437 
of Edinburgh^ Session 1876 - 77 . 
Rhadinichtliys lepturus, sp. nov. Traquair. 
I* am indebted to Dr Paterson, of Leith, and to Mr R. Etheridge, 
jun., for the loan of two specimens of a small Rhadinichtliys from 
Grange Quarry, Burntisland, which appears to belong to a new 
species. With these I can identify a detached tail recently found 
by myself in the same locality. 
Description . — The length of Dr Paterson’s specimen is 3 \ inches, 
allowing for the extremity of the snout, which is deficient. The 
depth of the body, midway between the head and the dorsal fin, is 
inch ; that of the tail pedicle at the commencement of the lower 
lobe of the caudal is ~ inch. It is, however, just possible that the 
anterior part of the fish may be a little shortened up by one of the 
common forms of distortion, as, on the other hand, the whole shape 
of the other specimen belonging to Mr Etheridge certainly is unnatur- 
ally attenuated by a similar cause. Nevertheless, we have before us 
a small fish of a fusiform shape, elegantly tapering posteriorly to a very 
narrow tail pedicle, the dorsal and anal fins being nearly opposite each 
other, and a well-marked interval occurring between the latter and the 
commencement of the caudal, which is rather small and of a delicate 
appearance. Nothing can be said regarding the head, which is 
hopelessly crushed. The scales are of medium size, becoming 
rapidly smaller posteriorly. Those of the anterior part .of the body 
have their outer surfaces entirely covered by a delicate sculpture 
consisting of fine furrows and ridges passing across the scale, and 
ending in the denticulations of the posterior margin, those of the 
upper and posterior part of the area being more oblique than those 
of the lower and anterior. On the posterior part of the fish the 
scales are seen only from their inner or attached surfaces. The 
origin of the pectoral fin is seen in the second specimen referred to, 
but it is in very bad preservation. Returning to Dr Paterson’s 
specimen, a few rays of the ventral are seen, but the real size and 
shape of the fin are not shown. The dorsal and anal fins are 
moderate, and of the same form, triangular, concavely cut out 
behind, with delicate rays, whose transverse joints are considerably 
longer than they are broad. The dorsal commences only very 
slightly in front of the origin of the anal, and an interval, equal to 
■§ the length of the base of the anal, occurs between its posterior 
termination and the commencement of tne lower lobe of the caudal. 
3 M 
VOL. IX. 
