1927] Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo 193 
nut-brown bands variously arranged, and either few or many. In some 
old examples these are almost lost in a general darkening of the whorl. 
The aperture is broadly oval, wide in the upper part. The columella 
is long, whitish, thin. Adnate portion of the inner lip is quite short 
Length, 31.0 mm.; diameter, 28.5 mm.; aperture, 19.0X15.0 mm. Zambi. 
i 2a * 28 .0 = 19.5X15.5 ‘ 
a o 29.0 . 19.0X 1520 i 
Fo 0 Seaea 30.5 a 21.0X17.0 Malela. 
The operculum has a large, very distinctly defined scar, irregularly 
and rather strongly roughened with traces of concentric wrinkles near 
the nucleus. Color very dark brown, the scar and border black. It 
measured 19.0 14.0 mm. in a shell of 30.5 mm. diameter. . 
L. nsendweensis is a more depressed shell, with the spire less broad- 
ened, the umbilicus wider in large shells, and the subsutural flattening 
is more pronounced; it is also more solid. | 
Ampullaria subcarinata Sowerby, was described from the Congo, 
believed to have been collected by Cranch on the Tuckey Expedition; 
if so, it was taken in the Congo mouth region where L. zntortus is found. 
It is therefore probably, as von Martens thought, a form of this species; 
yet the shorter spire and larger aperture shown in the figures of both 
Sowerby and Swainson cast a little doubt on this identification. 
“At Zambi, Malela, and Banana Lanistes intortus was found always 
near the shore of the river on the edges.of sandbanks, frequently where, 
due to the shallowness of the water, there are muddy, alge-covered 
sites.” (H. L.). : 
Lanistes bicarinatus Germain 
Plate XVIII, Figure 1 
Lanistes bicarinatus GERMAIN, 1907, Bull. Mus. Hist. Nat. Paris, p. 428, fig. 27 
(type locality: in the Congo River at Brazzaville). 
Leopoldville (J. Bequaert Coll.). 
Germain has given a good account of this handsome species, but 
from a small, probably quite immature example of 25 mm. diameter. 
A fine specimen from Leopoldville shows the adult form. There is 
a strong carina at the shoulder, which almost disappears before reaching 
the lip. Above it the surface slopes up to the suture. The second or 
peripheral angle is well developed on the face of the last whorl, but dis- 
appears on its last half.e A strong angle bounds the deep, well-like 
umbilicus. The glossy surface shows very slight traces of fine spiral 
strie in places. The color is brownish-olive above, chamois beneath, 
with chestnut-brown bands. 
