Protasite, a new barium-containing member of the uranyl oxide hydrate group, occurs as bright orange pseudo-hexagonal platelets associated with uraninite and uranophane on unidentified rock matrix from Shinkolobwe mine, Zaïre. Protasite is monoclinic, Pn with a 12.295(2), b 7.221(1), c 6.9558(8) Å, β 90.40(2)°, and V 617.50(11) Å3. The tabular pseudo-hexagonal crystals are flattened on {010}, 0.1 mm to 0.5 mm wide and up to 0.1 mm thick. They are biaxial negative, 2 V = 60–65°, β and γ 1.79–1.83, and X = b. Sector twinning is common. Microprobe analysis shows BaO 15.0, UO3 78.0, H2O(diff.) 7.0%. The structural formula is Ba[(UO2)3O3(OH)2]. 3H2O, Z = 2, and density(calc.) = 5.827(3) g cm−3. Complete crystal-structure analysis shows protasite to be the simplest model structure of the uranyl oxide hydrate group.

L'étude histologique des coupes des rayons osseux des nageoires pectorales de Clarias gariepinus pêchés entre décembre 1985 et février 1986 dans le bassin de la Luki (Zaïre) a montré que ces organes possèdent des marques cycliques pouvant être reconnues et envisagées comme critères d'âge.Ces deux types de marques, probablement synchronisées avec l'alternance saison sèche/saison des pluies, sont bienindividualisées : zone de croissance active (Z) et des lots de lignes d'arrêt de croissance (LAC).

Three severe outbreaks of cassava mealybug (CM), Phenacoccus manihoti, have occurred in Zaire. Two were associated with droughts. The third occurred in the driest part of the country and ended only when nearly all cassava plants had been killed. Native coccinellid predators sometimes greatly reduced CM populations, but only after the cassava crop had been heavily damaged. The exotic coccinellid Diomus sp. may be an effective biological control agent in Kinshasa, where CM on a hybrid form of cassava remained common during the rainy season. CM populations in Kinshasa declined greatly in the second year after the release of the exotic parasitoid Epidinocarsis lopezi. In one study the number of mummies with E. lopezi increased with host densities up to 20 CM per shoot tip. Since CM populations remained low after the releases of E. lopezi it is tentatively concluded that E. lopezi, despite considerable rates of hyperparasitism, prevents CM outbreaks over the whole area of its distribution (130,000 km2) in western Zaire.