454 Bulletin American Museum of Natural History (Vol. LITI 
also the snails Cleopatra broecki from the Aruwimi, and several fresh- 
water limpets (Ancylide) from the Katanga, Burnupia caffra (Krauss) 
and B. transvaalensis (Craven). 
During “very: low water collectors often enough will find encamp- 
ments of the natives close to the best sites, for at that period the rapids 
or falls offer favorable places also for fishing on a more extensive scale 
than at other times and the colonies of Htherva furnish a most welcome 
staple food. In the northeastern Belgian Congo the large banks of 
Etheria along the Dungu River are regularly exploited by the riverine 
Bakongo and Mangbetu tribes. The younger men are expert divers and, 
with speciallv made iron chisels or spikes, pry loose from the rocks great 
lumps of Hitheria. When the shells are heaped close to the fire the 
adductor muscles relax. Women and children remove the mollusks 
from their shells, spike dozens of them on wooden skewers, and dry 
them as rapidly as possible. They are laid upon wooden racks where the 
combined action of fire, smoke, and sun quickly transforms them into 
heavy brownish flakes which in dry condition can be’preserved for sev- 
eral months, like native dried fish and meat. Decay previous to or co- 
incident with such preparation, far from being objectionable to the 
native taste, rather adds flavor. For consumption these dried mollusks 
are soaked in water until softened and after being thoroughly boiled are 
served as a highly seasoned oyster stew with palm oil and vegetables. 
Though apparently never eaten raw, in certain places in the Uele the 
riverine population prepare the fresh mollusks much like fish, either fried 
or boiled. Hardly any white men along the Uele, the Aruwimi, or the 
Congo in the neighborhood of Stanleyville seemed to be interested in 
these oysters as food. Some of them assured Chapin and myself that 
they were rather bitter. Dybowski,! however, in speaking of his stop at 
Bangi during his trip along the Ubangi River, mentions that when cooked 
these mollusks are rather good eating. The water must have been very 
low, for the Banziri, like other natives living near such favorable rapids, 
collected then their annual harvest of river oysters. 
“With the years, small hills of empty shells accumulate about such 
native camps. On account of the relative scarcity of limestone in all 
these regions such shell heaps always attracted the attention of those who 
at the early period of Belgian occupation were in search of a proper 
substitute. These Hiheria shells indeed furnished an excellent quality 
of lime for the mortar needed to erect brick houses in the different settle- 
ments and also for whitewashing the walls. This was also advantageous 
ie 11893, ‘Route du Tchad,’ p. 366 (Etheria tubifera). 
