ANODONTITES I403 



Genus ANODONTITES Brugiiire, 1792. 

 Anodontites Brug(jif,re, Journ. Hist. Nat. Paris, I, 1792, p. 



Patularia Swmnson, Malacology, 1840, pp. 287, 381. 

 Glabaris Gray, Proc. Zool. Soc. Lond., 1847, P- ^97- — Simp- 

 son, Syn., 1900, p. 916. 



Shell rounded to elongated, iutlated, subsolid ; beaks full, 

 smooth ; epidermis smooth or cloth-like, rarely having faint 

 rays ; hinge line straight or slightly curved, edentulous, some- 

 times a little sinuous, the escutcheon distinct and large; nacre 

 soft tinted, the prismatic border wide and well defined. 



Animal with the marsupium occupying the whole of the in- 

 ner branchiae, which are united their entire length to the ab- 

 dominal sac ; palpi generally semicircular or kidney-shaped ; 

 attached along their entire upper length, not projecting pos- 

 teriorly ; branchial and anal openings with or without papillae, 

 not united into siphons in the specimens examined, separated 

 by a strong bridge ; superanal opening not closed below. 

 Type, Anodontites crispatus P)rug. 



Section Anodontites s. s. 

 Shell rounded to elliptical ; posterior ridge low or wanting. 



Group of .tnodontitc's patagonicus. 



Shell solid, inflated, obovate, usually somewhat produced 

 behind the center of the base ; beaks quite full, projecting above 

 the hinge line ; epidermis olive-brown, rather smooth, gener- 

 ally rayless ; anterior muscle scars well defined. 



Animal with the gills large, rounded below ; palpi rather 

 large; mantle thickened at edge, and furnished with palpi in 

 front of the branchial opening; branchial opening large, with 

 numerous minute papilLie ; anal opening large, with no papilhe. 



Anodontitl;s patagonicus (Lamarck). 



Shell quite variable in form, usually somewhat obovate, con- 

 vex to subinflated, solid, inequilateral ; beaks moderately full 

 and high : dorsal line lightly arched : anterior end more or less 



