Reference List of South African Non-marine Mollusca. 145 
270. TRACHYCYSTIS RIVULARIS (Krauss). 
1848 Helix rivularis, Krs., Siidafr. Moll. p. 77. pl. 4, £. 25. D.F. 
ie nf » Pfr., Zeitschr. f, Malak. v. p. 114. D. 
1853 53 » » Montiiehin. p. 110; dD: 
1874 35 » dick., Fauna N.-O.-Afr. Doo. CN. 
1887 Helix (Pella) rivularis, Krs., Tryon, Man. of Conch. iii. ple, 
pl. 20, f. 85-87. D.F. 
Type in Stockholm Museum. 
Hab. Navan. Source of Mooi River (Wahlberg). 
var. DENSESTRIATA, nov. [S.A.M.] 
Shell small, rather depressed, umbilicate, thin, bright fulvo-cor- 
neous, covered on both sides with close, prominent, regular, curved, 
990909 9 
Oo 9 9 
2 @ @ @ 
a2 ae 
3 2 al 
x 34. 
. Trachycystis rivularis, Krs. (Type). 
var. densestriata, Zwart Kop. 
* Be Pietersburg. 
ordinaria, M. & P., Bloemfontein. 
lirate var., Rustfontein. 
1 
2. iS »” 
3. ” 
4 
5 9) bed ” 
transverse strie. Whorls 44, rounded, gradually increasing. Suture 
impressed. Aperture lunate, descending a little in front; peristome 
thin, simple; columella weak, concave, margin slightly reflexed, but 
in no way covering the umbilicus, which, though not wide, is deep, 
extending to the apex. 
