68 ACHATINA, EAST AFRICA. 



Bourguignat writes as follows : " In this species the flam- 

 mules of the last whorl do not run zigzag to the base, but 

 at the periphery suddenly assume a spirally forward de- 

 scending direction. It is the only Achatina in which I have 

 observed this pattern of nammules. A. arctespirata is re- 

 markable for the spire, which though with a large, obtuse 

 summit is pyramidal-acuminate, the whole having a short, 

 squat appearance. The spiral increase is very slow, the last 

 whorl notably tapering downwards, making it appear more 

 swollen in the middle. 



'This species is very abundant throughout the southern 

 region of Tanganyika, but it is very rarely found in good 

 condition on account of the fires set by the natives, which 

 make the shell a uniform dull white by destruction of the 

 epidermis. ' ' 



This species may prove to belong to the South African 

 group Cochlitoma. 



62. A. SPEKEI Dohrn. 



Shell oblong, rather solid, very obsoletely granulate above, 

 whitish under a corneous epidermis, irregularly streaked 

 with fulvous. Spire conic, the apex rather obtuse, suture 

 submarginate. Whorls 6 to 7, a little convex, the last three- 

 sevenths the total length. Columella obliquely truncate, arcuate, 

 covered with a thin callous. Aperture oblong-ovate (Dohrn). 



Lake Victoria Nyanza (Speke). 



A. spekei DOHRN, Proc. Zool. Soc. Lond., 1864, p. 117. 

 PFR., Monogr., vi, 220. 



Differs from A. ustulata Lam., according to Dohrn, by 

 the more slender spire, slimmer at the apex, the more convex 

 early whorls and more arcuate columella. No dimensions have 

 been given. It must resemble Pfeiffer's var. fc of A. allin. 



63. A. STUHLMANNI Martens. PL 34, fig. 13. 



Long-fusiform, thin, Avith unequal wrinkle-striae and on 

 tlic upper whorls with spiral strise, which entirely disappear 

 on the last whorl. Greenish-brown, with a few blackish 

 si leaks. Suture oblique, crenate, without margining line. 



