‘ iit. 
: , i, 
186 RALPH TATE 
more than casts, but the comparative dimensions of the recent and 
fossil specimens are almost absolutely the same. 
Family Actmonip&. 
Genus Triploca, nov. 
Shell like Acteon, but with three revolving plaits on the 
columella. 
TRIPLOCA LIGATA, spec. nov., Pl. xi., fig. 7. 
Shell oval, thick, spirally linear-sulcate. Sulci impunctate ; 
whorls six and a-half, a little elevated at the suture and distinctly 
margined in front of it by an elevated band defined by an anterior 
impressed track ; suture impressed. The linear sulci are close 
together, but vary in their prominence, and are sometimes almost 
obliterated. Outer lip thickened internally, but is bevelled to a 
sharp entire edge ; columella triplicate, slightly reflected and pro- 
ducing a false umbilical fissure. Length 8, breadth 4. Locality— 
Eocene: Adelaide bore. 
Class LAMELLIBRANCHIATA. 
Family NucuLip. 
Genus Poroleda, nov. 
Examples :—Scaphula (?) elongata, Hutton, Trans. N. Z. Inst., 
XVII, p. 332, 1885. Poroleda lanceolata, Tate. 
Shell like Zeda, having an oblique internal cartilage-pit and a 
small pallial sinus ; the hinge-line (nearly straight) with a series 
of longitudinal imbricating teeth on each side. 
POROLEDA LANCEOLATA, spec. nov., Pl. xii, fig 6. 
Shell depressed, pellucid, shining, transversely elongate, con- 
centrically striate-ridged ; posterior side much produced and 
narrowly roundly-truncated at the end; hinge-line straight ; 
anterior side very short, rounded, rapidly sloping to about the 
middle of the ventral margin, thence sloping upwards but less 
rapidly to the posterior extremity. The post-dorsal area linear- 
lanceolate slightly flattened but not defined by a conspicuous 
