1056 GRANDIDIKRIA 



2T,a in the P. Z. S. referred to above, save that its beaks are 

 not quite so large as there figured. It seems to be a larger 

 shell and the hinder end is more decidedly drawn into a point, 

 and it is apparently a little solider than biirtoni. By an error 

 Grandidieria anceyi was allowed to stand as a separate species 

 in the Synopsis. I do not know whether it or G. smithi has 

 precedence, both having been published the same year, but I 

 believe that they are the same. 



Grandidieria gravid \ Bourguignat. 



Shell short, irregularly oval, subsolid, inflated, inequilateral ; 

 beaks rather high and pointed, turned forward, with zigzag- 

 radial sculpture ; anterior end rounded, subangulate above ; 

 base very full, especially behind the middle, but incurved in 

 front of the posterior point ; posterior ridge narrowly double, 

 ending behind just below the median line in a narrowly bi- 

 angulate snout or beak ; surface with zigzag-radial and well- 

 marked concentric sculpture; pseudocardinals somewhat elon- 

 gated, compressed, reflexed and cut into strongly marked 

 teeth ; laterals rather ragged ; nacre whitish or purplish. 



Length 33, height 26, diam. 20 mm. 



Lake Tanganyika. 

 Grandidieria gravida Bourguignat, Bull. Soc. Mai. Fr., H, 



1885, p. 7, pi. I, figs. 1-6; Icon. Moll. Tan., 1888, p. 41, pi. 



xviii, figs. 11-16. — Simpson, Syn., 1900, p. 829. 

 Grandidieria rostrata Bourguignat, Bull. Soc. Mai. Fr., 11. 



1885, p. 10, pi. I, figs. 10-12; Icon. Moll. Tan., 1888, p. 41, 



pi. XVIII, figs. 17-19. 

 Unio rostralis von Martens, Besch. Deuts. Ost-Af., 1897, p. 



238. 

 ■ Grandidieria locardiana Bourguignat, Esp. Ouk., 1885, p. 18. 



— Simpson, Syn., 1900, p. 830. — Germain, Moll. Lac Tang., 



1908, p. 682, figs. 31-32. 



vShorter in proportion to length than G. tanganyicensis and 

 liaving more compressed, reflexed pseudocardinals. These, as 

 figured by Bourguignat, are remarkable and resemble to some 

 extent those of Lampsilis pan'a of the United States. 



