Victorian Fossils, Fart XXI. 41 



in the photograph by Dr. Hall, is due to an interesting minera- 

 logical change set up in the tooth during early fossilisation and sub- 

 sequent weathering. The narrower root axis as compared with the 

 •crown is caused by phosphatization of the dentine and its consequent 

 hardening, whereas the surrounding cement, being of a softer tex- 

 ture, has subsequently been removed by the resortment and disturb- 

 ance of the deposit before final sedimentation. The surface of the 

 phosphatized axis of the tooth is polished like that of the mineralized 

 tympanic" bones found associated in the same beds. The grooved 

 ■ornament of the enamel of the crown of the tooth is exactly similar 

 to typical incisor teeth of r.wiU.itisoni . 



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

 long. Presented by the Rev. C. S. Y. Price. 



A new locality for P.wilki/isoni may here be noticed, namely Leigh 

 River, near Shelford, where a fairly comj^lete incisor was found and 

 presented to the National Museum by Mr. J. H. Young, of Meredith. 

 This discovery of a typical Miocene species helps to correlate the 

 Shelford beds with the Janjukian series. 



Fam. Delphinidae. 



Genus Steno, Gray. 



Steno cudmorei, sp. nov. (Plate IV., Fig. 5). 



Descr'iption. — Tooth, convexly curved and twisted, more or less 

 circular in section. Root more than twice the length of the crown, 

 closed at the base and swollen or bulbous just beh^w the base of the 

 crown. Crown conical, curved, with a moderately sharp apex; 

 colour dark brown increasing in depth to black at the base; surface 

 roughly scored by fine irregular vertical furrows. The cementum 

 impinges over the base of the crown, and at 2.5 mm. below the crown 

 is cinctured by a brown stain, probably marking the upper edge of 

 the alveolus. The root is ochreous brown to yellow, and irregularly 

 wrinkled and furrowed, especially towards the base. 



Measurements. — Length of tooth, measured along tlie f)uter side, 

 23 mm. (crown 7 mm.; root, 16mm.); width of crown at base, 4 

 mm. ; Avidest part of root, near distal end, 5 mm. 



Observations. — At first glance this tooth might be thought to show 

 alliance with the incisor of Parasqiialodon , which it resembles in 

 general shape and in the vertically rugose crown. The root in the 

 present tooth, however, is closed, Avhilst that of the incisor of Paras- 

 qualodon is open and deep. Further than this, ParasquaUdon has 



