Victorian Marine Mollusca. 105 



the shell, much curved, with greater width at anterior extremity. 

 Outer lip somewhat thickened, smooth internally, and projecting 

 beyond a slightly flattened summit. Corresponding with the outer 

 lip, the labium is pronouncedly convex, bearing numerous plica- 

 tions, which extend almost the entire length of the aperture, becom- 

 ing faint posteriorly. The anterior plait is conspicuous and well 

 separated from the remainder. 



Dimensions of Type. — Length, 3.50; breadth, 2.50 mm. 



Locality. — Dredged Western Port, 8 to 10 fathoms. 



Obs. — This strong little species resembles at least two of our 

 Southern Australian forms, M. halli, Pritchard and Gatliff, and 

 M. inaequidens, May. From the former it is separable by its 

 flattened summit and more triangular shape, and from the latter 

 by its less cylindrical contour, its greater solidity, and in the 

 disposition of the plications, which are stronger in the new species. 



Type in Mr. C. J. Gabriel's collection. 



Lepton frenchiensis, sp. nov. (PI. VIT., Figs. 3 and 4), 



Shell thin, creamy white, semi-transparent, quadrately oval, sub- 

 equilateral. Umboes fairly prominent, projecting slightly beyond 

 the dorsal margin, which is arched. Ventral margin almost 

 straight, while a decided roundness is seen anteriorly and pos- 

 teriorly. The surface of shell is irregularly, finely, concentrically 

 striated. The valve is sufficiently transparent to discern from the 

 exterior the pallial line, and adductor scars. Hinge normal. 



Dimensions of Type. — Anterior-posterior diameter, 3; dorsal- 

 ventral diameter, 2.25 mm. 



liocality. — Dredged Western Port, 8 to 10 fathoms. 



Obs. — A single valve is selected as type, joined valves not having 

 been taken. The species bears some resemblance to L. australe, 

 Angas, firstly, in contour, and, secondly, in lacking the charac- 

 teristic shagreen sculpture of the genus. The greater depth propor- 

 tionately, in having more rounded beaks, and the lesser dimensions 

 being the chief points of difference. 



Type in Mr. C. J. Gabriel's collection. 



EXPLANATION OF PLATE. 



Fig. 1. — ^larginella problematica, sp. nov. 

 ,, 2. — Eulima immaculata, Pritchard and Gatliff. 

 ,, 3, 4. — Lepton frenchiensis, sp. nov. 

 The figures are variously magnified. 



