Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/359

MOORE AUSTRALIAN MESOZOIC GEOLOGY. 251 lateral, moderately convex; umbones flattened, incurved over a large and rounded lunule ; anterior and posterior ends and dorsal margin rounded ; surface of the shell with broad irregular transverse bands of growth.

Fine examples of this shell are present in the Rev. W. B. Clarke's collection. It is one of the largest of the Australian bivalves, and appears to have attained a large size even for a Cytherea. The specimens are not in good condition. The largest example measures 6-1/4 inches in breadth by 4-1/4 inches in depth. The interior of one of the specimens was covered by Polyzoa and serpuloe, the casts of which are still seen in the matrix.

Locs. One example is from the Maranoa river, others being from Wollumbilla and one from the Gregory, north of Finnis Springs, on Stuart's route from Adelaide to Chambers Bay.

36. Cytherea gibbosa, sp. n.

A second species, much more convex and gibbous, with umbones much thickened, is present, but the specimen is too imperfect for description. It is from Wollumbilla.

37. GONIOMYA DEPRESSA, sp. n. Pl. XIII. fig. 6.

Shell ovately elongated, thin, flattened ; umbones close, depressed, mesial ; anterior end rounded ; the middle of the valves with a depression or fold from the umbo, which widens to the ventral margin, surface with broad curved rounded costae.

A single specimen, which has lost a part of the posterior end, represents this genus. The test is not well preserved, so that the entire ornamentation cannot be determined.

It is from Wollumbilla.

38. Leda australis, sp. n. Pl. XII. fig. 7.

Shell transversely ovate ; umbones anterior, contiguous, compressed ; anterior side rounded, posterior side longest, attenuated ; hinge-teeth small, numerous ; dorsal surface covered with numerous transverse striae.

Loc. Wollumbilla.

39. Lucina anomala, sp. n. Pl. XIV. fig. 4.

Shell nacreous, thin, equivalve, suborbicular, compressed; umbones mesial, close ; lunule small, distinct ; hinge-line much extended, on the posterior side rounded, on the anterior oblique and wing-like.

The surface of the shell possesses very close radiating longitudinal strife, decussated by equally close concentric striae which give the shell a faintly reticulated appearance. The longitudinal striae are more distinctly marked than is usual with the Lucinidoe.

Loc. Wollumbilla.

40. Lucina (?) australis, Sp. n. Pl. XIV. fig. 5.

Shell orbicular, or longitudinally ovate, nacreous ; umbones mesial,