Anthores leuconotus Pasc., indigenous in East, South-East, South and South-West Africa, is an important ring-barking and wood-boring pest of the main stem and root of arabica coffee. The duration of the life-cycle ranges from 12 to 25 months, with most individuals requiring 16–20 months. Thus beetles developed from eggs laid during the long rains (April–June) of one year will mostly emerge during the short rains (Nov.–Jan.) of the following year, with some appearing during the rains preceding and others during the ensuing rains.If the mean life-cycle is taken to be 18 months, the approximate duration of each stage is as follows:— eggs require 21–23 days for eclosion; larvae in the first five instars ring-bark the tree for 4 months, and those in the final two instars bore into the wood for 12 months; the pupal period lasts about 4½ weeks, and the beetle remains in the tree for a further two weeks before emerging.

Analysis of the results obtained from suction-trap catches of the coffee leaf-miners, Leucoptera meyricki Ghesq. and L. caffeina Wshbn. on an unsprayed block of coffee at the Coffee Eesearch Station, Lyamungu, on the slopes of Kilimanjaro, are given.By thermal summation methods it was possible to delimit successive generations of moths with some degree of accuracy and the generation catches were used for regression analysis with various meteorological factors. With L. meyricki, a negative correlation was shown between the rate of increase from one generation to the next and with both maximum and mean daily temperature, solar radiation and duration of sunshine taken as means over the period of each generation. In each case, the highest degree of correlation was found between the meteorological data in one generation and the rate of increase in the next.When the generation catches were plotted on a logarithmic scale it was found that linear regression lines could be fitted to the periods of both rise and fall of the annual outbreak. With L. meyricki, the rate of increase of the rise was negatively correlated with, and the rate of decrease of the fall positively correlated with, the size of the generation present at the beginning of the outbreak. It is therefore possible, knowing the size of the minimum generation, to predict the size of the coming outbreak. No such relationship could be proved with L. caffeina, probably because the catches of the key generations were very small, but when the catches of the two species were pooled the same relationship held. It is probable that parasites are the main factor governing the annual fluctuations.

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