214 Transactions of the Royal Society of South Africa. 



Family CYRENIDAE. 



Genus Corbicula von Mtihlfeld, 1811, 



Corhicula africana (Krs.), 1848. 



1846. Cyrena radiata Parr., Phil., Abb. u. Beschr. ii, p. 78, pi. 11, 4, 

 fig. 8. D.F. 



1848. Cyrena africana, var. olivacea Krs. {—gauritziana Krs. in litt. and 

 radiata Parr.) Krs., Siidafr. Moll, p. 8, pi. 1, fig. 8. D.F. 



Hab. L. Marques. Tette (Peters) ; Itschongove (Schenck) ; R. 

 Zambesi {radiata, Brancksik) ; Gorongozo District (Wells Cole) ; Zangwe 

 Basin (Cressy). 



The name radiata cannot be retained for this species, as it was first 

 described as a Cyrena, and is therefore preoccupied by Cyrena radiata, 

 Hanley (P.Z.S. 1844, p. 159). However, a new name is unnecessary, since 

 Krauss bestowed on it in 1848 that of C. africana var. olivacea. At the 

 same time, he stated that this variety was the typical form of the species, 

 so that the varietal name is not required and africana can stand alone. 

 The beautiful little shells with radiate umbones often occur in company 

 with those of duller hue, and appear to be quite inseparable from them 

 except as a colour variety. 



Corbicula astartina (Mts.), 1860. 



1860. Cyrena astartina Mts., Mai. Blatt. vi, p. 219, pi. 3, figs. 6-7. 

 D.F. 



Hab. L. Marques. Tette (Peters). 



Easily distinguishable from any of the africana group by its more 

 elongate form. 



Corbicula kirki Prime, 1864. 



1864. Corbicula kirkii Prime, Ann Lye. Nat. Hist. N.Y. viii, pp. 66, 67, 

 fig. 12. D.F. 



Hab. Mozambique (Kirk). 



In most kindly forwarding me the beautiful photograph, from which the 

 subjoined text-figure has been reproduced, of the type of this species in the 

 United States National Museum, Dr Paul Bartsch remarks : " The type is 

 pale horn coloured on the outside, with the umbones flushed with purple ; 

 the interior is very pale purplish, deepening toward the umbones. Another 

 specimen . . . is of much darker colour ; in fact, the interior is dark purple." 



