The list of plants attacked is a long one, but the following may be mentioned:--Acacia, hawthorn, quince, privet, poplar, almond, apricot, cherry, plum, peach, pear, apple, gooseberry, currant, roses, willow, ash, elm. The female San José scale is circular in outline, having a diameter of about one-twenty-fifth of an inch; in profile it has the form of a flat cone with a crater-like depression at the apex, in the centre of which lies a minute pimple-like prominence; the immature scales are smaller and whitish in colour, while the male scale is elongate-oval in outline, with the crater-like depression toward one end. The individual scales are greyish and are readily overlooked, but when well established upon a tree they form an incrustation giving a characteristic dull silver-grey appearance to the tree; bark, fruit and leaves are infested. A characteristic feature of San José scale infection is the discolouration of the plant tissues immediately surrounding each insect, which turn a distinct red or purple, giving at once an indication that this scale is present. The winter is passed by the insect in almost a mature state; on the advent of spring, development to maturity continues, when, after mating, the females give birth to living young over a period of several weeks. The young reach maturity and commence to reproduce five to six weeks from birth, there being several generations in the course of a season. The average number of young produced by each female has been found to be about 400. [Illustration: FIG. 7. (1) Golden Oak Scale; (2) Apple Mussel Scale; (3) Black Scale; (4) Cabbage Tree Scale; (5) San José Scale; (6) Apple Mussel Scale; (7) Oleander Scale; (8) and (9) Rose Scale. _Photographs by W. C. Davies, Cawthron Institute._] Natural enemies in New Zealand are two species of hymenopterous parasites, _Aphelinus fuscipennis_ and _A. mytilaspidis_, the latter also attacking the apple mussel scale. Ladybird beetles also feed upon the insect. Control requires close attention, and can be effected by the application of lime-sulphur in the dormant season, when it is essential to apply a strong wash to kill off as many scales as possible before reproduction commences in the spring. At bud movement further applications are necessary to destroy the young insects. RED ORANGE SCALE(_Chrysomphalus aurantii_).--The red orange scale is distributed throughout the world, and is especially abundant in tropical and sub-tropical regions, the most southern limit being New Zealand. As a major pest it is peculiar to citrus, but infests to a minor extent other plants--_e.g._, plum, apple, pear, quince, grape, fig, euonymus and rose. So far it has been found only on citrus in New Zealand, it being well established in the Auckland province, and also in the South Island on Banks Peninsula. It is very often found on imported oranges and lemons.