44 Trmisactions of the Boyal Society of South Africa. 
rather unusual compression at the sides, as well as a pronounced 
medio-longitudinal inflation. The sculpture lines are purely con- 
centric, no radial ornamentation being visible. The specimen may 
be compared with Lithodomus suh-cylinclricus of Stoliczka (Creta- 
ceous Pelecypoda, Southern India, Pal. Indica, 1871, pi. 23, figs. 
18-19, p. 376), from the Utatur beds of Southern India, although 
differing in possessing a slight curvature at the dorsal margin and in 
having a latero-ventral compression, besides being of greater length. 
The concentric lineation also is perhaps less regular than in the 
Indian shell. Again, the species need not be mistaken for the 
European Cenomanian form, Lithodomus rugosus, Orbigny (Pal. 
Fran9aise, Terr. Cretaces Lamellibranchia, 1843, pi. 346, figs. 1-3, 
p. 294), which is of greater length, more cyliadrical, and differing 
in sculpture by the addition of radial striations on the antero-ventral 
region. 
Locality. — Tributaries of the Manuan Creek. 
Family AYICULID^. 
Genus PINNA, Linnagus. 
Systema Naturae, 1758, edition X., p. 707. 
Pinna cf. complanata, Stoliczka. 
Plate IX., figs. 3 and 4. 
Pinna complanata, Stoliczka, Cretaceous Pelecypoda, Southern 
India, Pal. Indica, 1871, pi. 24, figs. 3, 4, p. 384. 
Observations. — This is a form closely related, if not identical with, 
P. complanata, as described and figured by Stoliczka from the Trichi- 
nopoly group of India. Parts of the nacreous layer of the specimen 
are still preserved, otherwise there is very little of the original shell 
structure intact, the fossil being more or less in the nature of a cast. 
On the dorsal region are a few shallow, longitudinal sulcations radi- 
ating from the apical region of the shell, and which are, therefore, not 
quite parallel with the hinge margin ; they are quite smooth and 
show no transverse lineations, which characterise some species, 
resembling in this manner what obtains in the form from India. 
In general contour and size there is also a similarity of design 
with Stoliczka's species. The dorsal and ventral lines diverge at 
much the same angle, the valves are elongately trigonal, the dorsal 
margin being perfectly straight and the ventral having an inward 
central curvature. 
As so frequently happens with this genus, and especially fossil 
forms, the valves show a median longitudinal fracture or fissure, 
