I4IO ANOnONTTTES 



Anodon ruhicnndns Sowerby, Conch. Icon.. XVII. 1870, pi. 



XXX, fig-. 118. 

 Margaron (Anodonta) nibicunda Lea, Syn.. 1870. p. 75. 

 Glabaris rribicundtis Simpson, Syn., 1900, p. 918. 



The type of this species has the epidermis considerably 

 eroded. It is a shorter shell than pa::ii, not so solid nor richly 

 colored, the posterior end is widely and almost squarely trun- 

 cate, meeting the dorsal line nearly at a right angle, while in 

 pazii it is slopingly subtruncate or slightly rounded. In the 

 type the nacre at the border shows colored bands. 



Anodontites rotund'js (Spix). 



Shell almost orbicular, a little narrower in front, subsolid, 

 inequilateral, subinfiated ; beaks elevated and full, turned in 

 over a long, narrow, clean lunule ; posterior end sometimes 

 slightly truncate, often almost evenly rounded ; hinge line 

 curved ; surface almost smooth ; epidermis finely and delicately, 

 concentrically wrinkled, olive, greenish-brown or yellowish- 

 brown, often feebly rayed and having two or three broad, 

 darker rays on the dorsal slope ; nacre bluish, silvery, having 

 a narrow, outer, iridescent border, and delicately, radially stri- 

 ate throughout ; prismatic border wide, lurid. 



Length 75, height 64, diam. 38 mm. 



Brazil. 

 Anodon rotund us Spix, Test. Fluv. Bras., 1827, p. 28. pi. xx, 



figs. 2-4. 

 Anodon rotunda Kuster, Conch. Cab. Ano.. 1853. p. 33, pi. 



VIII, fig. I. 

 Margaron f Anodonta) rotunda Lea, Syn., 1870. p. 81. 

 Glabaris rotunda von Iherinc, Arch, fur Nat., 1893, p. 59. 

 Glabaris rotundus Simpson, Syn., 1900, p. 918. 

 Anodonta cailliaudii Lea, Pr. Ac. N. Sci. Phila., IV, i860, p. 



308 ; Jl. Ac. N. Sci. Phila.. V, 1863, p. 395. pi. xl,v, fig. 297 ; 



Obs., X. 1863, p. 31, pi. XLV. fig. 297. — Ceessin, Conch. 



Cab. Ano.. 1873. p. 105. pi. xxxn, figs. 3, 4. 

 Anodon cailliaudi Sowerby, Conch. Icon., XVII, 1867, pi. xii, 



fig. .38. 

 Margaron f Anodonta) cailliaudii Lea, Syn.. 1870. p. 81. 



