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During the Middle Ages lamentations over the destructive ravages of different species of insects are of frequent occurrence in many chronicles of those times. The means used for the destruction of insects were all, so far as we can learn, of a spiritual nature. Uhland, in his contributions to the history of poetry and legend, relates that in the fourteenth century the bishops of Chur and Lausanne pronounced the anathema over grasshoppers aud other insects. At one time a thoroughgoing procedure, according to all the rules of jurisprudence, occurred before the spiritual judge. The accused insects were summoned, and in case of nonappearance, which always occurred, unless the insects were moving to new feeding grounds and the court-house happened to be in their way, a proxy was appointed to represent the accused insects, who debated the whole subject with the accuser, after which judgment was rendered, invariably against the accused insects in the form of an excommunication, which was carried into effect only when the insects disappeared at the time of pupation.

Lesser, in his Insecto-Theology, published in London in 1799, says: We are at this day still almost in the dark with regard to those means by which we may deliver ourselves from the depredations of insects. In the Church of Rome recourse has been had to different exorcisms. Other people have fabricated amulets and talismans to which great virtues have been attributed.

Whatever credit these means may have gained with the people, they are far from having the efficacy of prayer or the worth of the remedies I am about to prescribe.

There are several ways of preventing the increase of insects. The easiest and most natural, in my opinion, are the following: By spreading on the ground ashes mixed with pigeons' or goats' dug, not only insects newly come forth, but those about to be hatchel are destroyed. By destroying the old ones we rid ourselves of the generation they would have produced, and we thus perform in an instant what we would not fail to have been employed in during the whole course of a year. But should the season anticipate our intentions, we must seek their nests in the furrows and clefts of trees. In truth, the industry of insects in choosing places in which their brood may be in safety makes it impossible but some of them will escape our search; but if in one province the country people would use stratagems on their part it is certain that they would insure that profit of which they are often frustrated.

Wecan not defend fruit trees from the ravages of caterpillars better than by carefully pruning them. By this they acquire much more sap, and, as these insects are not fond of too abundant juice, they seek elsewhere a food more to their taste. If the approach of winter obliges them to gather together in the nests which they form at the extremities of the branches, they must be taken off before the spring has made any progress.

It is possible that these means may not be practicable at all times; but then other stratagems must be fallen upon to stifle the evil in its birth. If caterpillars, ants, and other insects roam over the ground, and have not yet gotten upon the trees they are in search of, a stratum of ashes or of chalk must be laid at the bottom, which will obstruct their passage. I believe this to be infallible; for, besides that they are enemies to all constraint, they would be so embarrassed by these substances that they would not be able to disengage themselves. Twisted straw, clay, wool, and cotton are likewise successful obstacles to their ascent. Circles of them are put around the stem of the tree, and if a little resinons substance is added to them the tree will be out of danger. Let us change the case. Suppose the insects have already gotten upon the trees, plants, and bushes, the hand must be employed. But there are some times when this is done with greater success than at others, as in the morning, the evening, and during rain. These times are preferable to any other part of the day, because coolness and humidity cause insects to collect together, and then they form heaps which may be crushed at once. If, moreover, they have gained the top and the height prevents their being reached with the hand, the tree must be shaken, or a pole with rags on the end of it employed to sweep them off. But expedients must be suggested by circumstances. Another snare, the success of which is not less happy, for securing fruit trees is to lay the trunk over with glue, etc.

This represents fairly well the status of economic entomology at the end of the last century. It is undoubtedly true that the great advances made in the systematic study of insects during the last half of the eighteenth century by Linnæus, Fabricius, Denis, and Schiffermüller, Esper, Herbst, Schrank, Illiger, Scopoli, Latreille, Rösel, Panzer, Olivier, and a host of others, gave a great impetus to economic entomology, as shown by the remarkable work of Bechstein on Forest Insects, published in 1804–5; Hints to the Proprietors of Orchards, by Salisbury, published in London in 1816; Kollar's Insects Injurious to Farmers and Gardeners, published in 1836; Ratzeburg's Forest In. sects, published in 1840, with many others in Europe, while in this country there were numerous essays on injurious insects and methods of destroying or holding them in check published in the early part of this century. Harris published numerous papers on economic entomology in the New England Farmer, beginning as early as 1823, but his classic work on the Insects of Massachusetts Injurious to Vegetation appeared near the end of 1841. Fitch published his first Report on the Insects of New York in 1855, and this was followed by thirteen others. Townend Glover began his work in economic entomology in 1854 from the smallest beginnings, and we can scarcely realize that in forty years the Division of Entomology under the leadership of such brilliant men as Riley, Comstock, and Howard, with their able assistants, should now be giving to the world such masterly reports as emanate from that center.

It is not my intention, however, to speak so much of the men as of the development of methods in economic entomology. The entomologists of the present century have given us rational methods for combating insects-methods based on a more or less complete knowledge of the entire life history of the different species of which they treated, with their natural enemies and the best artificial means for their destruction that their ingenuities could devise. It was some time in the sixth decade of this century that arsenical compounds were proposed. There was bitter opposition to the use of these insecticides for a long time, and the reports of cases of poisoning, which were said to have occurred at that time, were startling in the extreme. It was even claimed that potatoes would absorb the poison to such an extent that the tubers would carry poisonous doses, so that after each meal it would be necessary to take an antidote for the poison. There is something in the human mind that leads it to accept the dreadful more readily than the prosaic, and as many believed the fabulous stories so widely circulated at that time, and for a long time after the advent of the beetle into the extreme east of this country, it was a common thing to see large fields of potatoes with persons of all ages and both sexes, each carrying a pan and stick with which they knocked the potato beetles off into the pan. Little by little, however, one farmer after another abandoned the “stick-and-pan" method and adopted the use of Paris green, till it came into very general use. This seemed to give it popularity, and there developed a readiness to use any kind of substance that bore the name of insect poison, till now the market is well stocked with a great variety of substances which are claimed to kill all kinds of insects. London purple followed closely in the wake of Paris green, and kerosene emulsion has also come into great favor for the destruction of the sucking insects, or such as do not eat the entire substance of the leaf. Thus we have several excellent insecticides which are in such general use that we may call the latter half of this century the period of insecticides.

There were men in past ages who were far ahead of their times in economic entomology, as well as in other departments of human knowledge. J.C. Schaeffer, in the third part of his work on the gypsy moth, published in 1761, discusses the methods of destroying this insect in a manner equal to Harris or Fitch, while Pastor Rimrod, in his paper published in 1781 on the same insect, handles the subject with equal ability. These papers were rare exceptions in those times, and prob. ably made little impression on the public mind, because they were so much in advance of the times. On the other hand, there are men to be found in all ages who are very much behind the times, and we may even now find men who believe every invasion of insects to be an Israelitish plague sent upon us because of the sins of the people.

In 1875 Governor Harding, of Missouri, issued a proclamation appointing a day of fasting and prayer for the interposition of Divine Providence to relieve the calamities caused by the devastation of the Rocky Mountain locust. Many of us well remember the newspaper accounts of the terrible suffering and starvation in some of the Western States caused by this insect in those times, and it need not surprise us so very much if, after having tried every plan that human ingenuity could devise, they should in their final extremity have appealed to Almighty God. This is about the way with us all. In the supreme hour, when everything else fails, we remember and appeal to the Overruling Providence. If I may be permitted here to express a personal opinion along these lines, I would say that while it is exceedingly helpful to the human soul to trust in the Divine Creator of heaven and earth, I can not rid myself of the conviction that in economic ento. mology God helps those most who most help themselves—those who make themselves most conversant with His laws, as exhibited in the life and habits of the insects they have to deal with, as well as the climatic and other conditions which affect them, in fact the whole environment, and make the best possible use of this knowledge in their attempts to destroy insects or hold them in check.

Last year the chairman of the board of selectmen in a Massachusetts town refused to use any of the public money for the protection of the trees along the streets from the cankerworms, because the idea of fighting insects was “agin natur.” This year that saine man's apple trees are as bare of leaves as though a fire had run through his orchard, and therefore I am of the opinion that it will be “agin natur” for that man to gather a crop of fruit from his trees this fall.

The establishment of agricultural experiment stations by the General Government in 1888, with entomologists in a large proportion of them, gave a wonderful impetus to the study and development of economic entomology in this country. At first it was thought that because of the lack of a sufficient number of well-trained and experienced entomologists to fill these positions very poor work would be done until a sufficient time had elapsed for young men to become educated and trained in this line, when they would crowd the more inferior material to the wall. To me it has been a matter of pleasure and pride to see the young men coming to the front so rapidly, filling these places so satisfactorily, and publishing bulletins and other papers of such rare value. I am deeply impressed with the idea that unless those of us

. who are older and have been in the work for a long time look well to our laurels we may soon find ourselves crowded up against the displacement wall and younger and perhaps more competent men standing ready to take our places. Nevertheless, it is a great pleasure to me to help and encourage any promising and modest young man who is thoroughly in earnest in the study of entomology.

In this connection I can not too highly commend the course taken by some of our economic entomologists who in connection with their other work make a systematic study of some family or group of insects or study thoroughly the anatomy or embryology of one or more species. Even a fragment of such study will some time prove useful, since it forms a link in the great chain of human knowledge, and each link forged into it tends to strengthen and make it more useful. I have no sympathy with those who work only in one restricted field till they become so narrow that they can appreciate nothing except what is found in their own extremely narrow groove. The entomologist who broadens the horizon of his observations becomes better able to grasp and comprehend the great problems presented to him.

With the discovery of insecticides came the necessity for various kinds of apparatus for the application of them, and here again there has been an evolution which is still going on. Many of the spraying pumps, nozzles, and other apparatus first placed on sale are no longer in use, but greatly improved kinds are on the market, and investigations are still giving us improvement after improvement, some of which, unfortunately, are no improvement at all. On the whole, however, the insecticide apparatus of to day is greatly superior to that of a decade ago.

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It seems to me that in the future development of economic entomology we have need of the chemist and of the physiologist. Some work has already been done on the use of Paris green and lime, but the results do not appear to be beyond question. It is to be hoped that the investigations already made in the work on the gypsy inoth, as well as those not yet completed, may prove of value in operating on other species of insects. This work has already given us arsenate of leail and arsenate of barium as insecticides, and investigations are still going on concerning the nature of the intestinal secretions of this insect and the poisous that will most readily react on these secretions and thereby destroy it. It may be that investigations by the chemist and physiologist, working together along these lines, may give us something in the future superior to anything in use at the present time. The three most important characteristics of an insecticide which must be kept constantly in mind when investigating a new or untried poison, are: (1) It must kill the insects quickly, the more quickly the better; (2) it must not injure the foliage when used in as large proportion as one may need for the destruction of the insects; (3) it must be cheap enough to come into general use. There are other considerations of more or less importance, as the ease with which the insecticide may be applied, its liability to clog the nozzles or corrode and injure the apparatus, and, in fact, any objection that will prevent the substance from coming into general use.

After one has made valuable investigations and discoveries in economic entomology it remains for him to publish his discoveries in such a place as will be accessible to those who most need this information, and in such a manner as to lead them to read the paper carefully and intelligently. I know very well that there are thousands of persons who receive our bulletins who do not even look them over. I was told by the editor of one of our leading agricultural papers a few years ago that he sent out a circular letter to his subscribers asking what changes, if any, they would like to have him make in his paper, and a large percentage of them requested him to give them more stories; and I have sometimes wondered if the information given in our bulletins were presented in the form of a strongly sensational novelette they would not get a much more general reading. Personally, I can not adopt the plan, as I have no skill as a novelist.

After all, it is more important to investigate and make new and valuable discoveries, even if they are not so widely read at first, for they will be taken up by others and disseminated far and wide, and in time the useful information will become filtered through the public mind.

There is often need of legislation to aid in the carrying out of the recommendations of the economic entomologists, and this is an important question at the present time. There is no law in Massachusetts to prevent a nurseryman or anyone else from selling and distributing

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