894 I'Rix i:i:i>i\t;s or mi: \ATIO\AL MUSI-CM. 



tDIPLODON MUTABILIS Lea. 



* 1'niu mntdbilix LEA, Pr. Ac. X. Sci. Phila., Ill, 1859, p. 152; *J1. Ac. N. Sci. Pliila., 



IV, 18(50, p. 248, pi. xxx vii, tig. 127; *Obs., VII, I860, p. 66, pi. xxxvin, fig. 

 127. * P/KTKL, Couch. Sam., Ill, 1890, p. 160. 

 ' Manjaron ( (~ni<>) mut<ibili>i LKA, Syn., 1870, p. 53. 



Murray River, Australia. 



Subgenns La:VIKOSTEIS Simpson, 1900. 

 (Type, Unio stagnorum Dautzenberg.) 



Shell irregularly quadrate, thin, inequilateral, compressed, rounded 

 and narrowed in front, somewhat biangulate and truncate behind; 

 beaks rather lo\v, without sculpture; 1 surface finely concentrically 

 grooved; epidermis delicately lamellated and serrate; pseudocardinals 

 small; laterals elongated; anterior muscle impressions small, well 

 marked; posterior scars superficial; nacre bluish white. 



Animal unknown. 



DIPLODON STAGNORUM Dautzenberg. 



* Unio stagnorum DAUTZKXBKRG, Bull. Acad. Belg., XX, 1890, p. 372, pi. i, figs. 7, 10. 



Kongo River, Africa. 



The following are unfigured and uncertain species. 



* E7>ito depressa D'ORBIGNY, Guer. Mag., 1835, p. 34. 2 



* Unio fokkeai DINKEK, Zeits. fiir Mai., IX, 1853, p. 54. 



Rio de la Plata, Brazil. According to von Ihering, this= U. tchcat- 

 lei/anus Lea. 



* Unio koscretzi CLESSIN, Mai. BL, X, p. 172. 

 River Guahyba, Brazil. 



* Unio macropterus BUNKER, Zeits. fur Mai., Ill, 1846, p. 109. 

 Brazil. 



*~Unio paraguanus VON MARTENS, S. B. Ges. Nat. Fr., 1895, p. 



* Unio zealandicus P.KTKL, C. Sam., Ill, 1890, p. 172. Said to be of Gray. Where? 

 Unio damnoica D'ORBIGNY. Where? 



Cnio yua1njba> VON IHERING. 

 Unio d'tlnopiformls VON IHERING. 

 Unio bishoffi VON IHERING. 

 Unio tcbaslana' VON I BERING. 

 Unio ilieriiigi VON CLESSIN. 



1 According to Dantzenberg the beaks of the remarkable species on which I have 

 founded the above snbgenns are completely smooth. It has the appearance of a 

 Diplodon in all other respects, according to the figures and description. Dautzen- 

 berg does not very carefully describe the teeth. 



2 According to d'Orbigny (Voy. Am. Mer.,p. 611), this species, which he says is the 

 depressa of Lamarck, is found in Chile, near Valparaiso. It can not be Lamarck's 

 species. 



