. Cottony maple scale (Pulvinaria innumerabilis Rathvon.). Scale insects; Pulvinaria; Agricultural pests. hue. In a few days the winged males appear, but remain beneath the scale for two or three days before emerging. The females at this time have a few dorsal brownish markings and have undergone two molts. The males and females copulate in September, and soon afterward a small proportion of the females migrate to the twigs, where they insert their probosces and become fixed for the remainder of their existence, meanwhile changing from a greenish color to buff and finally brown, with a slightl
. Cottony maple scale (Pulvinaria innumerabilis Rathvon.). Scale insects; Pulvinaria; Agricultural pests. hue. In a few days the winged males appear, but remain beneath the scale for two or three days before emerging. The females at this time have a few dorsal brownish markings and have undergone two molts. The males and females copulate in September, and soon afterward a small proportion of the females migrate to the twigs, where they insert their probosces and become fixed for the remainder of their existence, meanwhile changing from a greenish color to buff and finally brown, with a slightly tessellated waxy covering. In this condition the winter is passed (fig. 3). When the sap begins to flow in the early spring the female grows rapidly, mainly because of the rapid development of great numbers of. Fig. 2.—Piolvinaria innumerabilis: a, newly-hatched young; b, female, third stage, from above; c, same, from side; d, male, third stage; <?, same, natural size, on leaf and petiole; f, same, en- larged, on leaf petiole showing two specimens parasitized—all greatly enlarged excepts (from Howard). eggs within the body. In May or early June the ovisac begins to form from the fine waxy threads exuded from the posterior spinnerets, push- ing backward and upward until the body of the female is almost vertical to the twig. Meanwhile the ovisac is gradually being filled with eggs, which hatch and undergo all the changes mentioned above. Thus, fortunately, there is but a single brood each year. PARASITES AND PREDACEOUS ENEMIES. Notwithstanding the extreme prolificacy of this insect, it is usually held in check by its many natural enemies. Doctor Howard has observed the English sparrow apparently feeding upon the full-grown scales. The twice-stabbed ladybird (Chilocorus Mvulnerus Muls.) is a common enemy of this as of other scale insects, particularly in its early stages. The smaller similarly marked Hyperaspis Mnotata Say (fig. 4) and H. signata Melsh. are also valuable
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