339 



finely spiral striie and inconspicuous transverse striae ; the sulci 

 on each side of the central rib are of equal breadth, but the 

 anterior rib is separated from the suture by a distance less than 

 that which intervenes between it and central rib, whilst the 

 posterior rib is separated from its corresponding suture by a 

 distance greater than the breadth of the medial sulcus. Last 

 whorl with four keels, truncately angular at the periphery ; base 

 spirally flatly ribbed and interstriated. Aperture quadrate ; 

 outer lip imperfect ; the stria' of growth deeply roundly arched 

 between the anterior and posterior keels. 



Dhneiwions. — Length, 46 ; breadth, 12. 



Locality. — Eocene : Table Cape ( R. M. Joltnston, one ex- 

 ample I) : Cheltenham (not uncommon !) ; Camperdown ! ; Bel- 

 mont ! ; (?) well-sinking, Murray Desert I . Miocene : Gipps- 

 lancl Lakes (very abundant !). 



This species is distinct from the few living species, which are 

 consi3icuously three-ribbed, by shape, ornament, and the unsym- 

 metrical position of the revolving keels. T. tricincta, Hutton, 

 Pliocene and Miocene in New Zealand, has three unequal keels 

 and the wliorls more convex. 



8. Tupritella eonspieabilis, -^per. nor. Pi. viii., fig. 7. 



Shell similar to T. tristira, but differs in its ornamentation. 

 The spire is acuminately attenuated ; the embryonic whorls are 

 succeeded by two or three convex whorls, then follow three or 

 four, which are convex posteriorly, but abruptly declining to the 

 anterior suture ; the anterior keel becomes stronger, and on the 

 posterior area threads appear, increasing in number with the 

 revolution of the spire. Anterior whorls have a high rounded 

 rib, situated in the anterior one-third, separated by a wide sulcus 

 from the posterior one-half, which is ornamented by six to ten 

 threads alternately large and small ; the anterior-half, including 

 the keel, is spirally striate. 



Locality. — Eocene : Spring Creek 1 . Miocene : Gippsland Lakes I . 



Though associated with T. tristira at the latter locality, and not 

 with it elsewhere, yet as there are no decided intermediate stages, 

 I have somewhat reluctantly considered it a distinct species. A 

 varietal form (pi. ix., fig. 6), if not a distinct species, occurs 

 abundantly at Spring Creek, which differs by less prominent 

 keel. It makes some approach to that variety of T. runcinata, 

 in whicli the front keel is conspicuously elevated, but the whorls 

 are more quadrate, the keel truncated on the edge ; whilst the 

 spiral strii^ are fewer and not wavy-interrupted. 



9. TurPitella aCPieula, s/jec. nor. Pi. vlil., fig. 4 ; pi. ix., figs. 4, 7, 8. 



Shell very acutely lanceolate-turreted ; whorls twenty, apex 



mammillary of two narrow convex turns, early posterior whorls 



X 



