ON SOUTH AFRICAN ENNE^. 



37 



labral plait ; and the basal denticle is replaced by an incon- 

 spicuous, scarcely raised, minute ridge like that of var. 

 discrepans. It differs from var. discrepans in being 

 more cylindrical, in the labral process being less massive and 

 more pointed, and in the total absence of the conspicuous 

 denticle on the upper edge of the labral plait. 



Height, 2-95, width, 1"55 mm. 



Hab. — Ntimbankulu, Mid-Illovo (Burnup). Other locali- 

 ties: Karkloof (Taynton), Maritzburg, Howick and Dargle 

 (Burnup) . 



The following dimensions of shells that I have measured 

 will give an indication of the extent of variation in size and 

 proportion that this form is liable to : 



It will be seen from the above table that, while this variety 

 is less stable in ratio of width to height than the variety 

 discrepans, it does not exhibit so much variation in that 

 respect as isipingoensis, typical. It will also be seen that,^ 

 though some individual specimens of the other forms may be 

 smaller than some examples of this, in striking an average of 

 the shells measured, sturanyi is the smallest, and isipin- 

 goensis, typical, the largest. 



The nature and disposition of the armature of the aperture 

 in the several forms remain remarkablv constant, no inter- 



