1927} Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo BOD 
EKupera differs from Sphxrium by the decidedly inequilateral shell 
and the reduced cardinal teeth, not more than one in each valve, and 
having the simple shape of a tubercle lengthened in the direction of the 
hinge. 
The following African species have been described. 
Eupera bequaerti Dautzenberg and Germain. See p. 358. 
Eupera ferruginea (Krauss) =Cyclas ferruginea Krauss, 1848, ‘Siidafrik. Mol- 
lusk.,’ p. 7, Pl. x1, fig. 7. Knysna River, Cape Colony. 
Eupera letourneuxi BourGuiGNatT, 1883, Ann. Sc. Nat. Zool., (6) XV, p. 134. 
Canals of Alexandria, Egypt. 
Eupera mediafricana Pilsbry and Bequaert. See below. 
Eupera mediafricana etheriarum Pilsbry and Bequaert. See p. 357. 
Eupera parasitica (Deshayes)= Pisum parasiticum ‘Parreyss’” DESHAYES, 
1854, ‘Cat. Conchif. Brit. Mus.,’ II, p. 280 (Upper Nile). Limosina ferruginea 
“Krauss” JIcKELI, 1874, Nova Acta Ac. Nat. Cur. Dresden, XXXVII, 1, p. 
293, Pl. x1, figs. 16 and 17. Eupera jickelii Bourcutgnat, 1888, Ann. Sci. 
Nat. Zool., (6) XV, p. 184, based upon Jickeli’s Pl. x1, fig. 17; cf. Germain (1908, in 
A. Chevalier, ‘L’ Afrique Centrale Frangaise,’ p. 585), who states that this is only a 
variation of E. parasitica. Limosina parasitica (Deshayes) EK. A. Smirx, 1892, Ann. 
Mag. Nat. Hist., (6) X, p. 126. First Cataract at Assuan, Upper Nile (Parreyss): 
Lake Victoria (Bishop Haaninetbn. 
Eupera sturanyi (L. Waagen). See p. 358. 
Eupera mediafricana, new species 
Text Figures 79a-f and 80a _ 
Tshopo River near Stanleyville, in cavities of the shells of Etheria 
(Lang and Chapin, and J. Bequaert Coll.). | 
Shell relatively higher than EH. parasitica, more inflated than FE. parasitica or E. 
ferruginea. The subtrapezoidal shell is light brownish olive, rather profusely marked 
with black spots. The weakly, very finely striate surface has many cuticular lamine. 
In the right valve there is no cardinal tooth; a rather strong ridge runs posteriorly, as 
far as the anterior end of the posterior laterals, which are short and double, the lower 
one stout, the upper one very slender. The anterior lower tooth is short and robust, 
the upper slender and much reduced. In the left valve there is a small, oblong 
cardinal, and the lateral teeth are rather slender. . 
Length, 5.30 mm.; height, 3.70 mm.; diameter, 2.90 mm. 
66 4.80 3.30 . a 2.60 
nee he a and 
. 4.75 ee i 3.10 
ABD) Sy BAG nt eae 
rt 4.30 gn Hea | a 2.70 
4 4.10 area te 8 ma 2.30 
We have found the proportions of height to length highly variable 
in the series from Stanleyville, as may be seen by the measurements 
given above. 
