36 THE ROYAL SOCIETY-OF -CANADA 
interbedded the thin layers of calcareous sandstone in which the 
fish remains are found. The shales exposed at Massive extend a 
few miles northward toward Johnson creek and it is in their northern 
extension that Mr. McLennan obtained his specimens at the second 
locality. 
The very large species of Platysomus which I described in 1914 
in the Transactions of the Royal Society of Canada, is preserved 
in a rock lithologically identical with that of the above two localities 
and differing only in having the brown tinge of the dark grey colour 
less accentuated. E. W. Peyto, of Banff, the discoverer of the type 
of Platysomus canadensis, Lambe, did not reveal the exact place 
where his specimen was found but it is understood to be near Johnson 
creek and is in all likelihood from the set of beds outcropping at Mas- 
sive and on the Johnston Creek trail. In the paper descriptive of 
Platysomus the beds from which the specimen came were referred 
to as presumably of Permian age. 
The genera represented in the 1915 collections are—Celacanthus, 
Elonichthys and Acrolepts. 
The Crossopterygian family Cœlacanthidæ ranges from the 
Devonian to the upper Cretaceous. The type genus Ccelacanthus 
is found on both sides of the Atlantic in the Carboniferous and Per- 
mian and is best known in North America from the Coal Measures 
of Ohio, U.S.A. The Actinopterygian genera Elonichthys and 
Acrolepis, of the family Palæoniscidae, include Carboniferous and 
Permian forms. The discovery, therefore, of species belonging to 
the above three genera in rocks of lower Triassic age extends their 
known upward range, if the generic relations of the specimens collected 
by Mr. Burling and Mr. McLennan are correctly interpreted. If 
in this small but interesting fish fauna we include Platysomus canadensis 
as belonging to this horizon, we also extend the range of Platysomus 
upward from the upper Permian, the highest horizon at which Platy- 
somus has hitherto been known to occur. 
In this paper descriptions with figures are given of the specimens 
collected in 1915. The generic determinations are tentative only. 
In the case of the specimen referred to Elonichthys, although the sum 
of the characters displayed point to that genus as the one to which 
the species probably belongs, the absence of such important parts 
as the head and tail makes an exact determination difficult. The 
great size of the pectoral fin is a very marked feature of this fish 
and in no described species with the suggested generic affinities of 
this one is so large a pectoral fin present. The species is described 
as new. In the case of the specimens referred to Coelacanthus and 
Acrolepis more comprehensive material is most desirable and may 
