74 
Transactions of the Boyal Society of South Africa. 
structure, whilst the lunule is inconspicuous and much smaller. 
The specimen appears to be distinct from any shell yet described 
from either Africa or India, and although imperfect its notice on 
this occasion may lead to the acquisition of better material in the 
future when its determination may be made more secure. 
Locality. — Tributaries of the Manuan Creek. 
Genus MEEETEIX, Lamarck, 1799. 
Mem. Soc. Hist. Nat., Paris, 1799, p. 85. 
Meretrix cf. CAPERATA, J. de C. Sowerby. 
Plate VI., figs. 13-15. 
Venus caperata, J. de C. Sowerby, Mineral Conchology, 1826, vol. 6, 
pi. 518, figs. 1-3, p. 31 ; Orbigny, Pal. Fran9aise Terr. Cretaces 
Lamellibranchia, 1843-1846, pi. 385, figs. 9, 10, p. 445, and 
Prodrome de Pal6ontologie, 1850, vol. 2, p. 159 (No. 276). 
Cytherea caperata, Jukes-Browne and Hill, Cretaceous Eocks of 
Britain, Gault, &c. Mem. Geol. Surv. United Kingdom, 1900, 
vol. 1, p. 466. 
Observations. — There is only one example of this small form of 
Meretrix in the collection. It has both valves united and closed, 
and is probably allied to that originally described by Sowerby under 
the name of Venus caperata, from the Blackdown beds of England. 
The valves are considerably worn, although some remains of con- 
centric sculpture are still preserved, especially on the postero- 
umbonal region, which appear to represent the regularly cut ridges 
and sulcations characteristic of this species. In the ventral direction 
the surface is much smoother, erosive conditions having evidently 
destroyed the sharpness of the original ornamentation. In contour 
and dimensions this specimen compares most favourably with 
examples from Blackdown, except perhaps the oblique posterior 
margin may be relatively shorter. The valves, however, exhibit the 
same degree of convexity, a similar sub-trigonal outline, a small 
cordiform lunule, and an elongate, narrow escutcheon area in 
which the mineralised remains of the original ligament can be 
obscurely seen. 
Dimensions. — 
Length 27 mm. 
Height 25 „ 
Diameter 15 ,, 
According to Jukes-Browne's table of fossils in the Geological 
Survey Memoir the true caperata is restricted in Britain to the Am- 
monites rostratus zone of the Albian series, having been recorded from 
