The host range and feeding habits of seven species of Culex mosquitoes at Keneba, the Gambia, are described from precipitin tests of blood-meals and from observations on their attraction to calf, man, duck and pigeon baits. Feeding habits were classed nonspecific, mammalian or ornithophilic. Culex thalassius Theo. was non-specific, bloodmeals being identified from mammals (59·5%), birds (38·1%) and reptiles (2·4%). Large numbers were attracted to calf, man, ducks and pigeons. C. tritaeniorhynchus Giles fed almost exclusively on cattle: 17 of 19 blood-meals were identified as from cow. Many specimens were taken at calf, smaller numbers at man, and the few attracted to ducks fed readily. Birds were the main source of blood for C. decens Theo. (54·8%), C. invidiosus Theo. (87·5%), C. nebulosus Theo./cinereus Theo. (93·3%), C. tigripes Grp. & Charm. (98·3%), C. univittatus Theo. (two out of three) and C. weschei Edw. (one out of one). Reptile feeds were recorded for C. decens (14·3%), C. invidiosus (5·0%), C. nebulosus/cinereus (6·7%) and C. univittatus (one out of three). C. invidiosus and C. univittatus were common only at pigeon bait where some 13% fed on the birds.

The flowers, leaves, young branches and pods of Cola nitida were attacked by Crematogaster buchneri Forel at Gambari Experimental Station, Nigeria. The ants scrape off the epidermis, so that affected leaves fall and pods become shrivelled. In 1970 damage to leaves and branches occurred in 6% and 1% respectively of the Cola trees in a 3·98-ha plot; in 1971 the figures were 7% and 2%. About 3% of the total pods were damaged in 1970, none in 1971. C. buchneri attacked 12 species of wild plants in the Cola plot, but when caged with plants in the laboratory, the ants attacked only Phyllanthus floribundus and C. caricifolia. The ants tend Coccus hesperidum L. and make small greyish-black nests of earth mixed with fine frass in crevices between main veins of leaves, at leaf nodes or terminal buds. Attack on living plant tissues shows a degree of convergence between C. buchneri and Atta spp. and Acromyrmex spp.