438 
Proceedings of the Royal Society 
The last-named fin is unusually delicate in appearance, the upper 
lobe only very slightly exceeding the lower in length, with a slender 
body prolongation. In the lower lobe the transverse joints of the 
principal rays are longer than they are broad, except just towards 
their terminations. 
Remarks. — In the contour at least of the hinder part of the body 
this species strongly resembles R. carinatus, save that the caudal fin 
is more delicate — the greater apparent depth of the body in front of 
the dorsal fin may be, as already indicated, perhaps accounted for 
by post mortem distortion. The sculpture of the scales, which is 
very different from what we find in R. carinatus , reminds us of R. 
ornatissimus, from which, however, the present species is obviously 
distinguished by the greater delicacy of the rays of the lower lobe of 
the caudal, with their more distant transverse articulations, as well 
as the entire aspect of the fin. It is, however, very possible that 
the imperfect specimen from Burntisland referred by Agassiz to 
il Palceoniscus ” ornatissimus (Poisson’s “Fossiles Atlas,” vol.ii.pl. 10a, 
fig. 7), and in which the tail is deficient, may belong to R. lepturus , 
but his figure being by no means good, it is impossible to decide, in 
the absence of the original specimen. 
Geological Position and Locality. — In calcareous shale overlying 
the “ Burdiehouse ” limestone exposed in Grange Quarry, Burntis- 
land (Calciferous Sandstone series). 
Rhadinichthys Geikiei , sp. nov. Traquair. 
Through the kindness of Professors Bamsay and Geikie I have 
enjoyed the opportunity of examining a number of small specimens 
of Palseoniscidse collected by the Geological Survey from the horizon 
of the Wardie shales near Redhall, among which there is at least 
one beautiful little species of Rhadinichthys hitherto* undescribed. 
This I have much pleasure in dedicating to Professor Geikie, to 
whom I am much indebted for cordial assistance in prosecuting 
the study of Scottish Palaeozoic ichthyology. 
Description. — The specimens are rather fragmentary, except two 
in which the entire fish is shown. Of these the larger has undergone 
an unfortunate twist, but its length may be estimated at 3J inches ; 
the other, measuring only 2J- inches, seems to me to be a younger 
example of the same species. The body is fusiform, the head 
