102 



Naeella Tasmaniea, nom. mutand. 

 i\T. parva, var. Tasmaniea, Pilsbry, " Nautilus," 1895. 

 Frederick Henry Bay, Tasmania ( W. L. May). 



Cadulus (Gadilia) spretus, spec. nov. 



Shell small, of medium proportion, well-curved, variegated (in, 

 some specimens) with translucent and opaque-white rings and. 

 encircling bands. Surface smooth, with fine obliquely annular 

 grooves or lines, without traces of vertical striae. 



Apertures circular, transverse. Tube suddenly contracted 

 quite near the oral aperture, but exhibits a slight dilatation at 

 the end. 



Shell most like C. panamensis, Sharp and Pilsbry, but seems to 

 grow more rapidly, has greater breadth throughout, and is more 

 curved. 



Length of shell, 5*5 ; diameter of larger aperture, *7 ; of the 

 smaller aperture, -3 mm. 



Port Esperance, Tasmania, in 24 fathoms (W. L. May). 



Cyamium mactroides, spec. nov. 



Shell mactra-like, minute, equivalve, nearly equilateral, some- 

 what thick, smooth, and shining : of a whitish colour, and par- 

 tially brown -tinted, moderately convex. Surface concentrically 

 striated, obsoletely radially ridged, ventral and anterior margins 

 crenulated within. Umbos small, approximate, slightly directed 

 forwards, a little posterior. Dorsal line about equally inclined, 

 the anterior margin curved, the posterior margin truncatedly 

 rounded, ventral margin nearly straight. 



Hinge-line arched and relatively deep. Left valve with a 

 posterior marginal ligamental pit, in front of which is a central 

 cardinal tooth with two strong equal divaricating branches, and 

 an anterior oblique cardinal tooth. Right valve with two 

 diverging cardinal teeth, the anterior one bifid at the tip. 



Antero-posterior diameter, 2*05 ; umbo-ventral diameter, 1 *8 mm. 



Two pairs of valves, taken in life ( W. F. Petterd/). 



The reference of this little shell to Cyamium is because its 

 dentition agrees with the emended description of the genus as 

 implied by Bernard in Bull. Mus. Hist. ISTat., 1897, p. 311. 



Capditella delta, spec. nov-. 



Shell equilateral, subequivalve, trigonal, compressed with pro- 

 duced straight pointed umbones. The dorsal lines slope very 

 rapidly from the umbones which are in contact ; the post-dorsal 

 margin slightly arched, the anterior-dorsal straight ; the lunule 

 and escutcheon occupy deep elliptical depressions, angulated on 

 the margin. The ventral margin is arched, and is distantly 

 crenulated within. 



