Annals of the Transvaal Museum 
143 
lobe-line of the new form and that of P. Velledae and allied forms. In the 
Indian forms the external lobe is very much shorter than the first lateral lobe, 
whereas in the Pondoland ammonite the two lobes are nearly of the same 
size. There is close agreement between the lobe-line of our form and that 
of Phylloceras sp. mentioned by Woods from Pondoland (“The Cretaceous 
Fauna of Pondoland," Ann. S. Afr. Mus. vol. iv. Pt. vn. PI. XLI, fig. 4). 
There is, however, difference in the shape and the ribbing of the shell. There 
is also a great resemblance between the suture-line of P. Roger si Kitchin 
and that of our form. The shells differ, however, in shape and ornamentation. 
The specimen is imperfect and wholly septate. One side of the last whorl 
has weathered away. 
Gaudryceras amapondense n.sp. PI. XXIV, figs. 4, 5. 
Shell discoidal, compressed. Sides of whorl slightly convex and convergent 
towards the rounded periphery. Last whorl rather rapidly increasing. The 
umbilicus is large, the umbilical surface fairly steep and the umbilical margin 
strongly convex. Whorls higher than broad and covering about half of the 
flanks of the preceding whorl. 
Whorls ornamented with low ribs, which are narrow within the umbilicus 
and become broader towards the periphery. Between these other ribs are 
intercalated, which are only faintly visible at the umbilicus. Ribs of unequal 
breadth and separated by unequal distances. Both ribs and interspaces are 
covered by numerous fine ribs. The last whorl shows four ribs, at a distance 
of about 90 degrees from each other, which are much broader and thicker than 
those in their immediate vicinity. One of these ribs had to be removed in 
studying the suture-line and was seen to correspond with a constriction on the 
internal cast. The last of these ribs is immediately preceded by three others, 
which are also broad and thick and separated by broad interspaces. The 
umbilical portion of all the ribs is concave forwards, on the sides they are 
convex forwards and near the ventral border they are again concave forwards. 
Their ventral portion was not seen. Inner whorls covered with finer ribs; 
here and there is a coarser one followed by a deep groove. 
The suture-line has not been seen completely. That which is visible con- 
sists of a portion of the first lateral lobe, both lateral saddles, one auxiliary 
saddle and a portion of another. The remaining space between the visible 
portion of the last saddle and the umbilical suture is slightly broader than the 
breadth of this portion. The auxiliary lobes and saddles become smaller 
towards the umbilical suture and run slightly backwards. Further detail 
may be gathered from the figures. 
Measurements : 
Diameter ... ... ... ... 109 mm. (1} 
Height of last whorl ... ... ... 47 ,, (0*43) 
Thickness of last whorl ... ... perhaps 41 ,, (0-38) 
Height of penultimate whorl ... about 20 ,, (0-18) 
Thickness of penultimate whorl ... ... 9 ,, (0-08) 
Diameter of umbilicus ... ... ... 28 ,, (0-26) 
As the thickness over the longest diameter cannot be accurately given, the 
three first measurements are again taken at about 90 degrees back from the 
anterior end. 
Diameter ... ... ... ... ... 88 mm. (1) 
Height of last whorl ... ... ... 38 ,, (0-43 
Thickness of last whorl ... ... ... 29 ,, (0*33 
