LECANIUM COFFEE, Walker, of the order Hemiptera, the coffee bug of Ceylon, for some years devastated some of the plantations of Ceylon. They are greedily devoured by the large red ant, Formica smaragdina, Fab., and an attempt was made to eradicate the bug by the introduction of the ant, but their attacks on the coolies' bare skins prevented the full success of the experiment. Lecanium coffein establishes itself on the young shoots and buds, which it covers with a noisome incrustation of scales, enclosing its larva), from the pernicious influence' of which the fruit shrivels and drops off. It is al Coccus, and a number of brownish wart-like bodies may be seen studding the young shoots and occasionally the margins on the under side of the leaves. Each of these warts is a transformed female, containing a large number of eggs (700), which aro hatched within it. When the young ones come out of their nest, they may be observed running about on the plant, looking like wood lice ; but shortly after being hatched the males seek the under side of the leaves, while tho females prefer the young shoots as their place of abode. The larvm of the males undergo transformation into pupm beneath their own skins, and their wings are horizontal, and their possession of wings may possibly explain the comparatively rare presence of the male on the bushes. The female retains her powers of locomotion until nearly her full size, and it is about this time that her impregnation takes place. The pest does not produce great injury until it has been two or three years on an estate ; but at length the scales on the plants become numerous, the clusters of berries assume a black, sooty look, and a great number of them fall off before they are mature. The young shoots have a disgusting look, from the number of yellow pustular bodies form ing on them, the leaves get shrivelled, and on many trees not a single berry forms. The coffee bug first appeared in 1843 on the Lupallu Galls estate, and it or a closely allied species has been observed on the Citrus acida, Psidium pomiferum, Myrtus Zeylanica, Rosa Indica, Careya arborea, Vitex negundo, and other plants, and most abundantly on the coffee bushes in moist places. It reappears though eradicated, and is easily conveyed on clothes, and from one place to another. Dr. Gardner, whom Sir J. E. Tennent quotes, is of opinion that all remedies have failed, and that it must wear itself out as other blights do. The male of the brown or scaly bug,
Lecanium coffem, is of a clear, light pinkish brown colour, slightly hairy and very pretty. It is more delicate than the male Pseudococcus. The females when young are yellowish, marked with grey or light brown, and old individuals are light brown with a dark margin. It affects cold, damp, and close localities 3000 feet in height, and the propagation, as in the white bug, is continuous. The brown bug is much infected with parasites, amongst which the most common are eight minute Hymenoptera (wasps), with brilliant colours; but a mite, the Acarus trans lucens, and the larvae of the Chilocorus circum datus, a kind of lady-bird, also feed on the bug. In the larva state, the male and female brown bug are not distinguishable. The number of eggs produced by a female brown bug is about 700. Those of the white bug are not so numerous, but their propagation in Ceylon is continuous throughout the year, and this explains their great abundance compared with cold countries, where the produce is one generation of young annually. The brown bug, particularly the full-grown female, is largely infested with parasites, which thus greatly help the planter. Indeed, it is a question whether coffee-planting could be carried on without their aid in the destruction of the bug. The black bug is Lecanium nigrum, but the female only is known. In colour it is from yellowish-grey to deerbrown, and almost black in age, and of a shield-like shape. It occurs alone, but also intermixed with the brown bug, but it is much less abundant, and therefore not demanding the planter's attention. Its occupa tion of a coffee or any other tree gives rise to the appearance of a glutinous saccharine sub stance, which has received the name of honey dew. This is either a secretion of the bug or the extravasated sap which flows from the wounded tree, or probably a combination of both. A fungus, or two fungi, the Syncladium Nietneri and Triposporium Gardneri, seem to depend on this for vegetation, as the honey-dew and the fungus disappear with the bug.—Sir J. E. Tennenes Ceylon, i. p. 261, ii. p. 248; hooker, Ilim. Jour.; O'Shaughnessy, p. 680; Ilohde's MSS.; Royle's Hindu Med. ; Wise's Hindu Med.; Eng. Cyc. ; Mad. Lit. Jour. See Bug; Coffee.