46 Transactions of the Eoyal Society of South Africa. 
Observations. — This specimen is represented by a convex natural 
cast of a right valve embedded in matrix showing external features, 
but which is marginally imperfect so far as the posterior and part 
of the ventral regions are concerned. In general aspect it shows a 
wonderful resemblance to a small flint example in the Sowerby 
collection at the British Museum, determined as I. hrongniarti, of 
Mantell, 1822 — a species which may undoubtedly be included in 
Parkinson's lamarchi of an earlier date. With only one specimen 
for comparison, and that somewhat imperfect, it would perhaps be 
premature to consider the Zululand shell as synchronous with the 
British species, although possessing an exactly similar horizontal 
hinge-line, a steep and nearly perpendicular anterior side, and with 
the same character of curvature in the details of the concentric 
sculpture, with the exception that intermediate striations are not 
apparently present. 
Further, certain similarities can be traced with Mr. Etheridge's 
Melina andersoni from the Cretaceous rocks of Umkwelane Hill (W. 
Anderson, ''Second Eept. Geol. Surv. Natal and Zululand," 1904, 
pi. 2, figs. 7-10, p. 73), but such differences as an excavation in 
front of the umbo with a subsequent rounding of the anterior margin, 
appear to be of sufficient importance for the separation of that 
species from the present form. Much the same characters would 
also distinguish it from Inoceramus volvuimhonatus of E. Etheridge, 
from the Cretaceous beds of the Umsinene Eiver (W. Anderson, 
" Third and Final Eept. Geol. Surv. Natal and Zululand," 1907, pi. 2, 
figs. 1-6, p. 73), a species which is of greater height than length, and 
furnished with high and prominent umbones. 
It may be also mentioned that the present shell can be distin- 
guished from I. exjjansus of Baily from the Cretaceous of Pondoland 
(near Umtamvuna Eiver) by its much smaller size and relatively more 
convex valve, and the absence of concentric striae on the surface 
of the sulcations {Quart. Journ. Geol. Soc, 1855, vol. xi., pi. 13, 
fig. 5, p. 462, and H. Woods, Annals South African Museum, 1906, 
vol. 4, part 7, p. 299). 
This fossil is associated in the same matrix with the body-whorl 
of Dreijanocheilus sp. and a Serpula-tuhe. 
I have ventured to associate with this shell the name of M. Paul 
Choffat, in recognition of his important researches on the Cretaceous 
palseontology of various parts of Portuguese Africa. 
Locality. — Tributaries of the Manuan Creek. 
