848 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL.XXII. 



tPARREYSIA NYASSAENSIS Lea. 



* Unio nijaasaensis LEA, Pr. Ac. X. Sci. Phila., VIII, 1864, p. 108; * Jl. Ac. N. Sci. 



Phila., VI, 1866, p. 33, pi. xn, fig. 32; * Obs., XI, 1867, p. 37, pi. xn, fig. 32. 

 SMITH, Pr. Zool. Soc. Lond., 1881, p. 298, pi. xxxiv, fig. 34. 'P.ETEL, Coucli. 

 Sam., Ill, 1890, p. 161. "ANCEY, Bull. Soc. Zool. Fr., VII, 1894, p. 225. 

 vox MARTENS, Besch. Deuts. Ost-Af., 1897, p. 230. 

 * Margaron (Unio) nyasaaensix LEA, Syn., 1870, p. 30. 



* Unio nyassw SOWERBY, Concli. Icon., XVI, 1868, pi. XLI, figs. 224, 224a, 224&. 

 * .Vnio nyassanus BOURGUIGNAT, Bull. Sof. Mai. Fr., VI, 1889, p. 38. 



* Unio hfi-mo8U8 BOUKGUIGNAT, Bull. Soc. Mai. Fr., VI, 1889, p. 38. *ANCEY, 



Bull. Soc. Zool. Fr., VII, 1894, p. 226.' 



Lake Nyassa, Central Africa. 



tPARREYSIA KIRKII Lea. 



" Unio kirkii LEA, Pr. Ac. N. Sci. Phila., VIII, 1864, p. 108; * Jl. Ac. N. Sci. Phila., 



VI, 1866, p. 32, pi. xn, fig. 30; * Obs., XI, 1867, p. 36, pi. xn, fig. 30. *BouR- 

 . GUIGNAT, Bull. Soc. Mai. Fr.,VI, 1889, p. 38. "AxcEY, Bull. Soc. Zool. Fr. 



VII, 1894, p. 225. * VON MARTENS, Besch. Deuts. Ost-Af., 1897, p. 229. 



* Margaron ( Unio) kirkii LEA, Syn., 1870, p. 30. 



Lake I^yassa. 



PARREYSIA UJIJIENSIS Bourguignat. 



* Unio nyassaensis var., SMITH, Pr. Zool. Soc. Lond., 1881, p. 298, pi. xxxiv, fig. 34. 2 



* Grandidieria ujijiensis BOURGUIGNAT, Bull. Soc. Mai. Fr., II, 1885, p. 7. 



Lake Tanganyika. 



tPARREYSIA AFERULA Lea. 



* Unio aferula LEA, Pr. Ac. N. Sci. Phila., VIII, 1864, p. 109. 



* Unio aferuhis LEA, Jl. Ac. N. Sci. Phila., VI, 1866, p. 34, pi. xin, fig. 34; *Obs , 



XI, 1867, p. 38, pi. xin, fig. 34.* BOURGUIGNAT, Bull. Soc. Mai. Fr., VI, 1889, 

 p. 38. *ANCEY, Bull. Soc. Zool. Fr., VII, 1894, p. 226. 



* Margaron ( Unio) aferttlus LEA, Syn., 1870, p. 30. 



Lake Jfyassa. 



PARREYSIA MONCETI Bourguignat. 



* Unio monceti BOURGTIGNAT, Moll. Ny. Ouk., 1883, p. 15, figs. 13-15. "VON 



MARTENS, Besch. Deuts. Ost-Af., 1897, p. 228. 



Lake Victoria, Nyanza. 



1 E. A. Smith, in Pr. Zool. Soc. Lond., 1877, p. 719; 1893, p. 640, believes that Unio 

 kirki Lea and aferulus Lea are but varieties of Unio nyassaensis, and that Unio hermosus 

 Bourguignat is identical with it. It is possible that the three forms of Lea may 

 blend together, but the types are so distinct that I do uot feel justified in uniting 

 them even as varieties one of another. 



2 There is some confusion about this shell. The form ou pi, xxxiv, which Smith 

 probably refers to in the text as fig. 34fc is simply fig. 34 on the plate, and is, I think, 

 a distinct species, which has received the name of ujijiensis from Bourguignat. 

 There is no fig. 34fc on the plate. His 34a, which Smith calls var. tanganyicensis, is 

 U. nyassaensis Lea. Bourguignat probably alluded to the fig. 34 when he bestowed 

 his name, although ho speaks of the var. tanyanyicensis Smith. These must not be 

 confounded with the original Unio tan;/anyicen8<s of Smith, which is a very different 

 thing. 



