CONNOLLY: MOLLUSCA FEOM NORTHERN TRANSVAAL. 73 



Type in my collection. 



A flatter, proportionately more elongate form than K. phcedimus 

 (M. & P.), whicli appears to be its nearest relative among known 

 species of Peltatince. 



Genus Trachygystis, Pilsbry. 

 Trachycystis planti (Pfeifier). 



Hah. — Shilwane district. 



The Natalian shell to which this name has usually been applied 

 of late years is remarkable for the expansion of the peristome in 

 adult examples, a feature peculiar, among South African species of 

 Trachycystis, to itself and to T. calorama, M. & P. There is no 

 mention of such expansion in any early description of the species, 

 nor does it occur in any of the earlier series in the British Museum ; 

 on the other hand, the latter are not as large as more recently 

 collected individuals, and may easily be slightly immature. 



Junod's shells are of rather a rufous shade, while Craven's, in the 

 British Museum, are of paler yellow, but all appear to be conspecific. 

 None are quite adult or show any trace of expanded peristome, and 

 I cannot separate them from the older typical examples of planti 

 from Natal. 



Trachycystis junodi, spec. nov. PL II, Figs. la-c. 



Shell small, subglobose, narrowly rimate, very thin, not very 

 glossy, semitransparent, greenish corneous. Spire just raised 

 sufficiently for each whorl to project above the next ; apex sharp. 

 Whorls 5; rather convex, last very rounded ; rather rapidly 

 increasing, protoconch (first whorl) microscopically punctate, 

 remainder covered above and beneath \\4th close, regular, curved 

 transverse striae, crossed by equally close spiral striae. Suture 

 narrow but well defined. Aperture very slightly flattened lunate ; 

 peristome simple, acute. Columella very weak, margin narrowly 

 reflexed, almost concealing the narrow, but deep, rima. • 



Diam. maj. 8-3 ; min. 7-1 ; alt. 5-5 ; apert. alt. 5 ; lat. 4-2 mm. 



Hah. — Mt. Manotsuri, Shilwane district, 4,000 feet. 



Type in Kimberley Museum. 



A fine new species, with no very close allies. 



Trachycystis shilioancensis, spec. nov. PL II, Figs. 3a-&. 

 Shell small, subconic globose, narrowly umbilicate, very thin, 

 rather dull, semitransparent, pale rufous-corneous. Spire somewhat 

 exserted, sides slightly convex, meeting at an angle of 95°. Whorls 

 5 J, rather flat, last very round ; rather gradually increasing ; 

 protoconch {\\ whorl) microscopically punctate, with very faint 

 transverse striation when nearing the other whorls, which are 

 covered all over with very close, faint, transverse, crossed by finer, 

 equally close, spiral striae. Suture small, but clear. Aperture 

 lunate ; peristome simple, acute. Columella weak, margin narrowly 



VOL. XV. — DECEMBER, 1922. 6 



