262 DORCASIA. 



Alt. 15-16, diam. 22-25 mill. (Mouss., in Journ. Conch. 1887, 

 p. 292.) 



Rehoboth, northern Great-Namaland. 



D. NAMAQUENSIS Melvill & Ponsonby. PI. 28, fig. 1. 



Shell slightly umbilicated, globose, the surface very minutely lon- 

 gitudinally wrinkle-striate, scarcely shining, brownish flesh colored, 

 thin. Whorls 5, the last inflated, rotund, submalleated at the lip ; 

 celumella smooth, whitish. Aperture ovate; peristome reflexed, 

 whitish, the columellar margin callous, subdilated ; umbilicus 

 covered. Alt. 30, diam. 27 mill. (M. & P.) 



Namaqualand, S. Africa. 



Helix (Dorcasia) namaquensis M. & P., Ann. Mag. Nat. Hist. (6), 

 viii, p. 237 (Sept., 1891) ; I. c., 1892, t. 4, f. 12. 



D. PORPHYROSTOMA Melvill & Ponsonby. PI. 28, fig. 3. 



Shell covered umbilicate, 'conic- pyramidal, ample, longitudinally 

 rugose-striate, pale ashy-white, rather solid. Whorls 5, subconvex, 

 the last rounded. Aperture ovate, purple within ; peristome reflexed, 

 purple, the columella smooth. 



Alt. 43, diam. 38 mill. (M. & P.) 



Namaqualand, S. Africa. 



Helix (Dorcasia) porphyrostoma M. & P., Ann. Mag. S". H. (6), 

 viii, p. 238 (Sept., 1891); ix, t. 4, f. 11. 



This very fine species is near the well-^nown H. globulus 

 Mull., from which, however, and all near allies, it differs in the conic- 

 ally pyramidal shape, the whorls being gradually attenuate toward 

 the apex. There is no sign of malleation, so conspicuous a feature 

 in H. globulus and rosacea in all their forms ; and, lastly, the outer 

 lip is more simple, being not so conspicuously reflected, nor is the 

 deposit of purple enamel both on the outer and columellar lips so 

 rich in either substance or color. Two specimens, both precisely 

 similar. There are also unnamed examples in the National Collec- 

 tion. (M. <fcP.) 



D. GYPSINA Melvill & Ponsonby. PI. 28, fig. 2. 



Shell covered umbilicate, globulose-conic, thick, longitudinally 

 rugose-striate, chalky-whitish, little shining. Whorls 5, the last 

 whorl compactly rounded. Aperture depressed-oval, whitish within ; 

 peristome reflexed, white, the columellar margin smooth, white. 



Alt. 24, breadth 20 mill. (M. & P.) 



Springbok, S. Africa. 





