NO. 1205. SYNOPSIS OF THE NAIADES SIMPSOX. 887 



tDIPLODON DISCULUG Lea. 



1 'itio diacitlus, LEA, Pr. Ac. X. Sci. Phila., IV, 1860, p. 91 ; * Jl. Ac. X. Sci. Phila., 



V, 1863, p. 385, pi. XLIV, fig. 293; * Obs., X, 1803, p. 21, pi. XLIV, fig. 293. 

 * Margaron Unio <liscuhis'LK\, Syu., 1870, p. 55. 



Uruguay River, South America. 



tDIPLODON FUNEBRALIS Lea. 



* Unio funebralis LEA, Pr. Ac. N. Sci. Phila., IV, 1860, p. 91 ; * Jl. Ac. X. Sci. Phila., 



V, 1863, p. 378, pi. XLI, fig. 286; *Obs., X, 1863, p. 14, pi. XLI, fig. 286. 

 *SOWERBY, Conch. Icon., XVI, 1867, pi. LVII, fig. 290. "P^ETEL, Conch. 

 Sam., Ill, 1890, p. 153. 



* Margaron Unio fit ncbralis LKA, Syn., 1870, p. 55. 



Uruguay River. 



tDIPLODON PARANENSIS Lea. 



* Uttio paratunsw LEA, Tr. Am. Phil. Soc., V, 1834, p. 49, pi. xiv, fig. 42. * Obs., I, 



1834, p. 211, pi. xiv, fig. 42. *HANLEY, Test. Moll., 1842, p. 202; *Biv. 

 Shells, 1843, p. 202, pi. xxi, iig. 3. * D'ORBIGXY, Voy. Am. Mer., 1843, p. 

 603. *CATLOW and REEVE, Conch. Xom., 1845, p. 62. * H. and A. ADAMS, 

 den. Eec. Moll., II, 1857, p. 492. *KUSTER, Conch. Cab., 1861, p. 253, pi. 

 LXXXV, fig. 3. * SOWERIJY, Conch. Icon., XVI, 1866, pi. LI, fig. 268; * P^ETEL, 

 Conch. Sam., Ill, 1890, p. 162. 



* Margarita ( Unio) paranmsis LEA, Syu., 1836, p. 33; 1838, p. 23. 

 *^iargaron ( Unio) paranensis LEA, Syn., 1852, p. 34; 1870, p. 55. 



*t Unio nocturntts LEA, Pr. Ac. X. Sci. Phila., IV, 1860, p. 91; * Jl. Ac. X. Sci. 

 Phila., V, 1863, p." 380, pi. XLII, fig. 288; * Obs., X, 1863, p. 16,pl.XLii, fig. 288. 

 * Margaron ( Unio) nocturnus LEA, Syn., 1870, p. 56. 



Uruguay and Parana rivers. 



Section BTJLIOIDEUS Simpson, 1900. 

 (Type, T'nio bulloides Lea.) 



Shell rounded, inflated, thin, nearly equilateral, truncate behind and 

 slightly so before, with a rather sharp posterior ridge and a dorsal 

 wing ; beaks full, rather high, regularly radial ; epidermis smooth, 

 bronzy olive; pseud ocardinals compressed, much elongated, disposed 

 to be split into denticles, two in the right valve and one in the left; 

 laterals two in the left valve and one in the right; dorsal scars few and 

 scattered in the rather shallow cavities; nacre bluish. 



tDIPLODON BULLOIDES Lea. 



* Unio bulloides LEA, Pr. Ac. X. Sci. Phila., Ill, 1859, p. 187; * Jl. Ac. X. Sci. Phila., 



IV, 1860, p. 264, pi. XLII, fig. 144; * Obs., VII, 1860, p. 82, pi. LXII, fig. 144. 

 *KUSTER, Conch. Cab. Unio, 1861, p. 186, pi. LIX, fig. 2. *SOWERBY, Conch. 

 Icon., XVI, 1868, pi. LXXX vin, fig. 275. *P.ETEL, Conch.Sam.,III,1890, p. 146. 

 Margaron ( Unio) "bulloides LEA, Syn., 1870, p. 55. 



Rio de la Plata. 



tDIPLODON SOLISIANUS d'Orbigny. 



* Unio solisiana D'ORBIGNY, Guer. Mag., 1835, p. 35; * Voy. Am. Mer., 1843, p. 604, 



pi. LXIX, figs. 1-3. * SOWERKY, Conch. Icon., XVI, 1868, pi. xcui, fig. 508. 



Rio de la Plata and its affluents. 



