110 Bulletin American Museum of Natural History [Vol. LIII 
Fluv. Miss. Revoil,’ p. 53, Pl. 1v, figs. 77-78. Limnea poiriert BOURGUIGNAT, 1881, 
‘Moll. Terr. Fluv. Pays Gomaline p. 12; 1882, ‘Moll. Terr. Fluv. Miss. Revoil, 
p. 55, Pl. rv, figs. 79-80. Limnexa revolt Bigune cnet 1881, ‘Moll. Terr. Fluv. Pays 
ce p. 14; 1882, ‘Moll. Terr. Fluv. Miss. Revoil,’ p. 56, Pl. rv, figs. 81-82. 
Lagoon of Tahew Somaliland (type locality of perrieri, poiriert, and revoilt). 
Lymnza (Radix) natalensis undussume (E. v. Martens). See p. 111. 
Lymnzxa (Radix) nimoulensis (A. 'T. de Rochebrune and Germain) = Limnea 
nimoulensis A. T. DE RocHEBRUNE AND GERMAIN, 1904, Bull. Mus. Hist. Nat. Paris, 
p. 141; 1904, Mém. Soc. Zool. France, XVII, p. 8, Pl. 1, fig. 1. White Nile at Nimule, 
Uganda. 
Lymnxa (Radix) nyanse (E. v. Martens) =Limnexa nyanse EH. v. MARTENS, 
1892, Sitz. Ber. Ges. Naturf. Fr. Berlin, p. 16; 1897, ‘Deutsch Ost Afr., IV, Beschalte 
Weichth.,’ p. 134, Pl. v1, figs. 3, 4, and 6. Western shore of Lake Victoria, near 
Bukoba and Towalio. 
Lymnzxa (Radix) tchadiensis (Germain) =Limnzxa tchadiensis GERMAIN, 1905, 
Bull. Mus. Hist. Nat. Paris, p. 484; 1908, in A. Chevalier, ‘L’ Afrique Centrale 
Frangaise,’ p. 493, Pl. v, fig. 3. Southeastern part of Lake Chad. 
Lymnzxa (Radix) vignoni (Germain) =Limnzxa vignoni GERMAIN, 1909, Bull. 
Mus. Hist. Nat. Paris, p. 474; 1911, ‘Doc. Scientif. Miss. Tilho,’ II, p. 178, Pl. 1, 
figs. 8-10. Lake Chad. 
Lymnxa (Radix) vignont var. minor (Germain) =Limnxa vignont var. minor 
GERMAIN, 1911, ‘Doc. Scientif. Miss. Tilho,’ IT, p. 179, Pl. 1, fig. 16. Lake Chad. 
Lymnea (Radix) natalensis (Krauss) 
Plate XI, Figure 3 
Limnxus natalensis Krauss, 1848, ‘Siidafrik. Mollusk.,’ p. 85, Pl. v, fig. 15 
(type locality: Natal). 
Limnea natalensis Krauss. E. A. Smiru, Proc. Zo6l. Soc. London, 1881, p. 295; 
1906, op. cit., I, p. 184; 1904, Proc. Malacol. Soc. London, VI, 2, p. 98; 1909, 
Trans. Zool. Soc. London, XIX, 1, p. 47. 
Mt. Ruwenzori: (Woosnam Coll.). Lake Tanganyika: swamp near Mbete, 
at the southern end of the lake (W. A. Cunnington Coll.). 
Lymnexa natalensis (Krauss) is typically a South African form having 
strongly convex whorls and generally about 15 mm. long. A specimen 
from Port Elizabeth is figured, Pl. XI, fig.3. It is said to range north- 
ward into Rhodesia or farther. North of its typical area, from Angola to 
Kast Africa, the shells generally are larger, about 20 mm. long, though 
small ones also occur. Many names have been given to these snails, 
based on variations in the length of spire and degree of amplitude of the 
last whorl and aperture. Few examples of nomenclature so futile and 
inane can be found, since the variations are far less marked than in any 
good series of L. stagnalis or auricularia. 
The prior name for the large, tropical African Lymnza appears to 
be. L. caillaud: Bourguignat. We are using the name L. n. undussumx 
