TRIASSIC FISHES FROM SPITZBERGEN 
i3 
secondary longitudinal crista is formed, which passes along the primary one and nearly 
parallel to it. We thus find here the character developed that is specially characteristic 
of Hulke’s type-tooth. On the other half of the lateral surface of the tooth this tendency 
to curvature of the striae is evident only close to the principal cone. In other respects 
the striae on this half have a rather vertical position and fairly often reach, especially 
towards the end of the crown, the primary crista, so that under these circumstances 
the smooth longitudinal zone does not exist at this place. 
The root has its basal surface placed horizontally in relation to the axis of height 
of the principal cone. 
The tooth P. 98 b, which is represented only by a small part (PI. 2, fig. 7), has had 
a rather large number of lateral cones, all of which, however, seem to be very small. 
A tendency towards the development of a secondary longitudinal crista can be observed 
laterally of the primary one. Between both there is a sculptureless longitudinal groove. 
The root is low and the basal surface is developed in correspondence with that of the 
tooth just described. 
Teeth belonging to the middle and posterior transverse rows. — Under 
this heading I have grouped together the teeth P. 98 c — m, P. 100 and in addition some 
of those found at Horn Sound. 
The tooth P. 98 c (PI. 2, fig. 8) has been comparatively large. Its length especially 
seems to have been considerable. What is now preserved, however, is only an end 
part, and consequently it is impossible to obtain any exact idea of the appearance and 
proportions of the tooth as a whole. Both the root and the crown are curved as in 
the tooth P. 98 a, but the curvature is much less. The crown has a primary longitudinal 
crista clearly developed, and in addition there is a rather long secondary longitudinal 
one present laterally of the former. Between the two the surface of the crown is 
slightly sunk and forms, as in the tooth described by Hulke, a real longitudinal groove. 
The rest of the sculpture consists of transverse striation. On the medial surface the 
striae are restricted to the neighbourhood of the basal margin of the crown except 
for a few that issue from the primary longitudinal crista. They are all very short. On 
the lateral surface the striae are coarser and longer, but are discontinous at the middle 
part, so that proximal stumps of them are situated close to the basal edge of the crown, 
while the distal ones are attached to one another and form the secondary longitudinal 
crista (cf. PI. 2, fig. 8 a). — The appearance of the crown and the root in cross section 
is seen in text fig. 4 B. The basal surface of the root is placed obliquely so that it 
faces ventro-laterally. 
The tooth P. 98 d (PI. 2, fig. 9) is very incompletely preserved, but, as far as can 
be seen, it has resembled P. 98 c. It differs from this only by having some of the 
transverse striae attached to the primary longitudinal crista both on the lateral and 
medial side and in not having any secondary longitudinal crista developed — at least 
not on the small part present. 
Of the tooth P. 98e (PI. 2, fig. 10) a part is preserved that originally had a position 
somewhat to the side of the middle. It is impossible to establish whether this part 
belonged to the anterior or posterior half of the tooth. As far as can be judged, this 
tooth was probably about as large as P. 98 c. Both the root and the crown seem 
