UNRECORDED GENERA OF THE OLDER TERTIARY FAUNA. 183 
slightly flattened at the posterior suture, suture channelled ; spir- 
ally flatly-sulcated, separated by narrower truncated elevated ribs, 
the sulci seven or eight on penultimate whorl (the posterior one 
double), with oblique distant threads; body-whorl with about 
fifteen spiral flat ribs, tessellated in the interspaces. 
Aperture large, oval, posteriorly angulated, slightly effuse basally; 
peristome entire; collumella arcuate, somewhat flattened, slightly 
reflected over the umbilicus, with a revolving median plait which 
does not extend to the free margin of the columella; umbilicus 
moderate, conspicuous. Length 7:5, width 4:5, length of aperture 
4-5 mm. 
Locality :—Eocene: Spring Creek, near Geelong (several 
examples). 
ISAPIS ELATUS, spec. nov., Pl. x., fig. 10. 
(Raulinia elata, Tate, MS.) 
Differs from the foregoing in its elongate bulimoid shape, non- 
canaliculate suture and closed umbilicus; the ornamentation is 
the same ; whorls five-and-a-half. Length 8-5, width 3°75. 
Locality:—Hocene: Muddy Creek, near Hamilton, Victoria. 
Family Lrriopipm. 
Genus Litiopa. 
LITIOPA PUNCTULIFERA, spec. nov., Pl. xi., fig. 9. 
Whorls four-and-a-half, of which the apical one-and-a-half are 
smooth ; the rest of rapid increase, concave, ornamented by trans- 
verse arched and spiral threadlets of about equal strength, which 
produce the appearance of punctures in the narrower interspaces. 
Aperture obliquely oval; outer lip thin, nearly straight posteriorly, 
slightly expanding in front; peristome entire; columella arched, 
slightly reflected to form a false umbilical chink, terminated at a 
little in front of the middle by an acutely angular notch which 
runs on the free margin into a short acute tooth-like projection. 
The species has the general outline of LZ. bombyx, but its punct- 
ate sculpture and sharp columella tooth separate it from the few 
