Cretaceous Gastropoda, and Pelecypoda from Zulidand. 79 
As will be seen from the above measurements, the chief difference 
between our specimen and Lartet's type from the Holy Land is its 
smaller size. According to Blanckenhorn, the species is found in 
Syria in the Buchiceras zone of the Cenomanian series, but that the 
type from the Holy Land belongs to a higher horizon between the 
Cenomanian and Senonian. 
Locality. — Tributaries of the Manuan Creek. 
Pholadomya vignesi, Lartet emend. Blanckenhorn. 
Plate VI., figs. 3-6. 
Pholadomya vignesi, Lartet, Explor. Geol. de la Mer Morte, 1877, 
pi. xi., fig. 9, p. 126 ; Blanckenhorn, Beitrage zur Geologie 
Syriens, 1890, pi. 5, figs. 14, 16, 17, p. 94. 
Gymella [Pholadomya ?) vignesi (Lartet), Whitfield, Bidl. American 
Mus. Nat. Hist., 1891, vol. 3, p. 386 (quoted in list without 
explanatory text). 
Pholadomya vignesi, Kossmat, Denkschr. K. Akad. Wiss., 1902, 
vol. 71, pi. 4, fig. 9, p. 55 (Semha Island, near Socotra). 
Observations. — From the number of specimens in the collection, 
this form of Pholadomya appears to be a characteristic fossil of Zulu- 
land. The valves are mostly in a fair state of preservation, especially 
as regards external features, the typical granulations of the costse 
being well expressed. In longitudinal measurement they vary from 
20-35 mm. The full dimensions of two right valves showing these 
extremes of size, give the following results : — 
Largest. Smallest. 
Length 35 20 mm. 
Height 30 17 „ 
Depth 15 8 ,, 
The valves are trausversely sub-oval, strongly convex or arched, 
inaequilateral, and having antemedian incurved umbones. Anteriorly 
the sides are short, rounded, and ventricose, whilst the posterior 
regions are produced and depressed. The sculpture is made up of 
closely arranged radial costse (18-26) and concentric ridges, bearing 
numerous small rounded granulations, which with age appear to 
become flattened and more or less transversely elongate. On the 
extreme anterior side in the neighbourhood of the lunule the radial 
costae are very obscure or absent, and they are altogether wanting on 
the posterior area, which, with the exception of extremely fine con- 
centric lineations, has a nearly smooth surface. The concentric 
ridges are more accentuated on the umbonal region, the radial sculp- 
ture becoming stronger as the shell advances in size. A certain 
