576 Bulletin American Museum of Natural History [Vol. LIII 
Planorbis gibbons Spherium nyanze 
Ree stanleyi (? =adowensis) Corbicula radiata 
et sudanicus tanganikanus eae pusilla 
*Pila stuhlmanni *Parreysia bakerz 
Viviparus rubicundus fi i acuminata 
*Bulamus walleri Celatura xegyptiaca 
Fi alberta *Mutela emini 
Melanoides tuberculata eS OU, 
*Cleopatra pirothr 
A number of other species have been reported at various times 
from the lake, but we believe that most of them were misidentified: 
— Planorbis adowensis, P. apertus, Pila wernet, Spherium stuhlmanni, 
“Unio” cailliaudi, “Unio” teretiusculus, and Mutela nilotica. Potadoma 
liricincta was originally described as from Lake Albert, but most probably 
the type specimens were obtained in some of the streams flowing to the 
Itur1. 
Although about half of the species of the above list are not known 
from outside Lake Albert, the fauna shows nothing quite striking, being 
frankly Nilotic in its general make-up. Even the peculiar Mutela emini 
is undoubtedly a close relative of the more widely distributed M. nilotica. 
It should, however, be remembered that what we know at present of the 
fauna is based entirely upon shells picked up at the shore. The deep 
waters of the lake are totally unexplored. 
Lake Edward 
Lake Edward (Ruite Ngize or Ngezi, formerly known as Lake Albert 
Edward) is situated south of the equator, at an altitude of 940 m.,in one 
of the widest portions of the Albertine Rift. It stretches from north to 
south over some 80 kilometers, while its width, from east to west, reaches 
50 kilometers in the northern half, but is considerably less in the south. 
Its total area has been calculated at 2,150 square kilometers. The western 
side rises rapidly to heights of 2,500 m. and more and the shore is quite 
steep, often forming cliffs 300 m. to 900 m. above the level of the water; 
there are, however, many intervening beaches of pebbles and coarse sand, 
usually fringed with thickets of reeds. Elsewhere the shores are generally 
low, more or less swampy, and frequently preceded by a belt of rushes 
(Scirpus) or cattail (Typha). This is especially true of the southeastern 
corner, where the water is shallow and choked with submerged aquatic 
plants and also presents a number of low, almost floating islets of mud and 
decaying vegetation. The lake is generally shallow, although its greatest 
depth has not yet been ascertained. It is only 5 m. deep at the distance 
of a kilometer and a half from the northern shore. It contains no islands 
of any importance. | 
