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* HISTORY OF THE INTRODUCTION OF THE GYPSY MOTH

INTO THE UNITED STATES.

The history of the introduction of the moth is quite well known to those who have been interested in the fight that Massachusetts has been making against the pest. To many of the people of Rhode Island, however, who have not until recently realized that this State may have to face a similar problem before so very long, the history is probably not so well known. It is, therefore, desirable that a short account should be given, in this report, of the time and manner in which this pest was introduced.

The exact time of the introduction of the gypsy moth has not been determined, but it is known that Mr. Leopold Trouvelot, a Frenchman who was employed as an instructor in astronomy at Harvard, and who was also somewhat of a naturalist, imported, sometime during 1868 or 1869, a number of egg clusters of this insect. His object in so doing was to attempt the breeding of a hardy silkworm. It is well known that the common silkworm is subject to a great many diseases and that, therefore, it is rather difficult to rear. The socalled "American silkworm" is also subject to a great many parasitic enemies. What Mr. Trouvelot's plans were for attaining his purpose is not exactly known, but it is supposed that he intended to make an attempt, by crossing, to produce a new and hardy insect, either from the common silkworm or from the American form, and that for this purpose he imported the gypsy moth. There is no doubt that he selected the gypsy moth for this purpose because of its well-known hardiness in its native habitat.

* Historical data for this account has been obtained largely from the reports of the Mass. work against the gypsy moth.

It is not necessary to dwell upon the fact that so far as hardiness is concerned the insect was well chosen for the object he had in view. New England people of to-day fully realize that the gypsy moth is extremely hardy and subject to but few parasitic enemies, and that were it really useful as a silk-producing insect or otherwise, it might be a great source of income to the section of the country in which it is found.

At the time that Trouvelot was doing this work he lived at No. 27 Myrtle street, Glenwood, Medford. It is known that he was fully aware of the destructive nature of the insect which he had imported, and that he sought to keep it confined. By some accident the insect escaped; just how is not absolutely known, as he had returned to France before the people actually began to realize the dangerous character of the insect. He announced the escape in a number of entomological papers and called attention to the fact that efforts should be made to destroy the insect at once. A few of the entomologists of the country, notably C. V. Riley, then State Entomologist of Missouri, recorded the appearance of the insect in this country in 1870 and stated that it was a very destructive pest in its native habitat. People generally, however, paid no attention to the presence of the insect, and it seems to have been forgotten almost entirely until about 1889, when the caterpillars became so numerous that specimens of the insect were sent to Dr. Fernald, Entomologist of the Massachusetts Agricultural College, for identification. Dr. Fernald was absent at the time, but his wife, who is also an entomologist, traced the insect in the entomological literature and found it to be the gypsy moth so well known in Europe.

During the twenty years which had elapsed since its introduction the insect had been slowly increasing and spreading from the district in Medford where it was first introduced. It had been found in certain localities in destructive numbers, but people generally had fought it without any definite idea of what kind of an insect it was, speaking of its larvæ as the "caterpillars" or "worms." It was taken by some to be the Army worm, outbreaks of which occur from time

[graphic][subsumed][merged small]

1. Full-grown caterpillars of gypsy moth. 2. Pupa. 3. Female gypsy moth laying eggs. After Kirkland.

to time throughout the country. In order that it may be realized what a scourge it had become by the time the people began to make concerted efforts to secure State aid for its destruction, the following abstracts, taken from the Special Report on the Gypsy Moth, issued by the Massachusetts State Board of Agriculture in 1897, may be of interest:

"The number of caterpillars that swarmed over certain sections of the town during the latter part of June and most of July, 1889, is almost beyond belief. Prominent citizens have testified that the "worms" were so numerous that one could slide on the crushed bodies on the sidewalks; and that they crowded each other off the trees and gathered in masses on the ground, fences, and houses, entering windows, destroying flowering plants in the houses, and even appearing in the chambers at night. The huge, hairy, full-grown caterpillars were constantly dropping upon people on the sidewalks beneath the trees, while the smaller larvæ, hanging by invisible threads, were swept into the eyes and upon the faces and necks of the passers. The myriads that were crushed under foot on the sidewalks of the village gave the streets a filthy and unclean appearance. Ladies passing along certain streets could hardly avoid having their clothing soiled, and were obliged to shake the caterpillars from their skirts. Clothes hanging upon the line were stained by the larvæ which dropped or blew upon them from trees and buildings. In the warm, still summer nights a sickening odor arose from the masses of caterpillars and pupa in the woods and orchards, and a constant shower of excrement fell from the trees. The presence of this horde of gypsy-moth larvæ had become a serious nuisance and was fast assuming the aspect of a plague. The condition of affairs at this time is best shown by the extracts from statements of residents."

"When the caterpillars were small they would spin down on their threads and blow out into the street and even entirely across it. The caterpillars were a dirty pest. You could hardly go out of doors or sit down anywhere without getting them over you. Trees were either completely stripped so that not a green thing was to be seen on them, or else were eaten so that the skeletons of the leaves only remained. The caterpillars were very numerous on a large tree behind my house. I have scraped them off by the quart on the fence and shed adjoining the tree. They clustered as thickly as bees swarm. Before caterpillar time we used to see bodies of trees plastered all over with their egg clusters. They were so thick on certain trees that they reminded me of shells at the sea-shore.' (J. H. Rogers, 17 Spring street.)

'We spent hours killing caterpillars on them (street elms.) We would get two

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