TRIASSIC FISHES FROM SPITZBERGEN 
3 7 
Row c consists of seven teeth, of the same order of magnitude as in row b 1 but 
somewhat narrower than these in relation to the length. Their length is generally on 
an average about 15 mm, while the greatest width is only 3 mm. The greatest height 
is 4—4’5 mm. 
The majority of the teeth in this row have their anterior end situated lower than 
the posterior one in relation to the labial margin of the mandibula. Otherwise the 
arrangement is the same as in the two rows in front of them. All seven teeth are 
bent in the usual way, so that the masticatory surface is convex from one end to the 
other, while the basal surface of the root is correspondingly concave. Contrary to 
what is the case with teeth belonging to row b the curvature here is strongest in the 
anterior half. The highest and broadest part of the crown is consequently also in 
this half (PI. 3 , fig. i 3 ). 
Anteriorly the crown has a broad, truncated end (PL 3 , figs. i 3 , 16 a, b) which 
meets with the posterior end of the teeth in the preceding row. From this end the 
width of the crown is maintained fairly unaltered posteriorly to its highest part and 
then gradually grows narrower right to the caudal end, which is rather pointed. The 
crown appears, when seen from the masticatory surface, to be also weakly bent in the 
shape of an S, so that its anterior half is convex on the lateral side and its posterior 
half on the medial side. In other respects it shows the same conditions as in the row 
in front, which is also true of the sculpture. 
The root is also developed in a way that resembles very closely what we found 
in row b. 
The five teeth in row d are considerably smaller than in rows b and c. The length 
varies between 5—6 mm, the greatest width is about 2 mm and the greatest height is 
2—2 - 5 mm. Their position is the same as in row c and the curvature and the highest 
part of the crown also show the same conditions as in this row, i. e. they are situated 
nearer the anterior than the posterior end. The widest part coincides with the highest 
part of the crown and the crown grows narrower both to the anterior and the posterior 
ends (text fig. 14), but mostly to the latter end. Otherwise the shape and sculpture 
of the crown closely agree with what we know of the teeth in rows b and c.' The 
root was also developed in them in a similar way. 
The most posterior row, e, consists in its present state of three or four teeth, 
measuring in length about 3 —4 mm and between i‘s—2 mm in height. From the medial 
or the lateral side both the crown and the root are fairly straight or at any rate only 
weakly bent. The conditions of these teeth in other respects cannot be established. 
Among the number of detached teeth that occur on specimen P. 10 7 there are 
some that, apparently, must have been situated still farther forward in the mandible 
than row a or more probably may have belonged to an unpaired symphyseal row. 
These teeth (text figs. 15 B, C; PL 3 , fig. 12) are 4—5 mm in length and their greatest 
height is somewhat more than 3 mm. The crown is strongly bent in the way that it 
is convex from one end to the other, while the base of the root, on the other hand, is 
straight. The two ends of the crown are sometimes bent distally too in the manner 
shown in text figures 15 A, B and PL 3 , fig. 12. A further characteristic of the crown is 
that on one side it has some round protuberances. The sculpture consists of fairly 
