848 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxii. 



tPARREYSIA NYASSAENSIS Lea. 



* Unio nyassaensis Lea, Pr. Ac. N. Sci. Phila., VIII, 1864, p. 108; * JI. Ac. N. Sci. 



Phila., VI, 1866, p. 33, pi. xii, fig. 32; ^ Obs., XI, 1867, p. 37, pi. xii, fig. 32.— 



* Smith, Pr. Zool. Soc. Lond., 1881, p. 298, pi. xxxiv, fig. 34.— *P^tel, Couch. 

 Sam., Ill, 1890, p. 161.— *Ancey, Bull. Soc. Zool. Fr., VII, 1894, p. 225.— 



* VON Martens, Besch. Deuts. Ost-Af., 1897, p. 230. 

 * Margaron (UrAo) nyassaensis Lea, Syn., 1870, p. 30. 



* Unio nyassw Sowerby, Conch. Icon., XVI, 1868, pL xli, figs. 224, 224rt, 2246. 



* Unio nyassanus Bourguignat, Bull. Soc. Mai. Fr., VI, 1889, p. 38. 



* Unio liprmosus 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 hirUi Lea, Pr. Ac. N. Sci. Phila., VIII, 1864, p. 108; " Jl. Ac. N. Sci. Phila., ^ 



VI, 1866, p. 32, pi. XII, fig. 30 ; * Obs., XI, 1867, p. 36, pi. xii, fig. 30.—* Bour- 

 guignat, Bull. Soc. Mai. Fr., VI, 1889, p. 38.— ''Ancey, Bull. Soc. Zool. Fr. 



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



* Margaron ( Unio) Mrkii Lea, Syn., 1870, p. 30. 



Lake Nyassa. 



PARREYSIA UJIJIENSIS Bourguignat. 



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



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



Lake Tanganyika. 



tPARREYSIA AFERULA Lea. 



* Unio afenda Lea, Pr. Ac. N. Sci. Phila., VIII, 1864, p. 109. 



* Unio aferulus Lea, Jl. Ac. N. Sci. Phila., VI, 1866, p. 34, pi. xiii, fig. 34; *Obs., 



XI, 1867, p. 38, pi. XIII, fig. 34.—* Bourguignat, Bull. Soc. Mai. Fr., VI, 1889, 

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



* Margaron {Unio) aferulus Lea, Syn., 1870, p. 30. 



Lake ISTyassa. 



PARREYSIA MONCETI Bourguignat. 



"^ Unio monceti Bourguignat, Moll. Ny. Ouk., 1883, p. 15, figs. 13-15. — *a'ON 

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



Lake Victoria, Nyanza. 



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

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

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

 blend together, but the types are so distinct that I do not feel justified in uniting 

 them even as varieties one of another. 



"There is some confusion about this shell. The form on pi, xxxiv, which Smith 

 probably refers to in the test as fig. 34& 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 iig. 346 on the plate. His 34a, which Smith calls var. tanganyicensis, is 

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

 his name, although he speaks of the var. tanganyicensis Smith. These must not be 

 confounded with the original Unio tanganyicensis of Smith, which is a very different 

 thin."-. . 



