44 RAMSAY H. TRAQUAIR’S 
the superethmoidal prominence which is so marked a feature in the contour of 
the head in typical Paleeoniscidee. 
Holurus Parki, sp. nov. Traquair. 
Pl. III. figs. 9-12. 
Length, 22 inches to apparently over 3 inches; shape fusiform, and rather 
deep ; greatest depth of body contained about 33 times, and the length of the 
head a little over 4 times in the total. 
Of the cranial roof bones, the parietals, squamosals, and frontals may be 
readily identified, and these are ornamented externally with sharp and delicate, 
sometimes passing into elongated tubercles. The suspensorium is oblique ; 
the opercular bones seem rather small, and from defective preservation their 
external ornament is not well shown, though in the operculum a few raised 
striz similar to those of the other cranial plates may be observed. The 
maxilla has its upper margin as usual cut away in front for the orbit, but not 
quite so suddenly as in most Paleoniscide ; its broad post-orbital portion is 
ornamented with delicate ridges running parallel with the superior and posterior 
margins. The mandible is of medium stoutness ; its outer surface shows traces 
of delicate striation. Only very few teeth can, with considerable difficulty, be 
detected ; they are minute and cylindro-conical in shape. 
So far as exhibited, the bones of the shoulder girdle are in every respect 
conformed according to the usual paleeoniscoid type, and are ornamented ex- 
ternally with ridges similar to those of the head bones. 
The body scales are rather small for the size of the fish, rhomboidal, and 
very ornately sculptured with minute and delicate, yet very distinctly marked 
ridges and furrows, whose general pattern on the flank scales (fig. 10) may be 
described as follows :—Below a diagonal running between the anterior, superior, 
and posterior-inferior angles of the scale, their ridges have a nearly horizontal 
direction, parallel with the lower margin, some of the lowest also turning up 
along the anterior margin; immediately above this diagonal some ridges are 
seen running downwards and backwards parallel with it, while the uppermost 
pass backwards parallel with the upper margin, and then turn down parallel 
with the upper part of the posterior one ; a few denticulations of the posterior 
margin are usually seen about the middle. Further back the denticulations 
disappear, the pattern becomes less marked, the ridges tend to fuse together, 
and the intervening furrows to degenerate into streaks and punctures, till at 
last the minute lozenge-shaped scales on the sides of the powerful caudal body- 
prolongation are nearly smooth. Along the middle line of the back, com- 
mencing near the occiput and extending to the dorsal fin, is a row of large and 
conspicuous median imbricating scales (fig. 12), each emarginate in front, pointed 
behind, and becoming more and more acute as the dorsal fin is approached ; 
