120 . Bulletin American Museum of Natural History [Vol. LIII 
Planorbis (Coretus) choanomphalus E. v. Martens. GeErmarn, 1916, Bull. 
Mus. Hist. Nat. Paris, p. 196. 
Lake Edward: Vichumbi, living and subfossil (Stuhlmann Coll.; Schubotz Coll.; 
Gromier Coll.). Lake Kivu: (Schubotz Coll.). 
Lake Kivu: near Kisenje (R. Van Saceghem Coll.). 
This shell has much the appearance of the American Planorbis 
bicarinatus Say, type of the subgenus Helisoma, being angular on the 
left side around the deeply sunken spire, while the right side has a narrow 
umbilicus, the whorl narrowly rounded but scarcely angular. ‘The peri- 
phery is broadly rounded. _ , 
Diameter, 11.5 mm.; height, 6 mm. ; 4% whorls. 
a b Cc 
Fig. 5. Planorbis choanomphalus EK. v. Martens. Kisenje, Lake Kivu. «144. 
Planorbis choanomphalus var. basisulcatus E. v. Martens 
Planorbis choanomphalus var. basisulcatus KE. v. Martens, 1897, ‘Deutsch Ost 
Afr., IV, Beschalte Weichth.,’ p. 149, Pl. vi, fig. 16. Grrmarn, 1916, Bull. Mus. 
Hist. Nat. Paris, p. 197. 
Originally described from Kassarosi Island and Bukoba Bay in Lake Victoria, 
and subfossil on the shores of Lake Edward near Vichumbi (Stuhlmann Coll.). 
Planorbis smithi (Preston) 
Text Figure 6 
Biomphalaria smithi Preston, 1910, Ann. Mag. Nat. Hist., (8) VI, p. 535, Pl. 
Ix, figs. 26 and 26a. 
ae ee Edward: (type locality, without more definite information; J. E.8. Moore 
Oll.). 
Lake Edward at Kabare (J. Bequaert Coll.). 
The prominent character of this species is the deviation towards the 
left of the last half-whorl. The left side is bluntly angular. A specimen 
from Kabare measures: diameter, 13 mm.; altitude, 6.5 mm. Another 
from the original lot: diameter, 9.6 mm.; altitude, 5 mm. Both are 
figured. | 
While the unusual shape suggests various planorbid groups of re- 
mote places, such as the Andean Taphius, this species appears to be 
merely a modification of the adowensis type, perhaps to be placed in 
the same section of the genus. 
