184 RALPH TATE, 
known species. The genus is represented by one species in the 
Parisian Eocene. 
Length 3°75, width 1:75, length of aperture 1°75 (vix). 
Locality:—Eocene: Gellibrand River. 
Family Lirrorinip&. 
Genus Asella. 
RISELLA ALTA, spec. nov., Pl. xi., fig. 4. 
Shell conical ; whorls slightly concave; suture linear-impressed, 
margined on each side by a prominent spiral undulose rib, and 
presenting the appearance of being crossed by axially elongated 
nodulations ; the intervening area is traversed by two to four 
slightly undulose rounded threadlets, rendered somewhat nodulose 
by the intersecting oblique folds of growth. Base flat, the peri- 
phery flatly and thinly extended ; umbilicus minute ; there are 
from three to four concentric folds on the base. Length 5:5, 
breadth 6 mm. Localities—Eocene: Spring Creek and Muddy 
Creek. 
Family CyYCLosTREMIDZ. 
Genus Jinostoma. 
The species in the Australian Eocene referred to under Hthalia | 
belong to Tinostoma which is as well-represented in the European 
Eocene as in modern seas. 
Genus Adeorbis. 
This genus is represented by two or three species. Adeorbisaster, 
T.-Woods, is an Astralium ( Carinidea ). 
Genus Delphinula. 
This is represented by one if not two species in the Eocene at 
Muddy Creek, Gellibrand River, Fyansford and Mornington. 
Family TrocH1pD2&. 
Genus Cantharidus. | 
No species of T'rochus (sensu stricto) are known to me from the 
Australian Tertiary, those referred thereto belong to Cantharidus. 
