142 
Annals of the Transvaal Museum 
DESCRIPTION OF SOME CRETACEOUS 
AMMONITES FROM PONDOLAND 
By Dr E. C. N. van Hoepen, M.I. 
With three plates. 
The ammonites here described were purchased with other fossils from Mr J. 
Venter, who collected them on the coast of Pondoland, near the mouth of 
the Umzamba river. 
Phylloceras umzambiense n.sp. PI. XXIV, figs, i — 3. 
The whorls of the discoidal shell are strongly involute and higher than 
broad. The greatest thickness of the whorl lies internal to the middle of the 
flanks. The external surface is broadly convex and the sides are slightly 
flattened. The umbilicus is narrow and deep, the umbilical surface moderately 
inclined. 
The ornamentation consists of numerous, crowded, thin, wire-like ribs. 
These ribs commence deep down in the umbilicus and, on passing on to the 
flanks, swerve forwards; from near the midde of the flanks to the periphery 
they are practically straight and directed slightly backwards. The outer end 
of the ribs may be slightly stronger than the inner end, but on one portion 
of the shell the ribs are stronger on the internal half of the flank than on the 
outer. Short ribs, starting at or near the middle of the flanks and running 
across the periphery, are regularly intercalated between the long ones. Some- 
times, though very exceptionally, these ribs start nearer to the umbilicus. 
They all run practically straight to the periphery, in the same direction as the 
long ribs. The surface of the shell is weakly corrugated near the umbilicus. 
The corrugations are low and short, disappearing before reaching the middle of 
the flanks. They also disappear on the umbilical surface. Their curvature is 
the same as of the ribs in this region. Their breadth is such that they bear 
from four to six ribs. 
The lobe-line is phylloid. The anterior terminations of the saddles are 
broad and well rounded. This fact, however, is only seen well through the 
transparent shell; if this be removed with acid the lobe-line seems to suffer 
easily. In general the lobe-line agrees very well with that of Phylloceras For- 
besianum d’Orb sp. The siphonal saddle, however, is not so sharply pointed 
as in that species. The external lobe has nearly the same length as the first 
lateral lobe. The external saddle and the first lateral saddle are both sym- 
metrically divided by a secondary lobe. The second lateral saddle shows three 
anterior terminations. The auxiliary saddles, six in number, become rapidly 
smaller. 
Measurements : 
Diameter ... ... ... ... 44mm. (1) 
Height of last whorl ... ... ... 27 ,, (o*6i) 
Thickness of last whorl: actual 16 mm. was probably 17 ,, (0-39) 
Width of umbilicus ... ... ... 2 ,, (0-05) 
Superficially there is some resemblance between this form and Phylloceras 
Nera Forbes sp. The Indian species, however, has a series of radial sulci, 
around the umbilicus, which are apparently absent in our form. The radial 
corrugations of our form are apparently absent in P. Nera. The new species is 
also relatively thicker than P. Nera. There is a great difference between the 
