134^ SPATITA 



Anodonta I'ignonana Musgr.we, Phot. Conch., 1863. pi. i^ 



fig. I. 

 Anodon lignonanus Rkkve, Conch. Icon., X\'II, 1870, pL 



xxix, fig. 116. 

 Margaron (Unic) ingnonana Lea, Syn., 1870, p. 32. 

 Margaron (Margaritana) vignouana Lea, Syn., 1870, p. 67. 

 SpatJia vignoni Germain, Arch. Zool. Exp. et Gen., (5), I, 



1909, p. 57. 

 f Anodonta rugifcra Dunker, Alal., Bl., A', 1858, p. 225. 



This remarkal)le form, of which several specimens are before 

 me, seems to have most of the characters of the genus Spatha, 

 hinge, muscle scars, etc. In typical Spatha there is only a 

 single dorsal scar in each valve, in this species there may be 

 one or two, while Moncetia may have three. A. rugifera Dun- 

 ker probably equals 5*. vignoniana Bernardi, but there is only 

 a Latin description. Both were published the same year. 



Spatha corkugata Dautzenberg. 



Shell rather solid, convex, oblong, subrhomboid, inequilat- 

 eral ; beaks low : dorsal outline almost regularly curved from 

 the anterior to the posterior end of the shell ; anterior end 

 somewhat narrowed, rounded, subangulate above ; base line 

 very lightly curved; posterior ridge low, somewhat double, 

 ending in a wide biangulation at and .below the median line ; 

 surface slightly corrugated over the earlier growth, striate on 

 the later growth ; epidermis blackish-chestnut ; nacre whitish 

 at the border, greenish within ; hinge thick, edentulous ; dor- 

 sal scars apparently two in each valve ; anterior scars as in 

 .9. xngnoniana. 



I^ength 70, height 42, diam. 24 mm. 



River Niari, West Africa. 

 Spatha corrngata Dautzenbekc. Jl. de Conch.. XLL 1893, P- 



50, pi. viiT, fig. 5. — Simpson, v^yn., 1900, p. 902. 



Quite different in form from 6\ vignoniana, but it has a 

 sculptured surface, and apparently, from the figure, two dor- 

 sal scars in each valve. The wide posterior l)iangulation. and 

 the evenly, rounded dorsal outline will at once distinguish it 



