An Account of the Insects Noxious to Agriculture and Plants in New Zealand The Scale Insects (Coccididae)
9781465639929
118 pages
Library of Alexandria
Overview
The common English name for this family—"scale-insects"—is not very appropriate. Some few of them have the appearance of small thin scales on leaves or twigs, but many have not. Nor are the German appellations—"gall-insekten" or "schild-lause"—more appropriate. Gardeners have given to some of them the name of "mealy-bug," which, although decidedly neither elegant nor euphonious, very fairly represents the character of that particular portion of the family. The origin of the name "Coccididæ," or, as abbreviated often in this volume, "Coccids," is found in the old Greek word "[Greek: kokkos]," denoting a rich red dye, which was much admired by the Greeks and Romans, and which was procured from the insect now known as Kermes vermilio (the Coccus ilicis of Linnæus). When the cochineal insect was discovered in Mexico it soon overpowered all the others, producing commercial dyes, and from it has come the title "Coccid," now applied to the whole family. Cochineal itself has of late years been pushed aside to a great extent by the aniline (coal-tar) dyes; yet it is still used for many purposes. This insect lives on the leaves of cactus. Amongst the New Zealand species described in this work will be found one, Dactylopius alpinus, which produces a red dye similar to, though probably not equal to, cochineal. Before the discovery of aniline dyes it might possibly have been worth while to cultivate this insect for its dye; but this would scarcely answer now. The Coccididæ are, in some parts of the world, very injurious to vegetation. They seem to affect principally the warmer temperate regions. California, Florida, the Cape of Good Hope, the southern parts of Australia, Southern France and Northern Italy, and New Zealand are countries in which they are found out-of-doors in the greatest numbers. In England they are less troublesome in the open air, though in greenhouses and hothouses they abound; but, in places under glass, every gardener ought to be able to get rid of them without difficulty. For its extent New Zealand seems to furnish a larger number than any other country. The humidity of its climate and the absence of anything like severe winters in most parts of it are quite congenial to Coccids; and there is scarcely a tree in its forests or in its gardens, whether native or introduced, which is not subject to their attacks. It has not been thought necessary to include in this work a list of the books and essays written on this family of insects. The list would be a very long one; but, besides that many of the books would not be obtainable here, it would be found that very many authors have done nothing more than copy—often quite blindly and unintelligently—what others had said before them; moreover, most of them are out of date. The student or the horticulturist desiring to know more about Coccids not found in New Zealand may find full details in the reports of the Agricultural Department of the United States Government, in Dr. V. Signoret's "Essai sur les Cochenilles" (Paris), in papers by Miss Emily Smith (American naturalist, 1878-80), &c. The American Departmental Reports of Professors Riley and Comstock, Mr. Hubbard, and Mr. L. Howard contain most valuable information. English works on the subject are mostly fragmentary or inaccurate; but Mr. Douglas, of Lewisham, has lately begun to discuss the Coccids in England in a systematic manner, and probably before long others will follow suit. In India, Mr. T. W. Atkinson, of Calcutta, is studying the family.
