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effectual; but, unfortunately, in practice, it has been destructive to the tree. Mr. Budden, Mr. Weisenhavern, and other growers inform me that in Nelson numbers of young trees had been killed by its application, and similar results have been experienced in other places. Kerosene emulsions have many advocates, but in actual practice I do not find that kerosene has the slightest advantage over castor-oil, while its application to growing vegetable-tissue is certainly attended with risk. The worst effect that I have seen attending the use of castor-oil, when applied in excessive quantities, is the retardation of leaf-development for a few days. Amongst other applications may be mentioned a mixture of soft-soap and seal-oil; covering with a thin wash of soft-soap and scraping with a wooden knife ; lime-water ; tobacco-water and sulphur, applied as a wash; covering the affected parts with clay reduced to the consistency of paint, with the additition of oil and sulphur, &c. At present, however, I have not seen any preparation equal in value to the simple mixture of castor-oil and soot. Geben Aphis (Aphis mali). A green aphis, which is occasionally met with on apple-trees, is for the present identified with this species. I have not met with any mixture in which its presence has been attended with serious results, although the leaves of infested trees are more or less curled backwards so as to afford shelter to the insect. The green aphis may be readily destroyed by syringing with soapsuds, or even with water, if ejected with sufficient force. Strong tobacco-water is an excellent wash for trees infested by aphides. It is made by pouring a gallon of boiling water over four ounces of tobacco and allowing it to stand for a few hours. A little soft-soap dissolved in the infusion would be beneficial. Tobacco of sufficiently good quality to serve as an insecticide may be grown in any part of New Zealand. In Europe and America several successive seasons may elapse without any great amount of injury being effected by Aphis mali, but in other seasons the insect becomes diffused with such rapidity that the leaves and crop are destroyed. Codlin-moxh (Garpocapsa pomonella). This pest is increasing in many parts of the colony, but at present is not generally distributed. It is most destructive in the Provincial Districts of Canterbury, Marlborough, and Nelson, but is. not confined to them; it is known in Westland, Wellington, and in several parts of the Auckland District. It was observed in the Auckland District about twelve years ago, and in Nelson about eight. Instances of its importation from Tasmania and California in affected fruit are occasionally .reported, and in all probability have been of not unfrequent occurrence. The moth is about three-quarters of an inch across when its wings are fully expanded, but the individuals vary in size to a considerable extent; the wings are grey, with dark transverse lines and black markings. The eggs are deposited singly on the apex of the ovary when the apple is in flower, or on the crown of the young fruit at a later season; the caterpillar is hatched in a few days and eats its way to the central portion of the ovary, and at first does not attack the covering which immediately protects the young seed ; it extends its burrow until it perforates the epidermis of the fruit, so that a somewhat tortuous gallery is formed, admitting air freely and facilitating the discharge of excreta. The caterpillar now returns to the core of the apple, pierces the cartilaginous covering and gains access to the seeds (pips), upon which it feeds until the apple falls, when it emerges from the fruit and ascends the trunk of the tree, taking shelter in a crevice of the bark, or beneath a tuft of lichen or moss, or below the junction of a branch with the trunk, &c, having passed fully three weeks in the caterpillar-stage. Having found a convenient resting-place it enters the chrysalis-stage, which in the early part of the season is of brief duration, the moth emerging to deposit its eggs as already described, so that two or even three generations may be developed in one season. Caterpillars leaving the fruit late in the season remain in the dormant stage during the winter, the perfect insect making its appearance the following spring. Prevention and Cure. All loose bark should be removed^ moss or lichen should be scraped off. Loose growth of every kind should be cut away so as to afford the least possible amount of shelter for the caterpillar after it leaves the fruit, and expose it for a longer period to the attacks of birds. The period at which the insect may be most easily destroyed is during the caterpillar-stage, whin advantage may be taken of its habit of ascending the trunk to capture large numbers. Bands of canvas, calico, or even stout pajier, three to five inches wide, are attached round the stem in such c, way that the upper margin fits tightly all round, while the lower margin is sufficiently loose to allow the caterpillar to creep beneath it without difficulty; the insect readily takes possession of the shelter afforded by the band, and, secreting a light web, enters upon its dormant stage. The bands should be examined once a week and the caterpillar destroyed.: usually several insects will be found under each band. Bopes of hay or straw, dipped in a mixture of tar and oil, and laid on the ground so as to surround the trunk without touching it, would doubtless prevent the caterpillar from gaining access to the tree, but wpuld dp nothing towards destroying it.