Devonian Fishes of Canypbelltown and Scaumenac Bay. 119 
like a short break or separation between the anterior and 
posterior portions of the dorsal (or between the two dorsals 
if there were two, which is scarcely probable), but this break 
may be owing to an accidental and abnormal fracture of the 
fin-rays at this point, for in other specimens the two portions 
appear to be continuous.” This break is, however, represented 
in all his figures, including the restored sketch given in his 
second paper in the Zransactions of the Royal Society of 
Canada. 
But on looking carefully through the whole of the 
extensive series of this species collected by Mr Jex last 
summer, and also on re-examining the specimens already 
in the Museum, I find that there is no doubt whatever, that 
in all of them the dorsal fin is in two distinct portions, 
which are separated from each other by a very perceptible 
interval. 
The anterior dorsal commences far forwards ; it is low and 
fringing in character, and the length of its base is contained 
two and a half times in that of the posterior dorsal, the 
interval between the two fins being equal to one-third of 
the length of the base of the anterior. The base of the 
second dorsal extends to a point a little beyond the 
commencement of the lower lobe of the caudal, but as 
its rays are long, and the posterior ones directed nearly 
horizontally backwards, the fin seems to extend near to the 
tip of the tail. It does not, however, form a continuous 
dorso-caudal as in Phaneroplewron, as hitherto described, or 
in Ceratodus or Uronemus, and Mr Whiteaves is certainly in 
error in making it do so in his restored figure already 
referred to. As regards the caudal fin, it is in reality 
heterocercal, the upper lobe being represented only by very 
short rays towards the tip of the body prolongation, while on 
the ventral aspect the lower lobe is of the triangular form 
characteristic of Dipterus. Indeed, the resemblance of the 
fins to those of D. macropterus, Traq., from John o’ Groats, 
is very remarkable, the most striking difference being the 
more extended base and fringing form of the anterior dorsal 
in the species under consideration.  Dipterus Valencrennesia, 
D. macropterus, and Scaumenacia cwrta form then a complete 
