72 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



between tlie forms as originally described, and it appears impossible 

 to retain eximin as even a varietal name, unless, indeed, it be allowed 

 to stand for the smaller shells with a single tooth on the outer lip 

 and little appearance of a basal swelling. 



The group is now, therefore, reduced to three species, which may 

 be distinguished as follows : — 



Gulella crassilabris (Crvn.) ( == euscJiemon, M. & P.) : One parietal 

 lamella ; one tooth on outer lip ; a slight swelling, sometimes 

 obsolete, at the base. 



Gulella sihasana, Conn. : One parietal lamella ; one tooth, some- 

 times bifid, on outer lip ; one basal tubercle of varying development. 



Gulella distmcta (M. & P.) ( = eximia, M. & P.) : One parietal 

 lamella ; one sinular denticle ; one tooth, sometimes bifid with 

 cusps more or less widely separated, on outer lip ; one basal swelling 

 or tubercle of greatly varying development. 



In addition to the difierence in dentition set forth above, in 

 G. sihasana the basal tubercle is situate slightly more to the left, or 

 higher up on the columellar lip, and the rima is rather more open 

 than in either crassilabris or distincta ; the geographical distribution, 

 moreover, tends to confirm the conchological grouping, distincta 

 (cum eximia) being known, so far, from Middelburg and Barberton 

 in the east ; crassilabris (cum euschemon) from Belfast, Pruizen, 

 Pietpotgietersrust, and Lydenburg in the north centre, and sibasana 

 from the extreme north of the Transvaal. 



It may be noticed that in this revision there is no mention of 

 G. infans (Crvn.) or its numerous allies. The explanation is that 

 they are not represented in Junod's collection, and that, although 

 infans is an almost perfect miniature of crassilabris, its group seems 

 to be entirely distinct and need not enter into the foregoing 

 calculations. 



Genus Kerkophorus, Godwin-Austen. 

 Kerkophorus perfragilis, sp. no v. PI. II, Figs. da-c. 



Shell subnautiloid, flattened, imperforate, extremely thin, glossy, 

 transparent, pale olivaceous-corneous ; in the Type there is a very 

 faint, narrow, pale rufous band just above the periphery, but this 

 is absent in the generality of specimens. Spire almost flat ; apex 

 submammillate. Whorls 3^, rapidly increasing, the first micro- 

 scopically rather sparsely punctate, remainder covered with very 

 faint, somewhat irregular transverse stria), corresponding with the 

 lines of growth. Suture shallow. Aperture elongate-ovoid ; 

 peristome simple, acute, projecting far more above than at the base ; 

 columella weak, concave, margin not sufficiently reflexed to form 

 a rima. 



Diam. maj. 15-5 ; min. 12-3 ; alt. 7'8 ; apert. alt. 7-5 ; long. 

 8-9 mm. 



Hab. — Shilwane district. 



