Cretaceous Gastropoda, and Pelecypoda from Zululand. 19 
which is a Naticiform shell with whorls channelled above and possess- 
ing a deep umbilical cavity with no evidence of a callus either on 
the columella or base. This genus is quite characteristic of Upper 
Cretaceous rocks, having been recorded from the United States, 
Europe, Africa, and India. 
Mr. Etheridge, jun., has figured some imperfect specimens of this 
genus from the Umkwelane Hill deposits (Anderson's Second Eeport 
of the Geol. Surv. of Natal and Zululand, 1904, pi. 2, fig. 32, pi. 3, 
fig. 1, p. 88), which he determines as Gyrodes (?) sp. indet., but as 
the important umbilical characters are not shown it is scarcely pos- 
sible to use such material for purposes of comparison except it 
might be observed that the specimens are much smaller than the 
form now described, although having the oblique sculpture lines 
and a widely channelled suture. 
In a similar way Mr. Woods has figured two fragmentary speci- 
mens as Gyrodes sp. (Cretaceous Fauna of Pondoland: Annals South 
Africaii Museum, 1906, vol. 4, part 7, pi. 38, figs. 9, 10, p. 317), which 
were collected in the Cretaceous deposits of Pondoland, but these 
differ in having a less developed umbilical cavity, besides showing a 
relatively greater width of body-whorl. MM. Thomas and Peron 
have described some internal casts from the Cenomanian deposits of 
Algeria and Tunis (Desc. Moll. Eossiles Terr. Cretaces Tunisie, 
Explor. Scientif. Tunisie, 1890, part 1, pi. 19, figs. 19-21, p. 53), 
under the name of Natica suhexcavata, which undoubtedly may be 
referred to Gyrodes, but which are easily distinguishable from the 
Zululand shell by the possession of a narrower and more produced 
body-whorl, although exhibiting quite as prominent an umbilical 
cavity. It is interesting to note also in connection with N. suh- 
excavata that the authors acknowledge its resemblance to Michelin's 
European species, Natica excavata, a characteristic Albian fossil of 
France (see Orbigny : Paleontologie Fran9aise. Terrains Cretaces. 
Gasteropoda, 1842, pi. 173, figs. 1, 2, p. 155), which is an ex- 
cellent example of Gyrodes, but with an apparently less developed 
spiral region and a more oblique aperture than is observed in the 
present shell. An Indian form has, however, been described 
by Stoliczka, which perhaps is more closely related to the 
shell in question than those previously mentioned ; this is Gyrodes 
pansus, which ranges throughout the three divisions of the Creta- 
ceous strata — the Utatur, the Trichinopoly and the Ariyalur 
(Cretaceous Gastropoda, Southern India, Pal. Indica, 1868, pi. 22, 
figs. 9-13, p. 305). The general contour is very similar, so also is 
the ornamentation, that is if the small thick tubercles of the African 
shell on the sab-angulate shoulders be regarded as crenulations. It 
