The Non-Marine Mollusca of Portuguese East Africa. 137 



Martens. That from Langenburg differs througli having less swollen 

 whorls. All the shells figured are somewhat different from one another ; 

 it appears to me that the material is not extensive enough to decide whether 

 they are varieties, or only local forms, of a single species, or, in part, distinct 

 species. The embryonal sculpture is not always recognisable, since the 

 shells are somewhat weathered, as is the case in that from Bongo ; in some 

 it consists of fine spiral striation." 



It is clear from the foregoing that not much can be done towards the 

 elucidation of this species until further topo-types from Bongo, in better 

 condition, are available for examination. If Cressy's shells are correctly 

 assigned, L. elatior is certainly quite specifically distinct from mozambicensis, 

 having weaker sculpture and nearly always a higher spire. The first 2 

 whorls are rather strongly, closely, microscopically transversely wrinkled 

 and extremely finely, faintly spirally striate ; remainder very closely, finely, 

 faintly, transversely striate, the striae being finer, fainter, and closer 

 than in mozambicensis. 



Subfamily SITALINAE. 



Genus Sitala H. Adams, 1865. 



Sitala diaphana Conn., 1922. 



(Plate IV, fig. 8.) 



1922. Sitala diaphana Conn., A.M.N.H. x, p. 116. D. 

 Hob. L. Marques. District N. of Macequece (Cressy). 



An extremely thin and fragile shell, unlike anything known to me ; 

 the largest example seen measures 4-7 mm. in maximum diameter, but is 

 too much worn to show the spiral sculpture which is characteristic of 

 fresher specimens. 



Genus Kaliella Blanford, 1863. 

 Kaliella barrakporensis (Pfr.), 1852. 



1854. Helix barrakporensis Pfr., Conch. Cab., p. 415, pi. 147 (1853), 

 figs. 20-22. D.F. 



1882. Kaliella sigurensis G.-Aust., L. and F. W. Moll. India, i, p. 5, 

 pi. 1, fig. 11. D.F. 



1912. Kaliella sigurensis G.-Aust., Conn., Ann. S. Afr. Mus. xi, p. 117. N. 



1914. ,, barrakporensis Pfr. {= sigurensis, G.-Aust.), Dautz. and 

 Germ., Kev. Zool. Afr. iv, p. 17. 



Hah. L. Marques. District north of Macequece (Cressy). 



The type of K. sigurensis has not been available for examination, but 

 examples from Pretoria, identified by God win- Austen as that species, 

 20 



