1927} Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo 343 
Typical specimens of C. radiata from the White Nile are figured 
(Fig. 72a-d). They are costulate, the ribs giving place to fine strie toward 
the dorsal margins. A rapidly widening violet ray runs downward from 
the beaks, and another, generally brownish one is on the posterior 
slope. The beaks are small and the hinge is narrow. 
The name of this species must be changed on account of the prior 
Cyrena radiata Hanley (1844, Proc. Zool. Soc. London, p. 159); but 
the needed rectification will require a thorough study of African Corbi- 
cule for which we have not sufficient material. 
Figs. 73 Figs. 74 
Fig. 73. a-b, Corbicula radiata edwardi Pilsbry and Bequaert. Type. X2, 
Fig. 74. a-b, Corbicula tanganyicensis Crosse. X2. 
Corbicula radiata edwardi, new subspecies 
Text Figure 73a-b 
Lake Edward at Kabare (J. Bequaert Coll.). 
The surface is nearly smooth, with only a few narrow concentric riblets on the 
anterior part, not extending upon the anterior-dorsal slope, and generally there are 
some irregular radial wrinkles on the posterior slope. The very large, finely striate 
lunule is defined by a weak raised line. Valves covered with an ecru-olive epidermis, 
fading to white at the beaks, which are marked with a median and a posterior violace- 
ous ray, as in typical radiata. Some examples are marked with narrow darker rays. 
The hinge-plate and teeth are narrow, as in radiata. The interior is deep violaceous, 
varying in shade, often with a light or white zone below; teeth dark or light. 
Length, 11.5 mm.; height, 10.0 mm.; diameter, 8.0mm. Type. 
“ 13.3 mm.; largest example. 
This form, heh was taken in some abundance, differs from typical 
C. radiata by its nearly smooth surface. It is more oval than C. tan- 
ganyicensis, with lower beaks and a narrower hinge. | 
Corbicula tanganyicensis Crosse 
Text Figure 74a-b 
se 
Corbicula radiata var. tanganyicensis Cross, 1881, Journ. de Conchyl., XXIX, p. 
290 (based upon C. radiata var. E. A. Smith, from Tanganyika). 
Cyrena (Corbicula) radiata var. E. A. Smrra, 1881, Proc. Zool. Soc. London, p. 295. 
