212 Bulletin American Museum of Natural History [Vol. LITT 
Type locality: on the western shore of Lake Tanganyika between Pambete and 
Kibanga. 
According to Bechen, this is the form of the southern region of the Lake. 
In Stappers’ collection it is represented by specimens from the bay of Sumbu; bay 
of the Luvu; and off the Kalembwe. 
Neothauma tanganyicense var. euryomphalum (Bourguignat) 
Neothauma euryomphalum BourGuienatT, 1888, ‘Iconogr. Malacol. Tanganika, 
Pl. u, figs. 7 and 8; 1890, Ann. Se. Nat. Zool., (7) X, p. 35, Pl. 11, figs. 7 and 8. GER- 
MAIN, 1905, Bull. Mus. Hist. Nat. Paris, p. 258; 1908, ‘Rés. Scientif. Voy. Afrique 
Foa,’ p. 660. 3 
Neothauma jouberti BourGuIGNAT, 1888, ‘Iconogr. Malacol. Tanganika,’ PI. 
i, figs. 4 and 5; 1890, Ann. Sc. Nat. Zool., (7) X, p. 34, Pl. 111, figs.4 and5. KosBeEtr,. 
1907, in Martini and Chemnitz, ‘Syst. Conch. Cab., n. F., II, 21a, Paludina,’ p. 160, 
PE text hea 
Neothauma vysseri BouRGUIGNAT, 1888, ‘Iconogr. Malacol. Tanganika,’ Pl. 111, 
fig.6; 1890, Ann. Se. Nat. Zool., (7) X, p. 37, Pl. 111, fig. 6. 
Lake Tanganyika: beach of Kibanga (type locality); beach of the peninsula. 
Ubuari; mouth of the Luandazi River. All these on the western shore. 
According to Germain, this is the form of the northern region of the Lake. Stap- 
pers obtained it off Toa and in the pond of Gongwe near Toa. 
Neothauma tanganyicense var. major Germain 
Neothauma euryomphalum var. major GERMAIN, 1905, Bull. Mus. Hist. Nat. Paris, 
p. 258; 1908, ‘Rés. Scientif. Voy. Afrique Fo,’ p. 660, figs. 14 and 15. 
Type localitv: northern region of Lake Tanganyika. 
Amnicolide 
(HyYDROBIIDH, PALUDESTRINID of authors) 
The shell is small or minute, usually ovate-conic, but varying from turreted to. 
depressed and umbilicate, covered with a thin, translucent or olivaceous periostra- 
cui; aperture ovate or rounded. Operculum spiral or with a spiral nucleus, corneous. 
or with a calcareous layer. 
Tentacles slender, with the eyes sessile at theirexternal bases. Male organ long, 
inserted on the back some distance behind the tentacles; its form characteristic for 
the several genera. Foot truncate and with projecting angles in front, rounded behind; 
in locomotion not extending in front of the rostrum. Radula with 3.1.3 teeth, all 
with denticulate cusps. Central tooth having basal denticles on the face of the 
tooth, the basal margin trilobed. Lateral (or admedian) teeth with trapezoidal body, 
tapering shank and unequal denticles. Marginal teeth with numerous equal’ 
denticles. The insertions of the lateral and marginal teeth are near together and. 
remote from the central tooth. The feces are in the form of small oblong pellets. 
This very large family is found almost all over the world, 
temperate and tropical latitudes. It is but poorly represented in Africa 
as now known and is unknown in Madagascar and the Mascarenes. A 
few genera, such as Perzngia, are truly marine; others (Paludestrina and. 
