlapped marginal area is well 
defined, while the free surface is ornamented with raised tubercles, which tend 
to be arranged in lines or to coalesce into short ridges, whose direction is 
across the scale from before backwards, some downward radiation towards the 
posterior-inferior angle being often observed at the lower part. As usual, the 
scales become more equilateral towards the dorsal and ventral margins (fig. 15), 
and the middle dorsal and ventral lines in front of the dorsal and anal fins 
are evidently furnished respectively with rows of azygous scales, having back- 
wardly directed spur-shaped points. 
