165 
Interior of Shell.—Porcelaneous, with raised riblets on 
posterior part of valve, sinus shallow and wavy, sutural 
laminze very short. 
Girdle.—Covered with irregular appressed  spinelets, 
coarser towards the outer margin. In curled specimens these 
spines are erect, creamy-white with red spashes. 
Measurement.—10 x5 mm. 
/1ab.—Dredged by Dr. Vereo in Spencer Gulf. One 
specimen was found by the writer on the north-west coast 
of Tasmania, and another from the same locality is in the 
possession of Mr. Basset Hull. 
Remarks.—\ have had considerable difficulty in deter- 
mining the genus of this shell. It has pectinated teeth and 
eyes like Vonicia, but the girdle is not leathery, nor are the 
valves so polished. It may be a Chatopleura. The descrip- 
tion is repeated, as the dredged South Australian specimens 
differ from the account given by Dr. Torr in the Proc. Roy. 
Soc., Tasmania. No eye-dots can be seen in the Tasmanian 
specimen, ; 
Yarachiten 
56. kepidopleurts pelagicus, sp nov. Pl. v., figs 2u-/, 
General Appearance.—Ovate, decidedly arched and 
strongly carinated. Side slopes straight. The shell gradually 
tapers towards the tail valve. The valves overlap the girdle. 
Colour.—Uniform, pale sulphur-yellow; the girdle has a 
slightly deeper shade, almost brown when dried. 
anterior Valve.—Broader than the median valves. It 
has three or four concentric grooves or growth markings 
parallel to the girdle, crossed by a number of minute stria- 
tions converging towards the apex. The interior is pearly- 
white. No dentition nor sutural laminz. The posterior edge 
of the valve is serrated. 
Median Valve.—The lateral area is gradually elevated 
above the central area. The whole of the valve is covered 
with minute tubercles in longitudinal rows in the dorsal and 
pleural areas. Under the microscope, these appear like 
strings of beads. The rows are transverse in the lateral areas. 
The sutural plates are diminutive and semi-transparent, the 
sinus very broad. The posterior edge of the valve is ser- 
rated. Interior pearly and semi-transparent, the striations 
of the tegmentum distinctly shows through. 
Posterior Valve.—Mucro median elevated, with concave 
slope to girdle. Pustulose lire converge to the mucro. 
Sutural plates delicately diminutive. 
Girdle.—Leathery and spiny to the unaided eye. Under 
1}-in. lens it is covered with minute specules. 
File , 
