. A text-book of agricultural zoology. Zoology, Agricultural; Zoology, Economic. 242 HEMIPTEKA-HOMOPTERA. room for air, and clean, vriH prevent any serious damage from this pest All rough bark should be cleared off, mosses and lichen destroyed by the washes mentioned in the Appendix, and the tree trunks painted annually Tvith some of the numerous preparations of lime, soft-soap, and paraffin. Numerous other plant-lice attack crops and fruit, among which we may mention the Corn Aphis (Siphonophora granaria); the Cabbage Louse {Aphis hrassicce), which crinkles up the cabbage leaves, forming a me
. A text-book of agricultural zoology. Zoology, Agricultural; Zoology, Economic. 242 HEMIPTEKA-HOMOPTERA. room for air, and clean, vriH prevent any serious damage from this pest All rough bark should be cleared off, mosses and lichen destroyed by the washes mentioned in the Appendix, and the tree trunks painted annually Tvith some of the numerous preparations of lime, soft-soap, and paraffin. Numerous other plant-lice attack crops and fruit, among which we may mention the Corn Aphis (Siphonophora granaria); the Cabbage Louse {Aphis hrassicce), which crinkles up the cabbage leaves, forming a mealy mass of lice ; the Plum Louse {A. pi-uni) (fig. 122), curling up the leaves of the plum; the Cherry Louse (Myzus cerasi) (fig. 121), which collect on the shoots of clierries, forming black groups and discolouring the fruit with their excrement; the Currant Aphides {Rkopdosi- phum Tibis), &c. All can be destroyed by the same washes, and need no further comment here. {Vide Appendix IL) Scale Insects (). These Hemiptera are peculiar in many respects. The females are always apterous degenerate creatures, devoid of legs and antennae, and generally lie hidden under a scale-like mass, formed by the excre- tions of the insect and the cast skins of the larva (exiivia?). They have a very long thread - like beak, which is thrust into the bark, leaf, or fruit of the plant, these insects being fixed during the whole of their life, after the larval stage is passed, in the female Fig. 123.âFem.\le San Jo.^k rpi i /,-. i -. .\ â j SCALE. (After Howard.) sex. iue mates (fag. 124:, i) are wmged, generally having one pair only, the second pair being hook-like processes. The male scale (vi) is quite different from the female scale (v) in form. Some Coccids, such as the ^Mealy bugs, form no scale, but are then. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustration
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1899
