ANODONTITES 1 447 



away at the base ; posterior region two and one-half times as 

 long- as the anterior, very slightly narrowed, snbtruncate ; beaks 

 eroded, showing a lead-colored, very iridescent nacre, rounded, 

 slightly compressed and quite prominent ; dorsal ridge narrow 

 towards the beaks, becoming obsolete towards the posterior 

 region; ligament brilliant deep chestnut-color, quite strong. 

 14 mm. long; hinge very slightly curved, scarcely thickened; 

 anterior muscular impressions subelliptical, quite deep; pos- 

 terior very faint ; pallial almost none. Shell thick, solid, com- 

 paratively heavy, with quite fine, concentric stride; epidermis 

 a brilliant chestnut^brown, becoming rusty posteriorly ; nacre 

 greenish-blue, very iridescent. 



Length 44-45, height 27-26, at the beaks 16-15, diam. 17.25- 

 17 mm." ( Germain). 



Type locality, Ecuador. 

 Anodonta (Glaharis) hidalgoi Grrmain, Bull. Mus. Hist. Nat., 



i(p8, p. 64. 



Anodontttf.s DUi.cis (von Ihering). 



"vShell elongate, oval, of medium size, gaping considerably 

 at both ends, not very thin, quite inflated, with a shining sur- 

 face. Anterior end rounded, narrower than the posterior end, 

 which is broader and regularly rounded with the inconspicu- 

 ous point above the middle. Beaks quite inflated, broad, ap- 

 proximate, and much eroded. The vertical profile is elongate 

 heart-shaped. The horizontal profile shows the greatest diam- 

 eter at about the middle of the length, from which point it 

 evenly diminishes towards the posterior end, whereas anterior- 

 ly it very slowly decreases as far as the beaks, beyond which 

 it rapidly slopes to the anterior region. The rounded anterior 

 margin forms a distinct angle with the dorsal margin and 

 curves regularly into the evenly rounded ventral margin. The 

 dorsal margin is straight in front, slightly curved behind and 

 passes gradually into the posterior margin. The dorsal area 

 is broad, low, slightly abrupt; the lunule is linear and very 

 small. The ligament is long, ending in a triangular sinulus. 

 the anterior edge of which is the shorter and almost vertical 



