. Appendix to the Journals of the Senate and Assembly of the ... session of the Legislature of the State of California . FIG. 50. Pear-treePsylla) Psy lla -pyri-cola). Enlarged. FIG. 51. Larva ofPsylla 84 REPORT OF THE COMMISSIONER OF FIG. 52. Aphid? or plant lice. Winged and wing-less forms. 1 and 3 natural size. 2 and 4 greatlyenlarged. many species, some of which attack most forms of vegetation. In thisfamily we have the phylloxera and the woolly-aphis, and many otherwell-known forms, all exceedingly destructive to vegetation. The larg-est species is about
. Appendix to the Journals of the Senate and Assembly of the ... session of the Legislature of the State of California . FIG. 50. Pear-treePsylla) Psy lla -pyri-cola). Enlarged. FIG. 51. Larva ofPsylla 84 REPORT OF THE COMMISSIONER OF FIG. 52. Aphid? or plant lice. Winged and wing-less forms. 1 and 3 natural size. 2 and 4 greatlyenlarged. many species, some of which attack most forms of vegetation. In thisfamily we have the phylloxera and the woolly-aphis, and many otherwell-known forms, all exceedingly destructive to vegetation. The larg-est species is about a quarter of an inch in length, and from this theyrange down until it requires a good eye, sometimes assisted by a mag-nifying glass, to see the smaller members. Some are subterranean, y* living wholly underground; somey are aerial, living on the tops ofplants; while some are both, andpass one stage of their existenceunderground and another belonging to this fam-ily are soft-bodied, gregarious,and most numerous in the wing-less form. They have absolutelyno means of defense, being de-stroyed by thousands by everychange in the weather, blown to destruction by the winds and washedoff by the rains. They have more enemies among predaceous insectsthan
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Keywords: ., bookauthorcaliforn, bookcentury1800, bookdecade1850, bookyear1853
