200 
ERIK A:SON STENSIO 
vertical striae, and in many cases this striation extends quite to the point of the cap. 
The enamel-covered part basally of the enamel cap has a very fine striation, as on the 
typical teeth from the fish horizon. 
Remarks. — The teeth described here in general show the closest resemblance 
in shape to the teeth of the gill-arches in B. mougeoti, but differ from these by having 
striation on the enamel cap. Since this striation, as has been mentioned, often extends 
right out to the point, it gives the teeth a character that clearly differentiates them from 
teeth belonging to B. mougeoti. For this reason I consider it probable that they may 
belong to a new species. 
Geological occurrence and locality. — The teeth in question are only 
known from the upper Triassic, where they are found at Mt. Bertil in a bone-bed about 
263 m above the fish horizon. 
Genus Glaucolepis n. g. 
Synonym: Gyrolepis ? Stensio, 1918. 
The species referred to in my notice of the Triassic fish remains from Horn Sound 
as Gyrolepis? sp. (Stensio, 1918b, p. 77) has with the present material turned out to be¬ 
long to a previously unknown genus, for which I suggest the name Glaucolepis. 
The most characteristic features so far known of this new genus can be summa¬ 
rized as follows: Small fishes with rather slender bodies. Pectoral fins unknown. Other 
fins weak with closely jointed and bifurcated lepidotrichia. The anal and dorsal fins 
with a short base and small fulcra. The dorsal fin has its posterior half opposite the 
anterior half of the anal fin. The caudal fin is deeply cleft with both lobes somewhat 
similarly developed, or possibly the ventral one somewhat stronger than the dorsal one; 
the dorsal one has rather large ridge-scales, the ventral one small fulcra. The scales on 
the anterior part of the lateral surfaces of the body are somewhat longer than wide; 
farther back they are rhombic, and towards the ventral side, especially in the abdominal 
regiofi and the anterior part of the caudal region, they are low. Dorsal ridge-scales 
presumably small and not prominent. All scales have the anterior covered area narrow; 
the exposed one is totally covered by a layer of shining ganoine. This ganoine layer 
has raised ridges, mostly running more or less diagonally. 
With regard to the sculpture of certain of the scales Glaucolepis is confusingly 
like Gyrolepis. The similarity is even so great that it would be very difficult or impossible to 
distinguish the two genera from each other only with the help of detached scales. An¬ 
other resemblance between them is found in the absence of enlarged ridge-scales in the 
abdominal region and the anterior part of the caudal region. Glaucolepis is distinguished 
clearly, however, from Gyrolepis by the shape of the unpaired fins and their weak 
development (cf. Dames, 1888, pp. 5—23, Tafel I, Tafel III, fig. ia, b; Stolley, 1920, 
pp. 25—28, Tafel X, fig. 1). 
The small height of the scales on the ventral side is a peculiarity that Glaucolepis shares 
with, inter alia, Platysiagum (Woodward, 1895 b, 533 — 534), Oxygnathus (Woodward, 1891b, 
pp. 516—520), Urolepis (Alessandri, 1910, p.48), Acrolepis (Woodward, 1891 b, pp.501—509). 
