158 FISH-EEMAINS FROM "ROLLING DOAVNS FORMATION" OF N.Q., 



Genus Otodds, Agassiz, 1843. 

 (Rech. Poiss. Foss. Tom. III. p. 266.) 



Otodus appendiculatus, Agassiz. 



0. ajjpendiculatus, Agass., Rech. Poiss. Foss., torn. III. p. 270, 

 Atlas, torn. III. t. 32, f. 1-25. 



Sp. CJiar. — A tooth of the upper jaw, nearly one inch in height 

 from a line di'awn between the fangs upwards to the apex, three- 

 quarters of an inch across the root, and rather less between the 

 fangs. The upper margin of the root describes almost an 

 ellipse, the fangs being thick and obtusely rounded. The crown 

 is rather more than half an inch high, rather flattened on the 

 inner surface, and gently arcuate from before backwards, with the 

 lateral or cutting edges and the apex sharp. The basal cusps are 

 small, but prominent and sharp, the posterior of the two being 

 the larger. 



Ohs. — I have been guided in referring this tooth to Otodus by 

 the absence of marginal crenulations to the cutting edge, as in 

 Carcharodon ; the . presence of the basal cusps distinguishing it 

 from Oxyrhina ; and by the extended or laterally spread-out 

 form, as compared with the vertical and upright aspect of the 

 teeth of Lamna. 



This tooth is in all probability from the upper jaw, and from 

 its arcuate outline somewhat posterior in position. The specimen 

 was carefully compared with a large series of similar teeth from 

 the Cretaceous rocks of England, and found to agree excellently 

 with Agassiz's species, especially that form represented in his PI. 

 32, f. 15, the present example being but slightly more arcuate. 



Locality. — Limestone at Kamileroy, Leichhardt River, North- 

 west Queensland (R. L. Jack, Esq. — Coll. Geol. Survey of 

 Queensland, Townsville). 



