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ERIK A : SON STENSIO 
rows some scales whose height exceeds their width (PI. 32 , fig. 2), and ventrally of them 
there then follow some enlarged scales, which gradually, as they approach the ventral 
side, become low. In the most posterior part of the caudal region the scales gradually 
become smaller and almost rhombic. 
The scales generally appear to have been fairly thin. Their anterior covered area 
is relatively wide, at least in the abdominal region. Their dorsal margin has in this 
region a distinct articulatory spine, apart from the lowest scales farthest dorsally and 
ventrally. The medial surface on each scale is furnished with a vertical ridge and has, 
in the usual way, close to the ventral margin, a fossa for articulation with the spine 
on the nearest ventral scale of the same vertical row. It is impossible to establish with 
certainty whether the posterior margin was entire or serrated. 
The sculpture of the scales consists of striation and is obviously stronger and 
coarser on the ventral parts of the fish than on the other. On the scales belonging to 
the ventral side several of the striae are wider than the interwals between them, or at 
least of the same width. Higher up on the scales of the lateral surfaces of the body 
the striae gradually become narrower, while the intervals between them increase in 
proportion. On the scales towards the dorsum, where the striation is finest, the width 
of the striae is only half to a third that of the intervals, or perhaps even less. 
On the majority of the scales the striae can be subdivided into three categories, 
of which those belonging to the most striking one (PI. 3 i, fig. 5; PI. 32 , fig. 2) run 
across a large part of the exposed surface obliquely backwards and downwards to the 
lower and posterior margins, gradually becoming narrower as they approach to these 
margins. On the ventral scales there are only two or three of these striae. On the scales 
of the lateral surfaces of the abdominal region their number gradually increases to the 
same degree as the scales themselves increase in height, finally decreasing again towards 
the dorsum. On the higher anterior scales immediately behind the shoulder girdle they 
number i6 : —20 (PI. 32 , fig. 2); somewhat farther posteriorly, on the middle part of the 
abdominal region, they are 10—12, growing gradually fewer towards the caudal region. 
On the ventral scales the most ventral of them is bent upwards at the anterior end in front 
of the others, so that it becomes nearly parallel to the anterior margin. On the scales 
where the striae of the category in question are more numerous, except on those situated 
immediately behind the shoulder girdle, the two, sometimes even the three or four ventral 
striae (PI. 3 i, fig. 5) are often bend round in a dorsal direction in the same way, but 
not infrequently their upward bent parts are not continous with the other ones but 
subdivided into a row of somewhat lengthened tubercles. Finally it is noteworthy that 
the long striae running across the scales never anastomose and that they show a fine 
corrugation especially on the scales of the ventral side. 
The striae belonging to the next category occur only along the posterior margin 
of the scales between the posterior ends of the previously described ones, and are very 
short and fine; their number is most often rather great. 
Finally the striae belonging to the third category occur farthest anteriorly on the 
exposed surface of the scales in front of all the rest and pass off downwards from 
above, parallel to the anterior margin. They are lacking on the scales in a couple 
of the rows following closest to the shoulder girdle and are also probably not developed 
