P(d(i('<nitolo(jji of tJic Older Tertiary. 329 



into the comparatively broad open canal. (Hiter lip thin and 

 eharp at the edge, columella smooth, straitrht, slender, and 

 tapering. 



Dimensions. — Average specimens have a length of about 33 

 mm., by a breadth of 10 or 11 mm. ; length of apertm-e and 

 canal 20 mm. ; greatest width of aperture, about 3.5 mm. 

 Specimens on the large side range from about 45 to 50 mm, 

 in length by a breadth of about 13 mm. ; while small speci- 

 mens range about 24 mm. in length bv 8 mm. breadth. 



Locality. — Common from the clays of the Cape Otway section, 

 near Point Flinders. — Jan Jukian.- — Eocene. 



Turbo hamiltonensis, sp. nov. (PI. XIX., Fig. 4). 



Description. — Shell turbinate, with a relatively elevated spire 

 in the adult, elevation not striking in the young, robust and 

 of medium size, consisting of about three convex whorls and 

 a smooth embryo of about a whorl and a half, whorls ornate 

 and strongly sculptured. Whorls convex, greatest convexity 

 approximately medial, posterior slope to suture more gradual 

 than anterior slope : suture well defined between the body 

 and penultimate whorls, not ascending, the suture becomes 

 less defined towards the embryo as the whorls overlap more, 

 giving the young forms a more depressed appearance. Earlier 

 Avhorls show three or four strong spiral threads on the upper 

 or posterior slope, the one next to but usually the two next 

 to the posterior 'suture sho\ving a beaded coronation ; this 

 character i's usually very indistinct or entirely absent from the 

 remaining threads, and is continued right on to the body-whorl, 

 where, however, it is not usually so clearly seen. The spiral 

 threads number about seven or eight on the penultimate whorl, 

 ten to greatest convexitj' on the body-whorl, varying in strength, 

 some being rather broad flattened bands, the interspaces being 

 narrow and deeply cut. Base (if the shell bearing about ten 

 strong threads which tend to become granulose near the um- 

 bilicus. Umbilicus small and rounded but deeply set. Aper- 

 ture orbicular with the outer lip bevelled off from the interior 

 to a sharp edge, posteriorly the inner lip is well defined by an 

 enamel pad reaching t/o and into the umbilicus, anteriorly the 

 columella end is somewhat patulous. 



