NODULARIA 1019 
Section CaLarura Conrad, 1853. 
Celatura Conran, Pr. Acad. Nat. Sci. Phila., 1853, p. 267. 
Shell elliptical, pointed or rounded behind, usually slightly 
produced at the post-base; beak sculpture consisting of zig- 
zag ridges, which are generally quite pustulous, the sculpture 
often extending on to the usually rayed disk ; teeth compressed ; 
pseudocardinals lamellar. 
Animal described under Nodularia. 
Type, Unio egyptiacus Cailliaud. 
Group of Nodularia egyptiaca. 
Characters the same as of the section. 
NoDULARIA AGYPTIACA (Cailliaud). 
Shell irregularly elliptical, subinflated, usually rather thin, 
subinequilateral ; beaks moderately high and full, their sculp- 
ture consisting of subnodulous, zigzag ridges, sometimes of 
sharp or elevated pustules; dorsal line curved; anterior end 
narrowed and rounded; basal outline curved, fuller behind the 
middle; dorsal slope obliquely truncated; posterior ridge 
rounded, ending in a blunt point about on the median line; 
surface with irregular growth lines; epidermis generally 
smooth, with slight wrinkles on the dorsal slope, yellowish- 
green, banded, with faint, green rays, usually ashy on the 
umbonal region, somewhat shining; teeth lamellar; pseudo- 
cardinals one in the left valve and two in the right ; laterals two 
in the left valve and one in the right; muscle scars shallow ; 
nacre bluish. 
Length 42, height 29, diam. 19 mm. 
Nile system; Upper Cazamance, West Africa (Vignon) ; 
both sides of the equator in Central Africa (Dohrn). 
Unie species nuovo, SAvicny, Icon. Moll., Egypt, 1813,’ pl. 
vit, figs. 3-6. 
Unio egyptiaca CAILLIAuD, Voy. a Méroé, II, 1826, pl. Lx1, 
figs. 6, 7. 
Margarita (Unio) egyptiacus Lea, Syn., 1838, p. 21. 
