REPORT ON FOSSIL FISHES. 39 
The pectoral fin is 14 inch in length, and has its principal rays unarticulated 
for the greater part of their length. The origin of the ventral is situated 1°, 
inch behind that of the pectoral; the fin itself is not in good preservation, its 
rays being much broken up, so that its shape and size are lost. The dorsal fin 
is situated nearly opposite the anal, arising opposite a point 4 inches back from 
the tip of the snout; this arises only a little behind the dorsal, and extends 
correspondingly farther back. Both of these fins are rather large, each 
measuring about an inch in length at the base and the same in height 
anteriorly, and the latter measurement would probably be somewhat greater 
were their larger rays preserved up to their extremities, which does not seem 
to be the case. They are also very similar in shape, being triangular and 
acuminate ; their numerous and rather delicate rays have their transverse 
articulations somewhat distant, so that the joints are rather longer than broad ; 
no sculpture is visible. The caudal is incompletely preserved, the extremities 
of both lobes being wanting, but enough is seen to show that it was powerfully 
developed, deeply cleft, and having a body-prolongation of great strength along 
the upper lobe; the rays are similar in character to those of the dorsal and 
anal. Well developed fulcra are seen in connection with the margins of the 
fins wherever these margins are preserved. 
Remarks.—I have considered this strikingly new and beautiful Palzeoniscid 
to be a Rhadinichthys on account of the structure of the pectoral, and the 
relative positions of the dorsal and anal fins, although the caudal body- 
prolongation is more powerfully developed than in the more typical members of 
the genus, such as Rhadinichthys ornatissimus, Rhadinichthys carinatus, &c., and 
although the epithet “slender fish” can hardly be applied to its proportions. 
Its large head, short, thick, fusiform body, peculiar ridged-tuberculate scale 
ornament, and non-denticulated scales, with other peculiarities which need not 
be recapitulated, form an assemblage of specific characters which collectively 
are so novel that no detailed comparison with any other species is necessary. 
Position and Locality—Near Glencartholm, Eskdale, in the Cement-stone 
group of the Calciferous Sandstone series. 
Rhadinichthys (2) angustulus, sp. nov. Traquair. 
Pl. If, figs.,10, 11. 
Two specimens only of this interesting and somewhat doubtful form have 
occurred, one of which, the larger and less perfect, measures 21 inches in 
length, while the other more perfect example attains a length of only 13 inch. 
The length of the head is equal to about + of the total; the greatest depth of 
the body is at the shoulder, and is contained about six times in the entire 
length of the fish, while it is not so much as twice the depth of the tail pedicle, 
the dorsal and ventral margins being nearly straight. The general contour is 
