I 
,/ 
203 
Strzelecki and W. B.' Clarke. Mr. W. B. Clarke found it near Stroud on the 
Kama, in the Ichthyodorulite Bange, between the Hunter and Bonchel 
Rivers. Messrs. Dana and McCoy have also found it in the Illawarra District. 
Dioisioii — MOLLUSCA. 
LAMELLIBRANCHIATA. 
Genus — SCALDIA, de RijckhoU. 
1. ScALDiA ? DEPRESSA, L. G. de Koniiick. 
PI. XV, Fig. 6. 
This is a slightly transverse shell, a very little broader than long, suh- 
oval, and much depressed anteriorly. Its beaks are very small, and placed 
a little in front of the centre of the hinge line. The edges are sharp ; the 
anterior is semi-elliptical, while the posterior is slightly truncated. The 
posterior part of the valve is distinctly separated from the anterior and middle 
j)arts by a depression originating at the beaks, and passing towards the ventral 
margin, crossing the shell obliquely. The test is very thin ; its surface is 
ornamented only wuth line concentric lines of growth. 
Dimensions. — The length is thirty-four, the breadth sixteen, and the 
thickness eight, millimetres. 
Relations and, Differences . — This species is easily distinguished from 
its congeners by its thinness. The only specimen supplied me showed the 
impression of the hinge, and thus allowed me to state its genus with 
certainty. 
Dorizon and Localities. — It was found in a greyish sandstone at 
Buchan on the Gloucester. 
SCALDIA ? LAMELLIFERA, L. G. dc Konhick. 
PI. XY, Fig. 7. 
This shell is small, very nearly orbicular, depressed, with small, straight 
beaks placed nearly in the middle of the hinge line. An oblique depression, 
commencing at the beak, is perceptible on the posterior part of the valves. 
2 E 
