new Molluscafrom South Africa. 639 



whorled, canaliculate at the sutures, the upper disk rounded, 

 the lower planate, deeply excavate ; the lamellar segments 

 clearly perceived radiating round the umbilicus ; the shell is 

 obtuse-angled at the periphery ; the mouth is obliquely 

 obtuse-triangular, lip simple. 



Four specimens. 



We have taken the largest specimen as the type. 



Assiminea tyttha *, sp. n. (PI. XVII. fig. 11.) 



A. testa minuta, cornea, fere laevi, globoso-conica, solidiuscula ; 

 anfractibus quatuor, apicali obtuse, caeteris ventricosis, longitu- 

 dinaliter indistincte striatulis, ultimo rapide accrescente, caeteris 

 conjunctim magnitudine superante ; apertura subrotunda ; peri- 

 stomate rotundo, siraplici ; columella obliqua, crassiuscula ; oper- 

 culo rubro, littoriniformi, normali. 



Long. 1-50, lat. 1 mm. 



Bab. Howick, near Pietermaritzburg, "on the under 

 surface of the leaves of a sage-like shrub " (Mr. Burnup). 



A few specimens of a very small Assimirtea, bearing some 

 likeness to A. litorina, Delle Chiaje, a native of British and 

 South -European shores. The shell is bright horny, almost 

 smooth, being indistinctly longitudinally striate, rather solid, 

 four- whorled, the apical whorl obtuse, the rest tumid, the 

 last whorl much larger than all the rest together; mouth 

 almost round, outer lip round, simple ; columella oblique, 

 thickened ; operculum normal. 



* TVT06s, small. 



EXPLANATION OF PLATE XVII. 



Fig. 1. Ennea Cairnsi. 



Fig. 2. Burnupi. 



Fig. 3. Pupa (Faula) pereximia. 

 Fig. 4. Hapalus catarractce. 

 Fig. 5. Trachycystis teretiuscula. 

 Fig. 6. Achatina Livingstonei. 



Fig. 7. drakensbergensis. 



Fig. 8. Buliminus (Pachnodus) carinifer. 

 Fig. 9. Subulina tugelensis. 

 Fig. 10. Planorbis (Segmentind) planodiscus. 

 Fig. 11. Assiminea tyttha. 



