smith : molltjsca of lake tanganyika. 101 



Unto. 



Altogether, including the genus Grandidieria, which does not 

 seem to be separable from Unio, forty-three species of this genus 

 have been named. That many of these are mere synonyms there 

 is very little doubt, but without more material to work with it 

 seems hopeless to attempt to discuss them, many being known 

 by description only. The names are : U. Niloticus, Cailliaud ; 

 U. Gerrardi, Bohni, rostralis (= rostrata, Bgt.), Martens (pp. 223, 

 238) ; Burtoni, "Woodward ; Tang any iceiisis, Thomsoni, Horei, Smith ; 

 Servainiana, Smithi, cyrenopsis, gravida, corhicxda, insignis, rhyyichonella, 

 Bourguignati, eaUista. granulosa, sinyularis, Anceyi, incarnata, Giraiidi, 

 elongata, cyrenopsis, Locardiana, mira, rotundaia, Hauttecoeuri, Ujijensis, 

 Charhonnieri, Coulhoisi, Dromauxi, Randaheli, Visseri, Vtnckei, Moineti, 

 Menardi, Larigerianus, Jouherti, Josseti, Bridouxi, Guillemeti, calathus, 

 all of Bourguignat. (i, ii ; Bull. Soc. mal. France, 1885, vol. ii, 

 pp. 1-12; JN'ouveautes MalacoL, 1886, pp. 7-23; Especes nouv. et 

 genres nouv. Oukerewe et Tanganika, 1885, pp. 15-25.) 



MuTELA EXOTICA (Lamarck). 



Iridina exotica, Lamarck: Anim. sans Vert., 2nd ed., vol. vi, p. 571 ; 



Reeve's Conch. Icon., fig. 2. 

 /. elongata, Sowerby : Genera, fig. 1 ; Conch. Icon., fig. 1. 

 /. Nilotica, Sowerby: Zool. Journ., vol. v, pi. ii ; Conch. Icon., fig. 4 ; 



Kiister, Conch. Cab., pi. xxv, fig. 3. 

 Mutela exotica. Smith: Proc, i, p. 350; ii, p. 296; Crosse, p. 131. 



First collected in the lake by Mr. E. Coode Hore. M. soleniformis, 

 Bourg., may be the same as this species. Other fonns described from 

 the lake are : Bridouxi, Jouherti, Vysseri, Moineti, Monceti, Lavi- 

 geriana, Bourguignat (ii, and Nouveautes MalacoL, 1886, pp. 25-31). 

 Only four of M. Bourguignat's species have been figured, and these 

 look as if they are mere variations of the same form. 



Beazz^a. 



Brazzcea, Bourguignat : iv, pp. 32, 38 ; v, p. 44; ii, p. 61, pi. xxviii, 

 figs. 1-6, pi. xxix, figs. 1-5 ; Martens, p. 258. 

 Of this genus thirteen so-called species have been described, and 

 judging from the figures of six of them there appears to be very little 

 to distinguish them. The names are : B. Anceyi, ventrosa, Randaheli, 

 Newcomhiana, Moineti, Lnvigeriana, Jouherti, eximia, elongata, Coulhoisi, 

 Charhomiieri , Bridouxi, Bourguignati. (Bourguignat, ii, and Nouveautes 

 MalacoL, 1886, pp. 45-59.) 



MONCETIA. 



Moncetia, Bourguignat : iv, pp. 34, 38 ; ii, p. 65, pi. xxx, figs. 1-8 ; 

 Martens, p. 258. 

 There seems little, if anything, to separate this genus from Spatha. 

 It appears to be represented by a single variable species, which has 

 been separated by M. Bourguignat under the names M. Anceyi, 

 Jouherti, Bridouxi, Lavigeriana, Moineti, and Rochehruniana. 



