146 Annals of the Transvaal Museum 
The actual diameter of the second specimen is 82 mm. As the other measure- 
ments could not be taken on this diameter it was thought better to take them 
over that of 62 mm., whereby they would all be on one line. 
The new form shows great resemblance with species of the group Holco- 
discus Aemilianus Stol. It differs from H. Kandi Stol. sp. by being more 
involute, by the different arrangement of the ribs and their comparative 
straightness. H. madrasinus Stol. sp. has a last whorl, which is twice as high 
as broad. It is also more involute and its constrictions are more numerous. 
In H. karapadensis Kossmat the ribs are flattened on the flanks and on the 
periphery, while the sulci are directed much more forwards. H. buddhaicus 
Kossmat shows great resemblance in the ornamentation, but differs in the 
fact that its whorls are broader than high. 
Named after Faku, a former paramount chief of the Pondo tribe. 
Holco discus africanus n.sp. PI. XXVI, figs. 3 — 5. 
Shell discoid al. Last whorl higher than broad . Greatest thickness of whorls 
at the umbilical edge. Sides of whorl nearly flat near the umbilical margin, 
becoming more and more convex towards the periphery. External surface 
strongly convex. Umbilical surface low and very steep. Involution moderate, 
about one-half of the preceding whorl being embraced. 
Umbilical surface smooth. Sides of whorl covered with numerous narrow, 
rounded ribs, which are strong on the sides but ver}^ faint at the periphery. 
Most of the ribs emanate from tubercles on the extreme umbilical margin. 
The tubercles have mostly a more or less radially directed edge; the ribs 
emanate from them by twos, while a rib originates at the side of the tubercle 
in front and behind of this pair. Practically, therefore, there are four ribs 
to one tubercle. Near an old mouth groove this arrangement may become 
slightly irregular, through the presence of an extra rib. Ah the ribs have the 
same relative length. At irregular intervals the whole whorl is traversed by 
a deep groove, which is bordered in front by a thick ridge. Near the periphery 
the hinder border of the groove is formed by an equally strong rib, but on the 
flanks this rib is very much weaker. The course of the groove is sinuous; at 
the umbilical edge it is concave forwards, near the middle of the flank it is 
convex forwards and past this middle it is again concave forwards. Its external 
end makes a strong anterior sweep towards the periphery. On the periphery 
it is strongly convex forwards. The anterior rib does not form a tubercle, 
although it is prominent on the umbilical edge. It is not in touch with any 
other rib. That portion of the posterior rib, which is actually rib, starts at or 
near the middle of the flank; the first rib behind this begins at the posterior 
edge of the groove, about midway between the middle of the flank and the 
umbilical edge. The second rib behind it starts on the anterior surface of a 
tubercle, which stands on the edge of the groove. There are four of these 
constrictions on the last whorl. The course of the other ribs is very regular. 
They have all got a stretched S -shape, their inner half being very slightly 
convex and their outer half concave forwards. As far as they are visible on 
the periphery they are convex forwards. The spaces . between the ribs are 
broader than the ribs and on the middle of the flank only slightly broader than 
the nearest sulcus in this region. 
The lobe-line resembles most that of Holcodiscus karapadensis and H. 
buddhaicus. The external saddle and both lateral saddles are symmetrically 
divided by a secondary lobe. The external saddle is slender and longer than 
the others. The first lateral lobe is trifid and longer than the ventral lobe. The 
second lateral saddle does not touch the umbilical margin. The first auxiliary 
