860 
SliLACHII. 
Oonus ODONTASPIS, Agassiz. 
[Poiss. Foss. vol. iii. 183S, p. 87.] 
Syn. Triylochis, Miillor & Ilenle, Mag. Nat. Hist. ii. s. vol. ii. 1838, 
p. 88. 
(^)Oxytes, C. G. Gietel, Fauna dor Vorwolt, Fische, 1847, p. 364. 
Second dorsal fin and the anal of equal size, scarcely smaller than 
the first dorsal. No pit at the root of the caudal ; side of the tail 
without keel. Teeth of all but the few hindermost series with a 
high, narrow, eompressed coronal eminence, flanked bj' one or two 
pairs of small pointed denticles ; the fourth tooth from the symphysis 
upon each side of the uppc'r jaw very small : the teeth of the most 
anterior pair in the lower jaw small and relatively very slender. 
As remarked by Agassiz, it is very difficult to distinguish the 
teeth of this genus from those of Lamna, the only difference appa- 
rently being the greater relative size and more subulate character of 
the anterior teeth in Odontasjiis. From Scapanorhynchus the teeth 
differ in no essential respects. 
Odontaspis bronni, Agassiz. 
1843. Lmmui (OiJonianpls) hrnnni, L. .\gassiz, Poiss. Foss. vol. iii. p. 297, 
pi. xxxvii. «. figs. 8-10. 
(.'') 1843. Otodux serratns, L. Agassiz, tom. cit. p. 272, pi. xxxii. figs. 
27, 28. 
1862. Otodiis and Lamna, P. Gervais, Zool. et Pal. Fran^. pi. Ixxvi. 
tigs. 6, 8 
Type. Detached tooth. 
Teeth robust, the crown of the anterior teetti attaining a height 
of about 0-018, with but the slightest sigmoidal curvature. Outer 
coronal face convex, more or less uneven, and sometimes vertically 
folded towards the basal line, which is transversely straight ; inner 
face smooth ; two pairs of pointed lateral denticles generally present, 
the outer insignificant. Pase of crown in lateral teeth overhanging 
the root in front. Nutritive foramen of the root in a deep groove. 
The upper postero-lateral teeth are probably those named Otodu.x 
sermtds, Agassiz. 
Ihe teeth of 0. acuta, J. W. Davis, from the Oamaru System of 
New Zealand, are very similar to those of this species. 
Form, tj- Loc. Danian : Holland and Belgium. 
42984. Six teeth ; Maastricht. Van Breda Coll. 
■ To (his species may also probably be assigned the Maastricht tooth named 
Odmituspix hopci by F. Bassani. Atti Soc. Venelo-Trent. Sci. Nat. vol. vii. (1880), 
p. 10, pi. c. fig. 1. 
