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ERIK A : SON STENSIO 
caudal lobe gradually become higher and narrower towards the extremity of the lobe. 
No large or prominent ridge-scales have been developed either above the abdominal or 
the caudal region apart from those over the dorsal lobe of the caudal fin. As far as 
can be seen the anterior covered area of the scales is narrow. Their upper margin has 
a distinct articulatory spine and the medial surface, as usual, a vertical ridge. The 
posterior margin is distinctly serrate. 1 ) The exposed part of the lateral surface is quite 
covered with ganoine. 
The sculpture consists of obliquely placed folds or striae, issuing from or in the 
neighbourhood of the anterior and dorsal margins of the exposed surface of each scale 
and running fairly parallel to one another backwards and downwards towards the low T er 
and posterior margins. 
On the scales that have belonged to the anterior and middle parts of the body 
this sculpture is present over all the exposed surface, and the striae there are broad, 
comparatively strong' and sharp. One or two of them, situated farthest ventrally on each 
of these scales, are often also bent in the way that their posterior half is parallel to 
the ventral margin of the scale and the anterior half to the anterior margin. Otherwise 
the striae on the scales in question are often somewhat irregular and the middle ones 
on each scale do not reach continuously across the whole of the exposed surface, 
but two or three shorter striae follow one another or alternate with each othdr there. 
Towards the posterior part of the abdominal region the sculpture is gradually 
weakened on the postero-ventral half of the scales, in the caudal region being restricted 
mainly to the antero-dorsal half (PI. 25, fig. 2). Most of the scales covering the dorsal 
lobe of the caudal fin entirely lack sculpture, only the most anterior ones having traces of 
it. It is also noteworthy that the sculpture on the scales of the posterior parts of the body 
consists only of diagonal striae. In connection with this partial reduction of the sculpture 
the remaining parts of the striae also decrease in strength and become more rounded. 
Remarks. — Glaucolepis gyrolepidoid.es comprises in its present definition material 
from different horizons, and it must therefore be considered possible that the species 
name suggested here may turn out to be a collective name for a couple of species. 
In the sculpture of the scales Glaucolepis gyrolepidoides is confusingly like certain 
Gyrolepis species, e. g. Gyrolepis alberti, and it is this fact that I have indicated by the 
species name gyrolepidoides. 
Geological occurrence and localities. — Detached scales of this species 
are found within the Ice Fjord district in the bone-bed 33 m above the fish horizon, at 
Mt Viking, and in a bone-bed about 50 m above the fish horizon on Corrie Down, and 
in the material from the bone-bed found by Salomon in the lower Triassic of Mt. Congress. 
In addition, as I have show r n, detached scales occur in the Triassic strata at Horn Sound 
(Stensio, 1918 b, loc. cit.). 
Specimens P. 166, P. 6yi a, P. 6yi b and the specimen in the possession of the 
Palaeontological Collection of the University of Christiania previously noticed by me 
J ) In Gyrolepis too I have found serration on the posterior margin of the scales, e. g. in G. alberti and 
G. agassizi (cf. Dames, 1888, Tafel 1, fig. 1 a, b; Tafel III, fig. 1 c, d; Tafel V, fig. 2 a, b). 
