64 RAMSAY H. TRAQUAIR’S 
and apparently bifurcated so as to form neural arches. Surmounting these, 
there are also very clear indications of a set of slender interspinous bones, 
whose number is at least double that of the supporting neural spines, and 
whose pointed proximal extremities pass a little way down between the ends 
of the latter ; while again, extending from where the fish is cut off behind for 
fully 14 inch towards the head, there are evident remains of a long fringe-like 
dorsal fin—in my opinion, a continuous dorso-caudal. Most probably it would 
be found to extend still further forwards could the matrix be removed. 
On the hemal aspect of the axis, clear evidences of hemal arches and 
spines symmetrical with the neural ones above may be seen about two inches 
behind the head, and may be traced for half an inch backwards, beyond which 
the spines become hopelessly obscured, and nothing remains distinguishable 
but the arches from which they spring. 
Finally, in the layer of matrix which obscures the hinder end of the 
specimen, and close to where it is cut off by the edge of the stone, are many 
minute rhombic glittering scales ; at one spot, three of them, apparently portions 
of a dorso-ventral band, are seen in opposition. ach of these little scales has 
a central depression or sulcus, and is, in fact, indistinguishable from those which 
cover the body in the specimen from Tarras Foot. 
Remarks.—The first question which arises concerning the two specimens 
described above, is whether or not they belong to the same species, and here 
difficulties are certainly interposed by the imperfect condition of both. It will 
be observed, however, that there is a very exact correspondence between the 
two as regards the structure of the internal skeleton, so far as this is exhibited, 
and in the long median fin, which extends along a margin which, in the 
Glencartholm specimen, is certainly the dorsal one. The few scales which 
are seen near the caudal extremity of the specimen last referred to, are 
certainly identical in form and appearance with those which thickly cover the 
surface in that from Tarras Foot, and this circumstance, along with the corre- 
spondence of the internal skeleton and median fin, has inclined me to consider 
the two as belonging to the same species. But it must also be observed that, 
whereas the scales in No. 1 cover the entire surface of what remains of the 
body, in No. 2 not a vestige of them is seen till near the posterior extremity. 
If the two specimens really represent the same species, we are reduced to sup- 
posing that in No. 2 the scales have either been loosened by decay and removed 
from the anterior parts (a state of matters which, though not impossible, seems 
hard to reconcile with the fact that the bones of the head and the vertebral 
apophyses are undisturbed so far as the film of matrix allows them to be seen) ; 
or that the obnoxious film of matrix hides them from view; or lastly, that 
scales were originally present only towards the caudal extremity. It must in 
any case be acknowledged that, until more material turns up, the layer of 
