40 RAMSAY H. TRAQUAIR’S 
distinctly made out on either jaw. The orbit is large, but is, as usual, 
anteriorly placed, and the ethmoid forms a rounded prominence above the 
mouth. The bones of the shoulder girdle present nothing peculiar in their 
configuration and arrangement. 
Immediately behind the upper limb of the clavicle, a few scales are visible, 
apparently the remnants of two or three dorso-ventral bands ; they are very 
indistinctly preserved, yet their shape appears to be rhomboidal, and somewhat 
higher than long; and, though traces of ganoine appear on their surfaces, no 
sculptured pattern is visible. From this part, as far as the caudal fin, not the 
slightest trace of scales of any kind can be perceived,* except in one specimen, 
where there are four well-preserved median scales in front of the dorsal fin. 
But in all, the caudal body-prolongation is furnished with scales, which are as 
solid and as well preserved as in any other ganoid of similar size from the same 
beds. Along the upper margin of this part we find the usual median row of 
pointed imbricating scales, and simultaneously with these there commences a 
band of lateral ones, clothing the side of the prolonged body axis, these being 
very minute, acutely lozenge-shaped, and marked each with a few fine diagonal 
grooves ; this band of lateral scales does not, however, extend to the origin of 
the caudal fin rays until the base of the lower lobe is passed. A few imbri- 
cating median scales may also be seen just in front of the commencement of the 
lower lobes of the caudal fin. 
The absence of body scales reveals the internal skeleton in a manner 
unusually distinct for fishes of this family. There is no trace of vertebral 
bodies, the position of the persistent notochord being indicated by an empty 
space. Above this there is a series of short neural spines, bifurcated 
proximally, and slightly dilated distally, sixteen of which very regularly 
placed may, in one specimen, be counted between the head and the dorsal 
fin, beyond which they are a little confused; but they are again seen in 
more undisturbed succession towards the tail, where they assume a much 
more backward inclination than in front. Again, above these the dorsal 
fin is supported by two sets of slender interspinous bones, proximal and distal. 
The proximal set are directly superimposed on the extremities of the neural 
spines, but they are more numerous and consequently more closely placed ; 
their exact number is not ascertainable, though I count thirteen of them to seven 
spines. Their distal extremities articulate with the proximal ends of the 
second set, with which they correspond in number; the latter are somewhat 
shorter, and have both extremities somewhat dilated. 
On the hzemal aspect of the notochordal space, there may be seen between 
* In the specimen figured, a tolerably large scale lies irregularly across the middle of the body ; 
but this, being evidently a dorsal ridge scale, is clearly out of its place, and probably belonged to some 
other fish, 
