. A text-book of agricultural zoology. Zoology, Economic. SCALE INSECTS. 243 covered with a quantity of mealy powder and wool. During winter most of our outdoor scales are in the egg state; the ova are minute dust-like bodies found amongst a woolly mass under the scale. In warmer and tropical climates scales breed all the year round, and so they do in hothouses in this country. The young scale insects are active six-legged larvse (iv), which wander about for a time and then settle down and form a small scale, gradually increasing in size. If this larva is going to be-. Fio. 124.—Male Sah Jos£
. A text-book of agricultural zoology. Zoology, Economic. SCALE INSECTS. 243 covered with a quantity of mealy powder and wool. During winter most of our outdoor scales are in the egg state; the ova are minute dust-like bodies found amongst a woolly mass under the scale. In warmer and tropical climates scales breed all the year round, and so they do in hothouses in this country. The young scale insects are active six-legged larvse (iv), which wander about for a time and then settle down and form a small scale, gradually increasing in size. If this larva is going to be-. Fio. 124.—Male Sah Jos£ and Mussel scale. i, Male San JosS scale; ii, larva of same; iii, female scale; iv, larva of mussel scale ; V, female mussel scale; vi, male mussel scale, (i, ii, iii after Marlatt and Howard.) come a female, as it moults it loses its legs, antennae, &c., and degenerates into a sedentaiy apodal creature. But if the larva is going to become a male, it enters a propupal and pupal stage, a new set of legs, &c., being formed, and wings appear as bud-like outgrowths. They are very numerous and destructive in warm climates, where fruit-trees are encrusted with them. At least 1000 species have been catalogued by Mr CockereU in his recent check-list. Perhaps the most destructive is the San Jos6 scale (Aspidiotus pemicioms) (fig. 124, i, ii, iii), which. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Theobald, Frederick Vincent, 1868-1930. Edinburgh and London, W. Blackwood and sons
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1899
