27 



Eocene age, in the whorls being more angulate, the anterior canal 

 being more excavated, and in other minor features. 



Dimensions. — Length 9 mm ; breadth 3 mm. 



Form, and Loc. — Miocene : Muddy Creek, Victoria. 



G. 9309. Two specimens. 



Family CONID..S. 



Genus CONUS, Linnaeus. 



[Syst. Nat. ed. 10, 1758, p. 712.] 



Shell convolute, turbinate; aperture narrow and long, edentulous ; 

 columella smooth. 



An attempt to divide the Eocene fossils of this genus into 

 subgeneric groups based on observations made on living examples 

 of Conus, must always, the writer believes, be attended with great 

 uncertainty: for the genus itself had only just been established; 

 and although in a very unstable condition, it had not yet had full 

 opportunity of modifying, with development in diiierent directions. 

 No doubt, to a large extent, certain features of modern groups of 

 Cones were conceived in Eocene times, but they were not sufficiently 

 well differentiated to enable the species to be allocated clearly to 

 the subgenera as established on living species. Conus was pregnant 

 with evolutionary possibilities in the early Eocene. Nevertheless, 

 the writer has essayed a subdivision in spite of the difficulties and 

 uncertainties existing. 



Ti/pe. — Conus marmoreus, Linnaeus. 



Subgenus LEPTOCONUS, Swainson. 

 [Malacology, 1840, p. 312.] 



The author describes Leptoconus as follows : — " Shell light, 

 conic, sometimes striated ; spire elevated, acute, concave ; the 

 basal whorl carinated, detached, and sinuated above, and con- 

 tracted near the suture." Other characters which seem to be 

 fairly persistent in this group are the deeply-cut canal bordering 

 the suture and the more or less staged convolutions. 



Type. — Conus grandis, G. B. Sowerby. 



