Tertiary.-] PALvEONTOLOGY OF VICTORIA. \_Molhisca. 



Plates XXVIII. and XXIX., Fig. 1. 

 CYPR^A (ARICIA) GIGAS (McCoy). 



[Genus CYPRyEA (Lin.) (Sub-kingd. MoUusca. Class Gasteropoda. Order Pectini- 

 branohiata. Fain. Cyprasids.) 



Gen. Char. — Shell ovato-obloug; spire very short, or entirely corered by the body whorl; 

 back rounded ; inner and outer lips inrolled ; aperture narrow, as long as the shell, reflected at 

 both ends, transversely toothed and ridged on each side. 



Sub-geiius. — Aricia (Gray). Surface highly polished ; gibbous above ; flattened, thickened, 

 and dilated at the sides below; spire covered; aperture straight, narrow ; outer and inner lips 

 callou.s. thickened, wide, dentated. 



Suh-genti.i. — Trivia (Gray). Small, globose ; surface tubercul.ited or covered with narrow, 

 prominent transverse ridges ; spire concealed ; aperture narrow, both lips denticulated.] 



Desription. — (See second Decade.) 



Additional locality — In Oligocene Tertiary clays near mouth of 

 Gellibraud River. 



Explanation of Figure. 

 Plates XXVm. and XXEX. — Fig. 1, ventral view of large specimen, natural size. 



Plates XXVIII. and XXIX., Figs. 2-2b. 

 CYPR^A (ARICIA) EXIMIA (Sow). 



Description. — Pyrifbrm ; back ventricose towards the posterior side, and 

 abruptly and obtusely subtruncate to sliglitly depressed spire of two convex turns, 

 partially exposed; "-ladually ta])pring- to the anterior end into a long' narrow slig-htly 

 raised canal supjiorted by a tiiang-ular straight-edg-ed extension of the ba.se; two 

 large compressed obtuselj^ rounded tubercles separated by a deep depression, one on 

 each side of the dorsal aspect of the base of the anterior canal; posterior canal 

 shorter than the anterior one, more or less reflexed, supported below by a depressed 

 extension of the flange or base with an outwardly convex outline. Under side 

 rounded in the middle, thickened with a narrow flattened extension at sides of 

 anterior and ])osterior canals. Outer lip inflexed, strongly toothed within, teeth 

 larg-pst and extending- slightly over base for J the length of mouth in front of the 

 middle ; teeth behind the middle smaller. Base from inner lip with a broad band 

 of deep sulci, with broad intervening ridges extending fr om teeth. Length of large 

 typical specimen about 4 inches ; proportional width, ^^j^ij; height, -j4j'„ ; diameter of 

 spire, 3^5 : length of anterior canal, -ijj%; length of jiosterior canal, ^'jAy. 



Refernce.— Sow. in Strzel., N. S. W., p. 296, t. 19, fig-s. 1-3. 



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