Page:Popular Science Monthly Volume 45.djvu/700

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THE POPULAR SCIENCE MONTHLY.

it, kept on increasing, and some ten years ago I felt that the work of this particular species and of others which seriously affected the fruit-growing interests of southern California, justified the establishment of agencies there. Up to this time no special entomological efforts have been made by the Government on behalf of the fruit-growers of the Pacific coast. Through agents stationed—the one at Los Angeles, the other at Alameda—a course of elaborate experiments was undertaken as to the best means of treating the insects affecting the orange there, and more particularly this fluted or cottony-cushion scale. During the progress of these investigations, however, the fact impressed itself upon my mind that we had here an excellent opportunity of calling to our aid its own natural enemies; for while there were at first some doubts as to the origin of this icerya, the question was finally settled to my satisfaction that it was of Australian origin, that in its native home it was not a serious pest, but was kept subdued by natural checks.

A clause in the bill appropriating for the division of entomology prohibited the sending of agents abroad and prevented at the time independent action by the Department of Agriculture; but with the co-operation of the Department of State an arrangement was finally made by the Hon. Frank McCoppin, United States Commissioner to the Melbourne Exposition, whereby two agents of the Division of Entomology were sent to Australia, one of them specially charged with the study and importation of the natural enemies of this insect.

It was thus that Mr. Albert Koebele, in the fall of 1888, was sent to Australia for this special purpose. The history of Mr. Koebele's efforts has been detailed from time to time in Government publications and in the press, especially that of California. It suffices to state that a number of living enemies, both parasitic and predaceous, were successfully imported, but that one of them (Vedalia cardinalis) proved so effective as to throw the others entirely into the shade and render their services really unnecessary. It has so far not been known to prey upon any other insect, and it breeds with surprising rapidity, occupying less than thirty days from the laying of the eggs until the adults again appear. These facts account for its exceptionally rapid work, for in point of fact within a year and a half of its first introduction it had practically cleared off the fluted scale throughout the infested region. The expressions of two well-known parties may be quoted here to illustrate the general verdict. Prof. W. A. Henry, Director of the Wisconsin Agricultural Experiment Station, who visited California in 1889, reported that the work of the vedalia was "the finest illustration possible of the value of the department to give the people aid in time of distress, and the distress