ERIK A : SON STENSIO 
ascertained in the case of one tooth (P. 3 p a), - which, including the principal cone, is 
9 mm high. All the other teeth have their principal cone more' or less defective. 
The best preserved tooth is the one figured in PL i, figs. 3 a and 3 b (Pi 3 pa). 
The crown on this is low with an almost straight basal margin. The principal cone is 
considerably high and is sharply pointed at the distal end. It is not situated vertically 
but is inclined both posteriorly and medially. The lateral cones are low but distinct. 
There are three of them in front of the principal cone. Behind it the tooth is somewhat 
injured and only one of the lateral cones is preserved there. The lateral cones are all 
of a bluntly conical shape. 
The principal cone is somewhat flattened in the latero-medial direction and a 
horizontal section of it is consequently elliptical in shape. Its anterior and posterior 
edges are furnished throughout their length with a sharp cutting keel, which continues 
as a longitudinal keel forwards and backwards to the ends of the crown. 
The sculpture of the crown consists, as usual, of striation. The striae run from 
the basal margin nearly straight upwards as in H. plicatilis. They reach both in front 
of and behind the principal cone to the longitudinal keel. The principal cone itself is 
only striated throughout its height on the medial surface. On the lateral surface it is 
smooth in its distal third. It is also noteworthy with regard to the principal cone that 
the striae are more numerous and more close on its lateral than on its medial surface. 
The root is fairly low, but is strongly developed. Seen from the medial or the 
lateral side it is straight, like the crown. It is considerably wide and forms on the 
medial side a projecting longitudinal torus («Wulst») in the usual way (cf. Jaekel, 1889). 
The basal surface is large and broad and practically quite plane. The axis of height 
of the principal cone meets it at an angle of about 45 0 . 
A tooth agreeing in most respects with the one just described is figured in PI. 1, 
figs. 4 a, b (P. 3 p b). The two ends are here preserved but the principal cone is missing 
to a great extent. It is clear, however, that it has been situated on the middle of the 
tooth. Both in front of and behind it there are remains of two lateral cones. There are 
two more teeth of the same type (P. 3 p c, d; PI. 1, figs. 5, 6); one of these, however* 
(fig. 5) has had the principal cone situated more vertically than the other. All three 
resemble the types that Jaekel, 1889, called H. plicatilis (1889, PI. VII, fig. 3 ) and 
H. longiconus var. minor (1889, PI. VII, fig. 7). 
The tooth figured in PL 1, figs. 7 a, b (P. 3 p e) represents in various respects 
another type than the preceding ones. Both the root and the crown of it are bent 
in the way that they both have concave basal and correspondingly convex distal out¬ 
lines. The principal cone is broken off but it has apparently had an almost vertical 
position. It seems to have a narrower shape than that of the other teeth. The lateral 
cones are low and not very prominent, but at least on one side of the principal cone 
no less than four can by observed. It is also probable that one or more was present 
on the other side, but the tooth is incomplete there and no remains of these are now 
preserved. With regard to sculpture and other details the crown agrees entirely with 
those of the previously described teeth. The root is relatively higher and narrower 
than in these. — As far as can be judged from the present state of preservation this 
tooth resembles most closely the form called H. longiconus by Jaekel 1889. 
