284. | Bulletin American Museum of Natural History [Vol. LIII 
liricincta (Smith), this species differs by the broad form, shouldered 
whorls and the ample aperture with a very heavy callus of the inner 
lip near the posterior angle. 
Fig. 49. Anklet worn by children of the Medje tribe, composed of Potadoma 
medjeorum, P. ignobilis, teleostean vertebree and humerus of Varanus niloticus. 
¥% natural size. 
Potadoma ponthiervillensis (Dupuis and Putzeys) 
Plate XXV, Figures 1-If 
Melania ponthiervillensis DuPUIS AND Purzrys, 1900, Ann. Soc. Malacol. Belg- 
ique, XX XV, Bull. Séances, p. xv, fig. 23. 
Lualaba River at Ponthierville (type locality; Dupuis Coll.). 
Stanleyville near the Falls of the Congo River; 105 specimens (H. 
Lang and J. Bequaert Coll.). 
This beautiful melanian has been well described and figured by 
Dupuis, but further illustrations are now given to show its variation. 
The form varies from ovate to elongate, the color from chestnut- 
brown to sayal-brown. On the well-rounded last whorl there are four 
strong, knotted spiral cords, the knots or tubercles often with a short 
scale; below these there is a fifth smaller spiral cord, and sometimes a 
sixth around the columella. Under the lens is seen a fine sculpture of 
