INTRODUCTION. [Third Report.] TO HIS EXCELLENCY, JOHN L. BEVERIDGE, SIR-I herewith submit my third annual report upon the insects, injurious and otherwise, of the State of Illinois. It will be seen that in a part of this report I have stepped aside from the ordinary form of entomological reports of this kind, for the purpose of giving assistance to the young people of this State and others who are taking an interest in this subject, in its scientific as well as its practical relations. I have been induced to take this course by the following considerations: In the original enactment by which the office of State Entomologist was created in this State, it was made the duty of the incumbent to make an annual report upon the insects of the State, especially those injurious to the agriculturist, and also to make a general collection of the insects of the State, to be deposited at the Industrial University. As the great majority of insects are not injurious to mankind, and as a general collection of insects is merely a pretty but useless show, unless something is known of their habits and classification, it may be inferred that, in requiring such a collection to be made, the founders of this office took an enlarged view of the subject, and had an eye to the advancement of the scientific as well as the more directly practical interests of the State. By a recent enactment of the General Assembly of this State, it is required that the study of natural history shall be made a branch of the popular education. Of the great number of young people who will thus be induced to direct their attention to this subject, there must be a considerable number whose tastes will lead them to prosecute the study to a greater or less extent. This class of students will not be satisfied with the superficial knowledge which they may be able to obtain from the instructions of teachers, most of whom cannot be expected to have made a special study of the natural sciences. Especially must this be true of so extensive and difficult a science as that of entomology. It seems desirable, therefore, that there shall be some work of easy access, which shall assist them in their studies, and at the same time serve as a stepping-stone from such teaching as they may be able to obtain at the public schools, to the more learned and elaborate treatises upon this science. As many reports and treatises have already been published by the entomologists of this and other States, intended especially for the use of the practical farmer and horticulturist, in which the habits and the treatment of the most injurious insects have been pretty fully described, it seems the more admissible and proper, at this time, to give some assistance to that class of students who have the time and inclination to prosecute this subject in all its relations. In this way we may give encouragement to many young enquirers, which will stimulate them to acquire a more thorough knowledge of the subject, and one which they may hereafter turu to practical account, both for themselves and others. It must be borne in mind, however, that the main object of this office is of a directly practical nature, and if reports of a more scientific character are occasionally published, the subject should be so treated as to show, as much as possible, the connection between scientific and practical entomology. With this end in view, I have, in the present report, made the food and the food-habits of the insects treated of the basis of classification, it being in this connection chiefly that insects are injuri ous to human interests. By this means the student who has acquired the art of referring insects to their natural connections by the examination of their external structure, will be able to determine whether any species which he may have in hand be injurious, or liable to become so, by knowing the habits of the family or tribe to which it belongs. It will be seen that the present report consists of two parts: the first being devoted, as usual, to the consideration of injurious insects; and the second part being the first installment of the elementary treatise in general, referred to in the preceding remarks. In my next report I contemplate completing that part of the work which treats of the large and important order of Coleoptera, or beetles. The value of an elementary work like this, intended chiefly to aid the inexperienced student, must depend very much upon its being suitably illustrated by figures. A bill making an appropriation for this purpose was introduced into the Senate, at the recent session of the General Assembly, and passed to a third reading without opposition, but so near the close of the session that it failed to reach the lower house. It is anticipated that this bill will be passed at an early stage of the adjourned session; but the delay is a matter of regret, since the figures may require a considerable time for their preparation, and they cannot be commenced till it is known with certainty that the appropriation will be made. The cuts in the first part of this report were engraved from drawings made by Mr. C. V. Riley, State Entomologist of Missouri. The elaborate figure of Harpalus caliginosus, illustrative of the external anatomy of the Coleoptera, was engraved from a copy, reduced by photography, from a gigantic drawing made by Mr. Franklin C. Hill, of Yellow Springs, Ohio, aud kindly put at my disposal by the author. Respectfully submitted, Explanation.-a, section of an apple which has been occupied by a Codling-worm, showing the point of entrance of the worm at b, and the place of exit of the mature worm at the left hand side of the figure; e, the full grown worm; h, its head and first segment magnified; i, the cocoon; d, the pupa removed from the cocoon; f, the moth with wings closed; g, the same with wings expanded. THE CODLING-MOTH, OR APPLE-WORM. Order of LEPIDOPTERA. Family of TORTRICIDÆ. In a classification of fruit-damaging insects, in the order of the degree and extent to which they are injurious to human interests, the Codlingmoth, which is the parent of the common apple-worm, must undoubtedly hold the first place. And it would occupy this position, not only because the apple is the most valuable of fruits, but on account of the great extent of territory over which it prevails, not being limited to this country, but being also an inhabitant of the British Islands and the continent of Europe, where its habits and history were long since noticed and described. We propose, in this article, to give the results of our personal observations upon this insect for the past two or three years. We will first give a brief outline of its natural history, and then notice more particularly those parts thereof which are not generally known, or about which a difference of opinion has existed. ITS HIBERNATION. The Codling-moths pass the winter in the larva state enclosed in cocoons, which are concealed, for the most part, under the more permanent scales,or in the deep fissures of the bark or wood of the tree, in the fruit of which they were reared. Those which have been taken with the fruit into the fruit-room or cellar, are often found in great numbers under the hoops on the barrels, or in cracks of the apple bins. It is a curious circumstance in the history of this insect, that the late brood of worms, after they have enclosed themselves in cocoons, retain, as above stated, the larval form all winter, and do not change to pupa till within two or three weeks of the time when they emerge as moths in the spring. All testimony agrees upon this point. The summer brood, however, pursue the usual course, and change to pupa in the course of two or three days after they have spun their cocoons. TIME OF APPEARANCE IN THE SPRING. The moths begin to make their appearance about the time of the opening of the apple blossoms, or soon thereafter; the time varying several weeks, according to the latitude and the character of the season. Last year (1871) the moths were first noticed north of the center of this State on May 20. The present season, in the latitude of Chicago, I first saw a moth on the 12th of May, the apple trees being in pretty full blossom; but the pupa which I had kept through the winter did not begin to open till the last week in May; and Dr. James Weed, of Muscatine, Iowa, states that on one occasion, upon examining the pupa which had remained under the trap-bands through the winter, nearly all were found unchanged on the 25th of May. The time of their appearance will, of course, be earlier further south, to the same degree that vegetation is earlier; the difference in this respect being expressed with sufficient accuracy by the rule of adding or subtracting, as the case may be, about one week for each one hundred miles of latitude. TIME AND PLACE OF EGG-DEPOSIT. The moths deposit their eggs, one at a time, usually in the calyx end of the apples, as soon as they are out of the blossom. The moths themselves, on account of their smallness, the general obscurity of their coloring, and their nocturnal habits, are very rarely seen, but we know that they deposit their eggs at the calyx end because we can trace the burrow of the young worm from that part; and the other points above stated are known by a similar ex post facto method of reasoning. As insects are known often to exhibit a wonderful apparent prescience in their operations, we may fairly conclude that the final object of the habit |