Fig. 1 
Fig. 2 
Fig. 3 
PLATE XVIII. 
Eurydesma cordatum, Morris. 
. Lateral view of the right valve of the specimen Plate XVTI, e.xhibitiug in a still more 
marked manner the projection of the left umbonal region ; the general cordate 
outline and posterior e.xtension of the valves is also in evidence. 
Eui’ydesma hobartense, Johnston. 
. Testiferous left valve. 
Df)rsal view of the united valves displaying an abnormal width between the umbones, the 
byssal groove under the right umbo, an unusual rugosity in the flattened lunular 
depression, and inequality of valves. 
Localities. 
Fig. ]. Allandale, near West Maitland. 
Figs. 2, 3. Maria Island, Tasmania. 
