136 Frederick Chaj^man : 



Observations. — When complete, this type of tooth is seen to be 

 distinct from Lamna, Carcharias (Prio?iodon) or Car char odon. 

 From the former it differs in its serrated edges, and from the two 

 latter genera in the shape of the base and the presence of lateral 

 denticles. 



Occurrence. — Tertiary (Janjukian). Waurn Ponds, near Gee- 

 long; pres. by Mr. S. R. Mitchell (tooth consisting of crown and 

 part of base), W. of Kocky Point, Torquay. (A nearly perfect 

 specimen in excellent preservation, showing the crown and two 

 lateral denticles, with a part of the base.) From the collection of 

 the late Dr. T. S. Hall, M.A. 



Carcharoides tenuidens, Chapman. (Plate IX., Fig. 3.) 



cf. Carcharias {Prionodon) acutus. non Agassiz, Chapman and 

 Pritchard, 1904, Proc. Roy. Soc. Vict., vol. XVII. (N.S.), pt. I., 

 p. 274. 



Carcharoides tenuidens. Chapman, 1913, Victorian Naturalist, 

 vol. XXX., pp. 142, 143, and woodcut. Idem, 1914, Australasian 

 Fossils, p. 270, fig. 131a. 



Description. — Holotype. Tooth of slender habit. Root slightly 

 ■arched and moderately stout. Crown acutely triangular, flattened 

 on the outer face near the junction with the root, and otherwise 

 "depressed convex; inner face roundly convex; edge view showing a 

 wide recurvation of the lateral line, as in Odontaspis. Edge 

 crenulate, with blunt serrae. Lateral denticles well developed, sharp, 

 and turned towards the crown. 



Dimensions. — Total length from base to apex, 20.25 mm. Ex- 

 treme width at base of root, 12 mm. ; thickness, 4.5 mm. ; width of 

 crown at junction with root, 7.25 mm.; thickness, 3.75 mm. 

 Length of lateral denticle, 3.75 mm. 



Observations. — The serrated crown from Waurn Ponds described 

 by Dr. Pritchard and myself in 1904, and doubtfully referred to 

 Carcharias (Prionodon) acutus, Ag. appears to belong to the above 

 species, with which it agrees in its narrow crown and acute 

 apex, as distinguished from that of the preceding species, C. fotu- 

 serratus, which has a broader crown. 



Occurrence. — Tertiary (Janjukian). Waurn Ponds Quarry. 

 Type specimen collected and presented by Mr. J. F. Mulder. An 

 imperfect tooth (crown only), from J. F. Bailey coll.; same locality. 



