96 TRUNCATELLINA OF SOUTH AFRICA. 



convex, closely lirate transversely excepting the first 2 l / 2 , 

 which are smooth, the last whorl compressed round the um- 

 bilical region, and flattened near the middle of the labium 

 [outer lip]. Aperture straight, subangularly rounded, about 

 1/4 the height of the shell, peristome reflexed, widely so at 

 the columellar margin, slightly thickened, pale, untoothed, 

 with labium [outer lip] somewhat incurved about the middle. 

 Columella straight. 



"Alt. 2.17, lat. 0.92 mm. (maj.). 



"Alt. 2.10, lat. 0.88 mm. (min.) (Burnup). 



"A slender cylindrical form which seems to be quite dis- 

 tinct from all described species, though seemingly comparable 

 with P. quantula M. & P., which is less tapering upwards, 

 broader in comparison to its length, and fine in sculpture, 

 and also with P. pentheri Stur., a more conical shell, with 

 smoother sculpture, the whorls particularly ventricose, and 

 shallower sutures" (Burnup). 



The original type (from Pretoria) is slightly smaller in 

 dimensions than those given above, and is not in very perfect 

 condition (Melv. & Pons.). 



Transvaal: Pretoria, type loc. (Farquhar, McBean) ; Hei- 

 delberg (Miss Livingston) ; Standers Kop (Connolly). Zulu- 

 land: Dukuduku Forest (Toppin). 



Pupa iota MELV. & PONS., Ann. Mag. N. H., (6), xiv, 1894, 

 p. 93, pi. 1, f. 10; BURNUP in M. & P., (8), i, 1908, p. 77, pi. 

 1, f. 11, with var. livingsto-ncc Burnup, p. 77, pi. 1, f. 12. 

 BURNUP, Ann. Mag. (8), vii, 1911, p. 406, with var. living- 

 stoncc, p. 407. Jaminia iota and var. livingston<c CONNOLLY, 

 Ann. S. Afr. Mus., ix, 1912, p. 182. 



The ribbing is decidedly stronger than in T. sykesi, but it 

 varies a good deal, from moderately close to more spaced, in 

 both the typical form and mut. livingstoncc. The size also is 

 quite variable in single lots, the largest individuals, it appears, 

 being the toothed mutation. 



There is a well-developed columellar lamella, oblong and 

 vertical, dorsal in position, in the typical iota, as well as in 

 livingstoncc, but in the former not so large. 



The type of iota was said to measure 1.25 x .5 mm., with 7 



