1897.] NATURAL SCIENCES OF PHILADELPHIA. 357 



NEW ACHATINID.E AND HELICIDiE FROM SOMALILAND. 

 BY HENRY A. PILSBRY. 



The following descriptions are based upon material collected by 

 Dr. A. Donaldson Smith. Other mollusks presented to the Acad- 

 emy of Natural Sciences of Philadelphia by the same intreped ex- 

 plorer belong to species already known. They represent so small a 

 fragment of the fauna of this interesting part of Africa that their 

 enumeration here may be dispensed with. 



Achatina chrysoleuca n. sp. 



Shell ovate, with conic spire, in general contour like A. variegata. 

 Solid and strong, though not very thick. White, with a thin golden- 

 brown cuticle, which is deciduous over the greater part of the shell, 

 remaining behind the aperture and in the depressions between longi- 

 tudinal plications elsewhere; later 1=] whorls immaculate, the next 

 earlier with spaced, somewhat zig-zag and rather broad brown 

 streaks, the next earlier narrowly streaked, the streaks straight. 

 Whorls of the spire soiled white. Whorls 62 (the apical whorls 

 truncated, perhaps 1 or I2 whorls being thereby lost), mod- 

 erately convex, the last quite convex. Surface shining, finely de- 

 cussated on the spire, the sculpture hardly visible to the naked eye, 

 and gradually becoming obsolete, the spirals lost on the latter 1£ 

 whorls, which are somewhat coarsely plicatulate. Sutures even 

 above, weakly and irregularly serrate below. Aperture a little ex- 

 ceeding half the length of the shell, pure white within, subvertical, 

 acuminate above, deeply excised by the body-wall ; outer lip rather 

 regularly arcuate, but less curved above, simple ; columella short, 

 cylindric, very deeply concave on the front and the side toward 

 aperture, abruptly truncated at base, delicate flesh-tinted ; parietal 

 wall with a thin, transparent varnish. Alt. 105, diam. 58 mm. 

 Longest axis of aperture 60, greatest width of cavity 33 mm. 



Tulu Didirko, in about lat. 4° 4' N., Ion. 39° 36' E., at 3,580 ft. 

 alt. (Dr. A. Donaldson Smith, March 27, 1895). 



Type is No. 68,113, coll. A. N. S. P. It is an ivory-white shell, 

 with some inconspicuous marking on the spire. The cuticle is 

 largely deciduous. Nothing very nearly allied seems to be de- 

 scribed from this portion of the continent. 

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