1372 BRAZZ.lvA 



1)r.\zza:.\ .\nci':yi I'.ourguignat. 



Shell irregularly elliptical or subrhomboid, inflated, slightly 

 ineqiiivalve, somevvhat inequilateral, thin ; beaks not raised 

 above the dorsal line, flattened ; dorsal line straight, winged a 

 little in front and behind ; anterior end rounded, ang'led above ; 

 base line curved, fullest behind the middle ; posterior ridge 

 faintly double, curved downward in the middle, ending in a 

 biangulation at and below the median line ; dorsal slope ob- 

 liquely truncate ; surface concentrically striate ; splendid violet 

 wine color, shining, with blackish violet margins ; interior col- 

 ored as the exterior; left valve projecting over the right in a 

 somewhat sinuous wing. 



Length 66, height 47, diam. 36 mm. 



Lake Tanganyika. 

 Brazzcca anceyi Hourguicnat, Esp. Ouk. et Tan., 1885, p. 33; 



Icon., 1888, pi. xxviii, figs. 1-4. — Simpson, Syn., 1900, p. 



907. 

 Bra:;:zea anceyi Germain, Arch. Zool. Exp. et Gen., (5), I, 



1909, pp. 52, 57. 

 Brasscea exiniia Bourguignat, Un. aiul Ir. Tan., 1886. p. 57; 



Icon., 1888, pi. XXIX, fig. 5. 



This must be a magnificent shell according to the descrip- 

 tion of its author. 



Germain, (1. c), refers all of Bourguignat's species to this 

 as synonyms. 



Brazz.T'A r.ouRGUiGNA'i'i Rourguiguat. 



Shell irregularly subrhomboid, slightly inequivalve and in- 

 equilateral, subsolid. greatly inflated ; beaks somewhat ele- 

 vated, elongated and much swollen ; dorsal outline straight, 

 ending in a low wing behind ; anterior end irregularly round- 

 ed, subangulate above, cut away below ; base straight but full 

 behind the middle ; posterior ridge double, ending in a biangu- 

 lation at and below the median line ; dorsal slope obliquely 

 truncate ; surface concentrically striate, opake blackish-violet, 

 lighter at the beaks ; valves brilliant ; nacre violet-wine-color, 

 splendidly iridescent. 



Length 60, height 32, diam. 36 mm. 



Lake Tan^anvika. 



