NODULARIA 1029 
Umio lacoimi resembles both Unio (Nodularia) @gyptiaca 
Cailliaud, from which it differs by its more elliptical shape, 
much longer cardinals, etc., and Unio (Nodularia) faidherbei 
Jousseaume, from which it is distinguished by its less convex 
shape, more anterior beaks, etc.” 
Var. chudeawi Germain. 
“Shell irregularly elongate-elliptic, very globosely inflated, 
most so in the umbonal region; dorsal margin a little convex 
and slightly oblique; ventral margin irregularly convex; an- 
terior region short, somewhat rounded, cut away towards the 
ventral margin; posterior region a little more than twice as 
long as the anterior, terminating in a tapering point, somewhat 
elevated; beaks very large, very prominent, tuberculate; dor- 
sal edge blunt; the cardinal tooth in the left valve is very 
stout, erect and cleft under the beak, and the two laterals are 
long and unequal; anterior muscular impressions very deep, 
posterior well marked, pallial line superficial. 
Shell thick, slightly cretaceous, solid, with very heavy, very 
irregular, elevated and very unequal strie; large wrinkled 
tubercles on the beaks; nacre very iridescent, slightly tinged 
with salmon. 
Length 42, height 26.5, diam. 26 mm.” (Germain). 
Type locality, N’Guigmi, Lake Tchad. 
Unio (Nodularia) lacowmi var. chudeaut GERMAIN, Bull. Mus. 
Hist. Nat., 1909, p. 541. 
“This very beautiful shell, which I refer as a variety to Unio 
lacoini Germain, is distinquished especially by its somewhat 
cuneiform appearance, its very prominent beaks and its pecu- 
liarly inflated form.” 
NopuLARIA NGUIGMIENSIS Germain. 
“Shell small, rounded-oval, very slightly subpentagonal, 
moderately compressed; valves gaping at both ends; dorsal 
margin straight, ventral margin very convex; antero-dorsal 
and postero-dorsal angles subacute; anterior end rounded, 
slightly cut away towards the base; posterior end one and 
