NO. 1205. SYNOPSIS OF TRE NAIADES— SIMPSON. 883 



tDIPLODON CUPRINUS Simpson. 

 ""Unio fragilis Sowekby,' Coucb. Icon., XVI, 1856, pi. xxx, fig. 155. 



Island of Chiloe, Chile. 



DIPLODON AUREUS Simpson. 

 " Unio auratus Kuster, Conch. Cab. Unio,1856, p. 161, pi. xlvi, tig. S.^ 



Chile. 



DIPLODON CORIACEUS Dunker. 



^JJnio coriaceus Dunker, Zeits. fiir. Mai., V, 1848, j). 181. — * von Iheking, Arch, 

 fiir Nat., 1893, p. 115. 



Eio Negro, Province of Rio Janeiro, Brazil. 



DIPLODON CHILDRENI Gray. 



* Unio cMldreni Gray, Griff. Cuv., XII, 1831, p. 600 (index), pi. xx, fig. 1.—* Cat- 



low and Reeve, Conch. Icon., 1845, p. 57. — * H. and A. Adams, Gen. Eec. 



Moll., II, 1857, p. 493.—* PyETEL, Conch. Sam., Ill, 1890, p. 148. 

 Margarita (Unio) oMldreni Lea, Syn., 1836, p. 25; 1838, p. 19. 

 *Margaron (Unio) cMldreni Lea, Syn., 1852, p. 28; 1870, p. 44. 



South America. 



(Group of Diplodon hnrrougJiianus.) 



Shell elliptical, moderately solid, inflated, shar^^ly pointed behind, 

 with a high, well- developed posterior ridge; beaks rather full; the 

 sculpture consisting of regularly radiating, widely separated, sharp 

 ridges, the intervening grooves rounded out; ( pidermis smooth, dark 

 olive with lighter bands ; pseudocardinals compressed, rough, vertically 

 ridged, usually trifld or quadrifid in each valve; laterals curved, com- 

 pressed, muscle scars smooth; nacre white, silvery. 



Animal unknown. 



t DIPLODON BURROUGHIANUS Lea. 



* Unio hurrougUianus, Lea, Tr. Am. Phil. Soc, V, 1834, p. 67, pi. x, fig. 27; * Obs., 



1, 1834, p. 179, pi. X, fig. 27.—* d'Orbigny, Guer. Mag., 1835, p. 34.—* Hanley, 

 Test. Moll.,'1842, p. 197 ," * Biv. Shells, 1843, p.l97, pi. xxii, fig. 2.—* d'Orbigny, 

 Voy. Am. Mer., 1843, p. 609. — * Catlow and Eeeve, Conch. Nom., 1845, p. 56. — 

 * H. and A. Adams, Gen. Eec. Moll., II, 1857, p. 493.—* Sowerby, Conch. Icon., 

 XVI, 1866, pi. XXXII, fig. 169.—* P.etel, Conch. Sam., Ill, 1890, p. 146. 



* Margarita ( Unio) iurroughianus, Lea, Syn., 1836, p. 29 ; 1838, p. 21. 



* Margaron ( Unio) hurrotighianiis, Lea, Syn., 1852, p. 31; 1870, p. 50. 



Parana Eiver, South America. 



1 Sowerby's name being preoccupied in Unio, I change it to cuprinus, which has 

 not been used in Diplodon. The date, 1856 on the plate, is perhaps a typographical 

 error for 1866. 



"The name awratos is preoccuiiied in Unio, by Philippi in the Conchylien. This 

 being a different species, I change it to aureus. 



