PLATE I. A MANUAL FOR THE STUDY OF INSECTS JOHN HENRY COMSTOCK Professor of Entomology in Cornell University and in Leland Stanford Junior University ANNA BOTSFORD COMSTOCK Member of the Society of American Wood-Engravers ITHACA, N. Y. COMSTOCK PUBLISHING COMPANY 1895 Copyright, 1895, JOHN HENRY COMSTOCK. PREFACE. FOR many years the most pressing demand of teachers and learners in entomology in this country has been for a handbook by means of which the names and relative affini- ties of insects may be determined in some such way as plants are classified by the aid of the well-known manuals of botany. But, as the science of entomology is still in its infancy, the preparation of such a handbook has been im- possible. Excellent treatises on particular groups of insects have been published ; but no general work including analyt- ical keys to all the orders and families has appeared. It is to meet this need that this work has been prepared. The reader must not expect, however, to find that de- gree of completeness in this work which exists in the man- uals of flowering plants. The number of species of insects is so great that a work including adequate descriptions of all those occurring in our fauna would rival in size one of the larger encyclopaedias. It is obvious that such a work is not what is needed by the teachers and students in our schools, even if it were possible to prepare it. An elementary work on systematic entomology will always of necessity be re- stricted to a discussion of the characteristics of the orders and families, and descriptions of a few species as illustrations. Complete synopses of species will be appropriate only in works treating of limited groups. It is believed, therefore, that it would not be wise to materially change the scope of iii IV PREFACE. the present work even if it were possible to describe all of our species. Although much pains has been taken to render easy the classification of specimens, an effort has been made to give the mere determination of the names of insects a very sub- ordinate place. The groups of insects have been fully char- acterized, so that their relative affinities may be learned ; and much space has been given to accounts of the habits and transformations of the forms described. As the needs of agricultural students have been kept constantly in view, those species that are of economic importance have been described as fully as practicable, and particular attention has been given to descriptions of the methods of destroying those that are noxious, or of preventing their ravages. An effort has been made to simplify the study of in- sects as much as possible without sacrificing accuracy in the descriptions. Only such morphological terms have been used as were necessary to accomplish the object of the book in a satisfactory manner. And so far as possible a uniform nomenclature has been used for all orders of insects. The fact that writers on each order of insects have a peculiar nomenclature has been a serious obstacle to the progress of entomology ; this is especially true as regards the nomen- clature of the wing-veins. It has been necessary for the student in passing from the study of one order of insects 'to that of another to learn a new set of terms ; and in many cases writers on a single family have a peculiar nomenclature. The present writer has endeavored to remove this obstacle by making a serious study of the homologies of the wing-veins, and by applying the same term throughout the work to homologous veins. The result is that the student is required to learn only one set of terms ; and in applying these terms there will be brought to his attention'in a forci- ble manner the peculiar modifications of structure charac- teristic of each order of insects. Heretofore, with a differ- ent nomenclature for the wing-veins of each order such a PREFACE. V comparative study of the various methods of specialization has been beyond the read of any but the most advanced scholars. The principal features of the method of notation of wing-veins proposed by Josef Redtenbacher has been adopted. But as the writer's views regarding the structure of the wings of primitive insects is very different from those of Redtenbacher, the nomenclature proposed in this book is to a great extent original. The chief point of difference arises from the belief by the present writer that veins IV and VI do not exist in the Lepidoptera, Diptera, and Hymenoptera ; and that, in those orders where they do exist, they are secondary developments. The reasons for this be- lief are set forth at length in my essay on Evolution and Taxonomy. In this essay there was proposed a new classification of the Lepidoptera, which was the result of an effort to work out the phylogeny of the divisions of this order. This classi- fication has been further elaborated in the present work. In the other orders but few changes have been made from the more generally accepted classifications. It is more than probable however, that when the taxonomic principles upon which this classification of the Lepidoptera is based are ap- plied to the classification of the other orders radical changes will be found to be necessary. A serious obstacle to the popularization of Natural His- tory is the technical names that it is necessary to use. In order to reduce this difficulty to a minimum the pronuncia- tion of all of the Latin terms used has been indicated, by dividing each into syllables and marking the accented syllable. In doing this the well-established rules for the division of Latin words into syllables have been followed. It seems necessary to state this fact in order to account for differences which exist between the pronunciations given here and some of those in certain large dictionaries recently published in this country. VI PREFACE. Nearly all of the wood-cuts have been engraved from nature by the Junior Author. As the skill which she has attained in this art has been acquired during the progress of the work on this book, some of the earlier-made illustra- tions do not fairly represent her present standing as an engraver. But it does not seem worth while to delay the appearance of the book in order to re-engrave these figures; especially as it is believed that they will not be found lack- ing in scientific accuracy. The generous appreciation which the best engravers have shown towards the greater part of the work leads us to hope that it will be welcomed as an important addition to entomological illustrations. Although the chief work of the Junior Author has been with the pencil and graver, many parts of the text are from her pen. But in justice to her it should be said that the plan of the book was changed after she had finished her writing. It was intended at first to make the book of a much more elementary nature than it is in its final form. It has seemed best, however, to leave these parts as written in order that the work may be of interest to a wider range -of readers than it would be were it restricted to a uniform style of treatment. The figures illustrating the venation of the wings of in- sects have been drawn with great care under the writer's direction by Mr. E. P. Felt and Mr. R. H. Pettit. About one half of those in the chapter on Lepidoptera were drawn by Mr. Felt ; the others in this chapter and those in the chapters on Diptera and Hymenoptera were drawn by Mr. Pettit. I wish also to acknowledge the help of my Assistant Mr. A. D. MacGillivray, to whom I am indebted for much aid in bibliographical researches and in many other ways ; also, that of Dr. A. C. White of the Cornell University Library, who has generously given much time to determining the etymologies of many of the more obscure words the pro- nunciations of which are indicated in the text. PREFACE. Vli To the authorities of Cornell University the authors of this book are under deep obligation for aid and encourage- ment. The preparation of the work would not have been possible but for the liberal grants which they have made for the purchase of specimens and books. JOHN HENRY COMSTOCK. ENTOMOLOGICAL LABORATORY, CORNELL UNIVERSITY, December, 1894. CONTENTS. I. Zoological Classification and Zoological Nomenclature... i II. Insects and their Near Relatives : Branch ARTHROPODA ; Class CRUSTACEA, Crabs, Lobsters, Crayfish, and Others; Class ARACHNIDA, Spiders, Scorpions, Mites, and Others; and Class MYRIAPODA, Centipedes and Millipedes 9 III. Class HEXAPODA or Insects: Characteristics of the Class; Metamorphoses of Insects ; External Anatomy of In- sects ; Internal Anatomy of Insects ; Table for Deter- mining the Orders of Insects ; List of the Orders of Insects 48 ' IV. Order THYSANURA, Bristle-tails, Spring-tails, Fish- moths, and Others 82 V\Order EPHEMERIDA, May-flies 86 VI. Order ODONATA, Dragon-flies : 89 VII. Order PLECOPTERA, Stone-flies 93 VIII. Order ISOPODA, Termites or White-ants 95 IX. Order CORRODENTIA, Book-lice and Others 98 X. Order MALLOPHAGA, Bir4~lice 100 XI. Order DERMAPTERA Earwigs 102 XII. Order ORTHOPTERA, Cockroaches, Crickets, Grasshop- pers, Locusts, and Others 104 XIII. -Order PHYSOPODA, Thrips 119 XIV. Order HEMIPTERA, Bugs, Plant-lice, Bark-lice, and Others 121 XV. Order NEUROPTERA, the Dobson and Others 175 XVI. Order MECAPTERA, Scorpion-flies 184 XVII. Order TRICHOPTERA, Caddice-flies 186 XVIII. Order LEPIDOPTERA, Moths, Skippers, and Butterflies.. 191 XIX. Order DIPTERA, Flies 413 XX. Order SIPHONAPTERA, Fleas 490 XXI. Order COLEOPTERA, Beetles 494 XXII. Order HYMENOPTERA Bees, Wasps, Ants, and Others. . 599 INDEX AND GLOSSARY — 679 ix EXPLANATION OF PLATES. PLATE I. (FRONTISPIECE.) FIGURE PAGE 1. The Carpet Beetle 539 2. The Twelve-spotted Diabrotica 577 3. The Adalia bipunctata 535 4. The Silver-spotted Skipper 370 5. The American Copper 390 6. The Red Admiral 401 7. The Painted Beauty 401 PLATE II. (PAGE 68.) THE INTERNAL ANATOMY OF A CATERPILLAR. PLATE III. (PAGE 70.) THE INTERNAL ANATOMY OF A COCKROACH. PLATE IV. (PAGE 343.) PSEUDOHAZIS HERA. PLATE V. (PAGE 353.) FIGURE PAGE 1. The Luna Moth 353 2. The Crinkled Flannel-moth , 218 PLATE VI. (PAGE 389.) 1. The Spring Azure 391 2. The Green Comma 404 3. The Hop-merchant 405 4. The Banded Elfin 393 5. The Mourning-cloak 403 6. The Olive Hair-streak , 393 7. The Spring Azure 391 8. The Violet Tip -. 405 A MANUAL FOR THE STUDY OF INSECTS. CHAPTER I. ZOOLOGICAL CLASSIFICATION AND NOMENCLATURE. I. Zoological Classification. (For advanced students. ) IN order that the myriad forms of animals may be studied with facility some system of classification is necessary. And now that we have learned that there exists a blood-relationship between the differ- ent kinds of animals, that system which most clearly expresses this relationship is doubtless the best. This system is termed the Natural Classification . It is now generally believed that long ago, in early geological times, there existed on the earth only very simple animals and plants; and that from these simple beginnings more and more complex forms have been developed. This growth in complexity has taken place in different descendants of these simple primitive beings in very differ- ent ways. Thus while it is probable that the first animals lived in water, and very many still do so, others have become adapted to life on the land, and in still others organs have been developed by which they can fly through the air. And under each of these conditions we find a great diversity of forms, each fitted for some special mode of life. 2 THE STUDY OF INSECTS. The diversity of forms of animal life is much greater than is com- monly supposed. A competent authority has estimated that there are now living on the earth more than one million species of animals. And these are merely the surviving descendants of immense series of beings that have existed in past geological times, the remaining tips of a great genealogical tree, of which many twigs and branches have perished. The common figurative use of the word tree in this connection expresses well the convergence of the lines of descent toward the common ancestor from which existing forms have descended. But in one respect it may be misleading. If an ordinary tree be ex- amined, the tip of one branch will closely resemble that of any other branch of the same tree. But in this figurative genealogical tree we must imagine a very different state of affairs. Here the law of growth is constant change ; each branch grows in its own individual way; and each twig of each branch bears fruit peculiar to itself. The changes, however, are gradual ; and thus the tips of closely-con- nected twigs will be similar though not identical ; while the tips of two branches that separated early in the growth of the tree will be very different. It is the effort of the systematist, one who studies the classification of animals and plants, to work out the relations which exist between the various tips of the genealogical tree. This study when carried to its fullest extent includes not only the study of existing forms of life, but also the study of those that have perished, the trunk-forms from which existing forms have descended. This, however, is a very difficult matter; and as yet only the beginnings of the Natural Classification have been made. See pp. 139 to 204. If we accept this theory of descent, now almost universally ac- cepted by naturalists, it is evident that when we take into account all the forms of life that have existed we cannot classify animals into well-marked groups; for as the modification in form is gradual, series of connecting links have existed between any two forms that might be selected. But practically the student that confines his attention to the study of living forms can classify these forms into more or less well- marked groups, for many of the connecting links have perished ; in fact, the groups of living animals and plants are so distinct that it is only in recent years that naturalists have come to understand the blood-relationship referred to above. We find that the Animal and Vegetable Kingdoms are made up of a vast assemblage of individuals, each the offspring of parents similar ZOOLOGICAL CLASSIFICATION. 3 to itself, and each in turn producing similar offspring. Although the offspring is never exactly like either parent, the degree of variation in a single generation is slight. And thus we find that there exist large numbers of individuals which very closely resemble each other. Such a collection of individuals is termed in popular language a kind, in scientific language a species. Thus the kind of pine trees known as pitch-pine is a species; and scrub-pine, still another. In the same way the name sparrow-hawk indicates a kind or species of hawk; and pigeon-hawk, another species. Roughly speaking, a species is a collection of individuals which resemble each other as closely as the offspring of a single parent. For example, if any two pitch-pines be studied, nothing will be found to indicate that they may not have sprung from seeds grown upon the same tree. On the other hand, if a pitch-pine and a white-pine be carefully compared, they will be found so different that no competent observer would believe that they had a common parent. Unfortunately this mode of defining the limits of a species cannot be depended upon. Many instances are known where forms of animals or plants living in widely-separated regions differ so greatly that they have been considered distinct species until more extended collections in the intermediate regions have brought to light series of intermediate forms, which connect the two so-called species so closely that it is impossible to say where the one ends and the other begins. The only definite way of determining whether two forms are specifically distinct is to determine whether they naturally interbreed or not. We find among wild animals a sort of race prejudice which keeps the members of different species from pairing, although they may do so when demoralized by domestication. Except in the case of very-closely-allied species, the pairing of individuals of different species results in no offspring or in the production of sterile offspring. This grouping of individuals into species not only facilitates our study of Natural History, but expresses certain important facts of inheritance and reproduction. A second and somewhat similar step is made by grouping species into genera. We find that there exist groups of closely-allied species, species that resemble each other in all of the more important characters, and differ among themselves only in what are known as the specific characters. Such a group of species is termed a genus. Thus all the different species of pine taken together constitute the genus pine, or Pinus, as it is termed by botanists. There are many species of oak, 4 THE STUDY OF INSECTS. as red-oak, live-oak, and water-oak. All of the species of oak taken together constitute the genus Querciis of botanists. Several species of hawks and falcons are classed together by zoologists as the genus Falco. The genera in turn are grouped into families. Thus the pines, the spruces, and the larches resemble each other quite closely, and are classed together as the Pine Family (Abietinece) ; the falcons, hawks, kites, and eagles are classed together as the Falcon Family (Falconidce). Closely-allied families are grouped together to form orders. The Pine Family, the Cypress Family, and the Yew Family comprise the Order Conifera, or cone-bearing plants, of botanists. The Owl Fam- ily (Strigidce), the Falcon Family (Falconidce), and the Vulture Family ( Vulturida) constitute the Order Raptores, or Birds of Prey. Closely-allied orders are grouped together to form classes. Thus all the orders of birds taken together constitute the Class Aves or Birds. The classes are grouped into branches, which are the principal divisions of the Animal Kingdom.* In studying the different forms of animals it is found that there are several distinct types of structure. Some animals are built upon one plan or structure, and others on other plans. All animals built on the same plan are said to belong to the same Branch. Thus the back-boned animals comprise the Branch Vertebrata ; the clams, oysters, snails, cuttle-fish, and certain other allied forms comprise the Branch Mollusca ; and the insects, spiders, centipedes, lobsters, and their near relatives comprise the Branch Arthropoda. All the branches of animals taken together constitute the Animal Kingdom. It is not possible to lay down rules by which these different groups of animals can be limited. For, as has been shown in our discussion of species, all have been connected in past time by intermediate forms But notwithstanding this, each of the terms given above (Branch, Class, Order, Family, Genus, and Species) expresses a pretty definite conception, which the student will learn to comprehend by practice in classifying animals. But the sequence in rank of these groups should be learned at the outset. Beginning with the most compre- hensive it is as follows : * The principal divisions of the Vegetable Kingdom are not termed Branches ; hence we will not make further use of botanical illustrations in this connection. ZOOLOGICAL NOMENCLATURE. Animal Kingdom. Branch: or Subkrngdom. Class. Order. Genus. Species. Individual. It is sometime desirable to indicate other groups than those named above. Thus a family may be divided into subfamilies, or an order into suborders. And occasionally an even more minute division is made. Thus several closely-allied families may be grouped together as a superfamily, a group of lower rank than a suborder. The follow- ing table includes all the grades of groups now commonly employed : Kingdom. Branch or Subkingdom. Class. Subclass. Superorder. Ojder. Suborder. Superfamily. Family. Subfamily. Genus. Subgenus. Species. Subspecies. Variety. Individual. II. Zoological Nomenclature. (For advanced students.) At the beginning of his studies of Natural History the student is met with what is to him a new and strange set of names. These names are often long. In form they belong to a dead language, with which, in these days, even many educated people are unfamiliar. It is not strange that we often hear complaint respecting the difficulty of this nomenclature. O THE STUD Y OF 1ATSECTS. A little study of the matter, however, is sufficient to show the necessity for scientific names. The common names of animals will not answer our purpose ; for the same name is often applied to widely different animals in different localities, while a single species of animal is known by totally different names in different sections of the country. In order that information respecting animals may be recorded so that there need not be any doubt regarding the animal to which refer- ence is made, it is necessary that each species or group of species should have a distinct name by which it shall be known by naturalists in all parts of the world. Therefore, to each branch, class, order, family, genus, and species which has been described there has been given a special name, by which it is known, and which pertains to this group alone. As this nomenclature is used by all naturalists of whatever nation- ality, it is necessary that the names should be in a language which can be understood by all. As Latin was the language in which most scientific books were written at the time this nomenclature was estab- lished, that language was chosen as the universal language of science; and the rule has been adopted that all names of animals and plants shall be Latin, or Latin in form. The name of a species consists of two words — the name of the genus to which the species belongs, followed by an adjective indicat- ing the particular species ; for in Latin an adjective follows the noun which it qualifies, instead of preceding it as in English. Thus the scientific name of the Pigeon-hawk is Falco columbartus; that of the Sparrow-hawk is Falco spar-verius ; and that of the Prairie-falcon is Falco mexicanus. In the case of many species we find well-marked subspecies or geographical races which it is desirable to distinguish by name. Thus the Pigeon-hawk occurs over the whole of North America. But we ^California to Sitka, constitute a distinct geographical race known as the Black Merlin. As the Black Merlin and the typical Pigeon-hawk intergrade, they constitute a single species, which is known as Falco columbarins. To the Black Merlin has been applied the subspecific name suckleyt. When, therefore, it is desired to refer to the Black Merlin as distinguished from the typical Pigeon-hawk the term Falco columbartus suckleyt is used. If reference is to be made to the typical Pigeon-hawk as distinguished from the Black Merlin, it is designated as Falco columbarius columbartus. In writing long names like those given above they are frequently ZOOLOGICAL NOMENCLATURE. J abbreviated if the context is such that the abbreviations will be read- ily understood. Thus the name of the Black Merlin may be written Falco c. suck ley i or F. c. sue k ley t. Subspecific names are used by entomologists not only to distinguish geographical races, but also to distinguish the different forms of dimorphic and polymorphic species. A good illustration is afforded by a certain species of Swallow-tail Butterfly common in the Atlantic States. This species exists under two distinct forms ; one of these is yellow marked with black, and has long been known as Jasoniades lurnus ; the other is almost entirely black, and has been known as Jasoniades glaucus. At first it was supposed that these were different species ; but in recent years the two forms have been bred from eggs laid by the same female. It is thus evident that the two forms repre- sent a single species. And as the form glaucus was first described its name is given to the species, which is now known as Jasoniades glaucus. This name Jasoniades glaucus is used when reference is made to the species as a whole. But if one wishes to refer to the black form alone, it is distinguished as Jasoniades glaucus glaucus ; while the yellow form is distinguished as Jasoniades glaucus turnus. In the illustrations just given the dimorphism occurs in the same generation. But many instances are known where the dimorphism is seasonal. Thus in the case of certain insects which pass through two or more generations in the course of a year, the different generations, or some of them, differ markedly in form or coloring from the others. These differences in many cases are so great that the different genera- tions of the same species were believed to be distinct species till they were bred from each other. It is therefore often desirable to distin- guish these different forms by subspecific names. Thus iphiclides ajax is a species of Swallow-tail Butterfly which exists under three distinct seasonal forms: an early spring form, /. ajax marcellus ; a late spring form, 7. ajax telamonides ; and a summer form, /. ajax ajax. The name of a genus or of a subgenus is always a single word, and should be a noun in the singular number and nominative case. The names of all groups of genera (i.e., families, orders, classes, and branches) consist each of a single word ; and this word should be a plural noun in the nominative case. The following practices regarding the forms of zoological names are now almost universally followed : The names of all groups in zoology, from kingdom to subgenus inclusive, are written and printed with a capital initial letter. 8 THE STUDY OF INSECTS. Specific and subspecific names are written and printed with a small initial letter. Thus in writing the name of a species the generic name is capitalized, the specific name not ; eg., iphtclides ajax. The names of families end in idee ; the names of subfamilies, in ina. It will aid the student greatly in the pronunciation of family and subfamily names to know that the /of -idee in family names is short, and consequently the accent falls on the syllable preceding this letter ; while the / of -ince of subfamily names is long, and is conse- quently accented.* Numerous examples are given in the following pages. * This in accordance with the rule of Latin grammar that in words of more than two syllables the penult if long is accented; but if the penult is short the accent falls on the antepenult. CHAPTER II. INSECTS AND THEIR NEAR RELATIVES. Branch ARTHROPODA (Ar-throp'o-da). The Arthropods (Arl thro-pods). If an insect, a spider, a scorpion, a centipede, or a lobster be examined, the body will be found to be composed of a series of more or less similar rings or seg- ments joined together; and some of these segments will be found to bear jointed legs (Fig. i). All the animals possessing these characteristics are classed together as the Branch Arthropoda. A similar segmented form of the body is found among worms ; but these are dis- tinguished from the Arthropods by the absence of legs. It should be remembered that many animals commonly called worms, as the tomato-worm, apple-worm, etc., are not true worms, but are the larvae of in- sects (Fig. 2). The angle-worm is the most familiar example of a true worm. The Branch Arthropoda is the largest of the branches of the Animal Kingdom, including many more known species than all the other branches taken together. Our common representatives are distributed among four classes: these are the Crustacea, the Arachnida, the Myriapoda, and the Hexapoda. The 9 FIG. i.— An insect show- ing segmented form of body. 10 THE STUDY OF INSECTS. first three classes are briefly discussed in this chapter ; the fourth comprises the Insects, and is the subject of the remaining parts of this book. FIG. 2. — A larva of an insect. The following table will enable the student to distin- guish the classes of the Arthropoda.* TABLE OF CLASSES OF THE ARTHROPODA. A. With two pairs of antennae and at least five pairs of legs. Aquatic animals breathing by gills, p. 11 CRUSTACEA. AA. With one pair of antennae or with none. Air-breathing ani- mals. The number of legs varies from six to many. *The following is the method of using the analytical tables given in this book: Read carefully the statement of characteristics given opposite A and AA. respectively, and by examining the animal to be classified determine which is true of this animal. This will indicate in which division of the table the name of the group to which the animal belongs is to be looked for. If this division of the table is subdivided, pass to B and BB (also to BBB if it occurs) in this division and determine in a like manner under which the animal belongs. Continue in this way, passing to the letters C, D, E, etc., in regular order till the name of the group is reached. Then turn to the page indicated and read the description or the group given there, comparing the specimens with the description. It should be borne in mind that an analyt- ical table is merely an aid to the determination of groups. As the groups that we recognize are not always sharply limited in nature, we cannot expect to be able in every case to find characters that will serve to distinctly separate them in a table. Therefore when a student has determined by the aid of a key to what group a species seems to belong, he should verify this determi- nation by a study of the characters of that group given in the detailed dis- cussion of it. INSECTS AND THEIR NEAR RELATIVES. II B. Without antennae and with four pairs of legs, although the maxillary palpi are often leg-like in form, making the animal appear to have five pairs of legs. p. 12 ARACHNIDA. BB. With antennae. C. With more than three pairs of legs ; and without wings, p. 45 M YRIAPODA. CC. With only three pairs of legs, and usually with wings in the adult state, p.48 HEXAPODA. Class CRUSTACEA (Crus-ta'ce-a). The Crustaceans (Crus-ta1 ce-ans). The members of this class are aquatic Arthropoda, which breathe by true gills. They have two pairs of antenna and at l$ast five pairs of legs. The most familiar illustrations of the Crustacea are the Cray-fishes, the Lobsters, the Shrimps, and the Crabs. Cray-fishes (Fig. 3) abound in our brooks, and are often improperly called Crabs. The Lobsters, the Shrimps, and the true Crabs live in salt water. The Crustaceans are distinguished from all oth- er Arthropods by their mode of respiration, being the only ones that breathe by true gills. Many in- sects live in water, and are furnished with gill-like FIG. 3.-A Cray-£sh. organs; but these are tracheal gills, organs which differ essentially in structure from true gills, as described later, in the chapter on Anat- omy of Insects. The Crustacea also differ from other Arthropoda in having two pairs of antennae; and from all 12 THE STUDY OF INSECTS. except the Myriapoda in having many (more than four) pairs of legs. The illustrations named above are the more conspicuous members of the class ; but many other smaller forms abound both in the sea and in fresh water. Some of" the more minute fresh-water forms are almost sure to occur in any fresh- FIG. 4.— Crustacea : a. Cypris; 6, . Cyclops; c.Daphnia. water aquarium. In Figure 4 are represented three of these, greatly enlarged. Among the Crustacea that live in damp places on land the Sow-bugs, Oniscidce (O-nis'ci-dae), are most often- seen. These frequently occur about water-soaked wood ; and are often mistaken, by students begin- ning the study of Entomology, for insects or Myria- pods. Figure 5 represents a Sow-bug. On the sea-coast an immense number of forms of Crustacea occur. Class ARACHNIDA (A-rach'ni-da). Scorpions, Harvestmen, Spiders, Mites, and others. The members of this class are air-breathing Arthropods, in which the head and thorax are grown together, forming a cephalothorax, which have four pairs of legs jit ted for walk- ing, and which have no antennce. The Arachnida abound wherever insects occur, and are often mistaken for insects. But they can be easily distin- guished by the characters given above, even in those cases where an exception occurs to some one of them. The more important of the exceptions are the following : In the Sol- pugida the head is distinct from the thorax ; as a rule the young of mites have only six legs, but a fourth pair are added during growth ; and in the gall mites (Phytoptus) there are only four legs. In the Arachnida we find only simple eyes. The cephalothorax (ceph-a-lo-tho'rax) bears six pairs of INSECTS AND THEIR NEAR RELATIVES. FIG. 6.— Lower side of cephalothorax of a spider : md, man- dible: >«.r, maxilla; />, palpus ; /, lower lip ; s, sternum. appendages— two pairs of jaws, and four pairs of legs. The first pair of jaws are the mandibles (man'di-bles), the second, the maxilla (max-il'lae). The mandibles (Fig. 6, md) lie in front of and above the mouth, and consist each of two or three segments. They serve for seizing prey, and often also for killing it. In many books they are termed the chelicerce (che-lic'e-rae). The maxillce(¥'\g. 6, mx] lie just behind the mandibles, one on each side of the mouth. Each maxilla bears a large feeler or palpus (Fig. 6, /). These palpi vary greatly in form ; frequently they resemble legs ; hence many Arachnida appear to have five pairs of legs. The palpi are often so largely developed that each maxilla ap- pears to be merely the first segment of its leg-like palpus. These appendages are often called the pedipalpi (ped-i-pal'pi). But as the name Pedipalpi is applied to one of the or- ders of the Arachnida, we will call these ap- pendages the palpi. The legs of Arachnida consist typically of seven parts (Fig. 7), which are named, begin- ning with the one next to the body, as fol- lows : i, coxa (cox'a) ; 2, trochanter (tro-chan'- ter); 3, femur (fe'mur); ^patella (pa-tel'la); 5, tibia (tib'i-a) ; 6, metatarsus (met-a-tar'sus) ; and 7, tarsus (tar'sus). The tarsus may be composed of several segments, and is usually furnished with claws. Two forms of breathing organs are found in this class : one, tracheae, resembling the tracheae of insects, described in the chapter on the anatomy of insects ; and the other, tracheal lungs or lung sacs, which consist of many leaf-like plates enclosed in a sac. Both forms open by paired spira- cles, which are usually situated on the lower side of some of the abdominal segments. FIG. 14 THE STUDY OF INSECTS. Very great differences exist in the several orders of the Arachnida in respect to the division of the body into seg- ments. In arranging the orders in a series, we place first those in which the segments of the body are most distinctly indicated, while those which seem to depart more widely from the segmented type characteristic of the Arthropoda are placed later. The class Arachnida includes seven orders ; these are designated as follows : The Scorpions, Order SCORPIONIDA (p. 15). The Jointed Spiders, Order SOLPUGIDA (p. 16). The Pseudoscorpions, Order PSEUDOSCORPIONES (p. 17). The Whip-scorpions, Order PEDIPALPI (p. 17). The Harvestmen, Order PHALANGIDEA (p. 19). The Spiders, Order ARANEIDA (p. 20). The Mites, Order ACARINA (p. 42). TABLE OF THE ORDERS OF THE ARACHNIDA. A. Abdomen distinctly segmented. B. Abdomen with a tail-like prolongation. C. Tail stout and armed with a sting at the end ; first pair of legs not greatly elongated ; a pair of comb-like appendages on the lower side of the second abdominal segment in the adult. (Scorpions?) p. 1 5 SCORPIONIDA. CC. Tail slender, whip-lash-like, without sting; first pair of legs much longer than the others ; without comb-like appendages on abdomen. {Whip-scorpions) (Thelyphonidce.) p. 17. PEDIPALPI. BB. Abdomen without a tail-like prolongation. C. Palpi with pincer-like claws. (Pseudoscorpions.) p. 17. PSEUDOSCORPIONES. CC. Palpi without pincer-like claws. D. Abdomen joined to the thorax by a slender stalk; front legs greatly elongated and with whip-lash-like tarsi. ( Whip- scorpions^ (Phrynidce) p. 17 PEDIPALPI. DD. Abdomen broadly joined to the thorax. E. Legs usually very long and slender; thorax not dis- tinctly divided into three segments. (Harvestmen) p. 19. PHALANGIDEA. EE. Legs moderately long ; head distinct from thorax ; thorax distinctly divided into three segments, p. 16. SOLPUGIDA. INSECTS AND THEIR NEAR RELATIVES. AA. Abdomen unsegmented. B. Abdomen joined to the cephalothorax by a short, narrow stalk. (Sptders.) p. 20 ARANEIDA. BB. Abdomen fused with the cephalothorax. (Mites.) p. 42. ACARINA. Order SCORPIONIDA (Scor-pi-on'i-da). The Scorpions. With the scorpions (Fig. 8), the body is divided into a compact, unsegmented cephalothorax, and along, segmented abdomen. The abdomen is divided into two portions : a broad pre-abdo- men, consisting of seven segments ; and a slenderer tail-like division, the post-abdomen, consisting of five seg- ments. At the end of the post-abdo- men there is a large poison-sting, which appears like a segment. The mandibles and the palpi are provided with pincers. As the palpi are very large, with stout pincers, they resem- ble in a striking manner the great claws of lobsters. The cephalothorax bears from three to six pairs of eyes. Scor- pions breathe by means of lung sacs, of which there are four pairs, opening on the lower side of the third to the sixth abdominal segments. Full-grown scorpions possess a pair of comb-like organs on the lower side of the second abdominal segment. The function of these organs is not yet known. The sexes of scorpions differ in that the male has broader pincers and a longer post-abdomen. Scorpions do not lay eggs, the young being developed within the mother. After the birth of the young, the mother apparently shows great regard for them, carrying them about with her for FIG. 8. — A Scorpion. i6 THE STUDY OF INSECTS. some time, attached by their pincers to all portions of her body. Scorpions live in warm countries. They are common in the southern portion of the United States, but are not found in the North. They are nocturnal, remaining concealed dur- ing the day, but leaving their hiding-places at dusk. When they run the post-abdomen is bent upwards over the back. They feed upon spiders and large insects, which they seize with the large pincers of their palpi, and sting to death with their caudal poison sting. The sting of a scorpion rarely if ever proves fatal to man, although the larger species, which occur in the Tropics, pro- duce serious wounds. Nearly twenty species are known from North America. Order SOLPUGIDA (Sol-pu'gi-da). The Jointed Spiders. The members of this order differ from all other Arach- nida in having the head separate from the thorax, and in having the thorax composed of three distinct segments, as with insects. The mandibles are very large, and are furnished with strong pincers. The palpi are shaped like the legs, and are said to be used in locomotion. The first of the four pairs of true legs, like the palpi, are not furnished with claws, and are used as palpi. There are only two eyes. Respi- ration is effected by means of tracheae, which open through three FIG. 9. — A Jointed-spider, Datames diiatata. (After Putnam.) pairs of spiracles, situated in the first thoracic and the second and third abdominal segments. Only a few species of Solpugida occur in the United States, and specimens of these are rarely found. So far INSECTS AND THEIR NEAR RELATIVES. I? as is known, our species are nocturnal, remaining con- cealed during the day. They prey upon small insects, and are believed to be harmless. Figure 9 will serve to show the appearance of these curious animals. The popular name, jointed-spiders, is suggested by the segmented con- dition of the abdomen. Order PSEUDOSCORPIONES (Pseu-do-scor-pi'o-nes.) The Pseudoscorpions. The pseudoscorpions (Fig. 10) are small Arachnida, which resemble scorpions in the form of their body, except that the hinder part of the abdomen is not nar- row, as is the post-abdomen of scorpions, and they have no caudal poison-sting. The abdo- men is broad, flat, and composed of eleven segments, or in some cases of only ten. The pseudoscorpions possess only one or two pairs of eyes, and in some, eyes are want- ,-r., , , , i FIG. 10. — A Pseu- ing. They breathe by means of tracheae, doscorpion. which open through two pairs of spiracles on the lower side of the second and third abdominal segments. These little scorpion-like creatures live under stones, be- neath the bark of trees, in moss, and in the dwellings of man, between the leaves of books, etc. They run rapidly, side- wise and backwards ; and feed on mites and small insects. They are often found attached to insects, especially to flies; but they probably do not feed on these large insects, but merely use them as means of rapid locomotion. The pseudoscorpions occur in the Northern States as well in the South. Order PEDIPALPI (Ped-i-parpi). The Whip-scorpions. These strange creatures are found only in the extreme southern part of our country, being tropical animals. In 18 THE STUDY OF I If SECTS. their general form they have some resemblance to scor- pions. They can be easily distinguished by the form of the front legs, which are greatly elongated, and have the tarsi broken up into many small segments; this gives these legs a more or less whip-lash-like appearance. In one family the abdomen also bears a whip-lash-like appendage. The mandibles are furnished with claws ; the palpi are very large and armed with strong spines, and the abdomen is distinctly separated from the thorax. The order includes two families, both of which are represented in the United States. Family THELYPHONID^E (Thel-y-phon'i-dae). The Tailed Whip-scorpions. This family is represented in the United States by only a single species, the Giant Whip - scorpion, TJielyphonus giganteus (The-lyph'o-nus gi-gan- te'us). This species measures when full grown from four to five inches in length. Figure 1 1 represents one less than natural size. These whip-scorpions are great- ly feared on account of their supposed venomous powers, but it is prob- able that there is no foundation for this fear. Although it has been stated often that their bites are poisonous, we can find no direct evi- FlG. \\.-Thelyphc fCiganteus. INSECTS AND THEIR NEAR RELATIVES. dence that it is so. with their palpi. They destroy their prey by crushing it Family PHRYNID^: (Phryn'i-dae). The Tailless Whip-scorpions. This family is represented in our fauna by the genus Phrynus (Phry'nus), the members of which are smaller than the Giant Whip-scorpion. In this family the front legs are even more whip-lash-like than in the preceding family ; the whole body is relatively shorter and broader; the abdomen is joined to the thorax by a slender stalk, and the tail-like appendage is lacking. Order PHALANGIDEA (Phal-an-gid'e-a). The Harvestmen, or Daddy Long Legs. The Harvestmen are very common in most parts of the United States. They are well known to children in this country under the name Daddy Long Legs, but as this name is also sometimes applied to Crane-flies, Harvestmen is preferable. In some sections of the country the Har- vestmen are known as Grandfather Graybeards. Most Harvestmen can be recognized by their very long and slender legs (Fig. 12), although some species have FIG. 12. — The Striped Harvestman. comparatively short ones. The cephalothorax is indistinctly if at all segmented. The abdomen is short, broad, consists 2O THE STUD Y OF INSECTS. of six segments, and is without a tail-like appendage ; it is broadly joined to the cephalothorax. The eyes of the Harvestmen a're two in number, and are situated on a prominent tubercle near the middle of the cephalothorax. The mandibles are pincer-like. The maxillae are large, and so opposed as to act as jaws ; their palpi are four-jointed, and are small compared with the palpi of the preceding orders; they resemble in form and func- tion the palpi of insects. The members of this order breathe by tracheae, which open by a single pair of spir- acles, on the lower side of the body at the junction of the cephalothorax and abdomen. The Harvestmen feed on small insects, especially Aphids, and are perfectly harmless. They are said to devour their prey, chewing it with their maxillae, and swallowing it, instead of merely sucking out the blood, as do most other Arachnida. Although the Harvestmen have stilt-like legs, they do not raise the body much above the ground when they walk, but carry it quite near their feet, with the middle part of their legs high in the air. They are said to pounce upon their prey as does a cat upon a mouse, and seize it with their palpi as if with hands. It is a common practice with children to catch these creatures and say to them, " Grandfather Graybeard, tell me where the cows are, or I'll kill you." As the poor frightened animal points its legs in all directions in its frantic efforts to escape, it usually earns its freedom ; but too often it is not without the loss of one or more legs. Order ARANEIDA (Ar-a-ne'i-da). The Spiders. The Spiders differ from other Arachnida in having the abdomen unsegmented and joined to the cephalothorax by a short, narrow stalk. The cephalothorax is also un- INSECTS AND THEIR NEAR RELATIVES. 21 segmented ; and the abdomen bears at its end organs for spinning silk (Fig. 13). FIG. i^.—Pencetta viridans. (From the Author's Report on Cotton Insects.) The mandibles (Fig. 14, met) consist of two segments, a strong basal one and a claw-shaped terminal one, at the tip of which a poison gland opens (Fig. 15). It is by means of these organs that spiders kill their prey. The palpi are leg- like in form, but differ greatly according to sex. In the female the last segment of the palpus resembles a foot of the spider, and is usually armed with a well-developed curved claw. But in the male the corre- sponding segment is more or less enlarged, and very complicated in structure (Fig. 16). Fl0Gf- The greater number of spiders have four Si pairs of eyes (Fig. 17), but there may be f FIG. 15.— Tip of claw of FIG. 16.— Maxilla and FIG. 17.— Head of spider, mandible of spider. palpus of male house- showing eyes and mandi- spider. bles. 22 THE STUDY OF INSECTS. only one, two, or three pairs ; and certain cave spiders are blind. Spiders breathe by means of lung-sacs, of which there are one or two pairs ; and some have tracheae also. The lung-sacs open on the lower side of the abdomen near its base, and between them is the opening of the reproductive organs. The tracheae open through a single spiracle near the hind end of the body, just in front of the spinning organs. The spinning organs, which are situated near the end of the abdomen, consist of two or three pairs of spinnerets. These appendages (Fig. 18) are more or less finger-like in form, and some- times jointed. Upon the end of each spinneret there are many small tubes, the spinning tubes, from which the silk FK;. ,8.-End of abdomen of ™ spun (Fig- 19)- Some spiders have as many as one hundred and fifty or two hundred of these spinning-tubes on each spinneret. The silk is in a fluid state while it is within the body, but it hardens as soon as it comes in contact with the air. Ordinarily the tips of the spinnerets are brought close together, so that all the minute threads that emerge from the numerous spinning tubes unite to form a single thread. This, however, may be so delicate as to be invisible, except in a favorable light. Sometimes a spider will spread its spinnerets apart, and thus FlG. ,9. spin a broad ribbon-like band. We have observed ^ ?™¥P of a spider seize a large grasshopper which was en- tue^'- tangled in its web, and, rolling it over two or three enlar&ed- times, completely envelop it in a sheet of silk spun from its spread-apart spinnerets. In the construction of their web some spiders make use of two kinds of silk. One of these is dry and inelastic ; the other, viscid and elastic. This fact can be easily seen by examining an orb-web. If the spiral line which forms INSECTS AND THEIR NEAR RELATIVES. 23 the greater part of the web be touched, it will adhere to the finger, and will stretch, when the finger is withdrawn, to several times the original length. But if one of the radiat- ing lines or a portion of the outer framework be touched, it will neither adhere to the finger nor be stretched. If the spiral line be examined with a lens, it will be found to bear numerous bead-like masses of viscid matter (Fig. 20); this explains its adhesiveness. It is supposed that the two kinds of silk are spun from different spinnerets, and that the yiscid silk comes from the front pair. When this silk is first spun the viscid matter forms a continuous layer of liquid on the outside of it. But very soon this layer breaks up into the bead-like masses — in a way similar to that in which the moisture on a clothes-line in a foggy day collects into drops. Spiders of the two families Dictynidcz and Uloboridce have spinning organs differing from those of all other FIG. 2o.-Viscid silk from an orbweb. FIG. 2i.— Spinnerets of a Dictynid spider. The middle pair of spinnerets are con- cealed by the first pair, c, cribellum. FIG. 22.— Last two segments of hind leg of spider, show- ing calamistrum. spiders. They have in front of the usual spinnerets an additional organ, which is named the cribellum (cri-bel'lum) (Fig. 21). This bears spinning-tubes like the other spinner- ets, but these tubes are much finer. These spiders have also on the metatarsus of the hind legs one or two rows of curved spines : this organ is the calamistrum (cal-a-mis'trum) (Fig. 22). By means of the calamistrum these spiders comb from the cribellum a band of loose threads, which form a part of their webs. THE STUD Y OF INSECTS. Spiders make use of silk in the construction of their webs or snares, in the building of tubes or tents within which they live, in the formation of egg-sacs, and in loco- motion. Fig. 23 represents the large egg-sac of one of the orb- weavers. This is made in the autumn, and contains at that season a large number of eggs — five hun- dred or more. These eggs hatch early in the winter ; but no spiders emerge from the egg-sac until the following spring. If egg-sacs of this kind be opened at differ- ent times during the winter, as was done by Dr. Wilder, the spiders will be found to increase in size but diminish in num- ber as the season advances. In fact, a strange tragedy goes on within these egg-sacs: the stronger spiders calmly devour their weaker brothers, and in the spring those which survive emerge sufficiently nourished to fight their bat- tles in the outside world. The egg-sacs of the different species of spiders vary FIG. 23.— Egg-sac of A rgiope riparia. (From Wilder.) FIG. 24.— Egg-sac of Nepliila, plumipes. (From Wilder.) greatly in form. In some, as in that figured above, the outer covering is very dense, while in others the outer part con- JWSECTS AND THEIR NEAR RELATIVES. 2$ sists of loose flossy silk (Fig. 24). One of the most common kinds is very flat, silvery in color, and is firmly attached to stones lying upon the ground (Fig. 25). Every one knows that a spider wishing to descend to some place beneath it simply fastens a line to the object which it is upon and then drops boldly off, regulat- FlG 25._Eg?.sac of a ing the rate of its descent by spinning the line rapidly or slowly; when the spider wishes to return, it has only to climb up the same line. Frequently spiders pass from point to point in a hori- zontal direction by means of silken bridges. These are formed in this way : The spider spins out a thread, which is carried off by a current in the air. After a time the thread strikes some object and adheres to it ; then the spider pulls the line tight, and fastens it where it is standing. It then has a bridge, along which it can easily run. But more remarkable than either of these uses of silk for locomotion is the fact that many spiders are able to travel long distances, hundreds of miles, through the air by means of these silken threads — "sailing mid the golden air In skiffs of yielding gossamere." — {Hogg.) The Aeronautic Spiders, or Flying Spiders, as they are more commonly called, are frequently very abundant, espe- cially in warm antumn days. At such times innumerable threads can be seen streaming from fences, from bushes, and the tips of stalks of grass, or floating through the air. The flying spider climbs to some elevated point, which may be merely the tip of a stalk of grass, and then, standing on the tips of its feet, lifts its body as high as it can, and spins out a thread of silk. This thread is carried up and away by a current of air. When the thread is long enough the force of the air current on it is sufficient to buoy the spider up. It 26 THE STUDY OF INSECTS. then lets go its hold with its feet and sails away. That these spiders travel long distances in this manner has been shown by the fact that they have been seen floating through the air at sea far from land. Representatives of nearly thirty families of spiders have been found in the United States. But some of these fami- lies include only rare species, and others are represented by so few species that we cannot discuss them here. The greater number of our spiders belong to the eleven families described below. The following table will aid the student in separating these families. TABLE FOR SEPARATING THE PRINCIPAL FAMILIES OF SPIDERS. A. Claw of the mandibles moving vertically; four lung-slits present. { Tarantulas?) p. 27 THERAPHOSIM:. AA. Claw of the mandibles moving horizontally; only two lung-slits present, but with a single spiracle or a pair of spiracles also. B. Eyes equal or nearly equal in size, and usually arranged in two rows. C. Feet furnished with two claws (Fig. 28). Spiders which do not spin webs for catching prey. D. Second pair of legs not so long as the fourth pair. E. Maxillae with a concavity or furrow (Fig. 29). Spiders which live on the ground., p. 29 DRASSID.* EE. Maxillae convex (Fig. 32). Spiders which live chiefly in silken tubes on bushes, p. 30 CLUBIONID/E. DD. Second pair of legs as long as or longer than the fourth pair. ( The crab-spiders.} p. 40 THOMISIDJE. CC. Feet furnished with three claws (Fig. 38). Spiders which spin webs for catching prey. D. The caudal pair of spinnerets very long, and two-jointed. Spiders which make irregular webs with a tube or hiding- place at one side, from which they run on the upper surface of the web, to catch their prey. p. 30 AGALENID/E. DD. All of the spinnerets short. E. With cribellum and calamistrum. Spiders making webs in which there are curled threads, or double threads. INSECTS AND THEIR NEAR RELATIVES. 2? F. The side eyes not as far apart as the middle eyes; a considerable space between the eyes and the front edge of the head. Spiders making irregular webs. p. 32. DICTYNID^;. FF. The side eyes as far or farther apart than the middle eyes; eyes very close to the front edge of the head. Spiders making regular webs. (Uloborus) p. 38. ULOBORID;E. EE. With neither cribellum nor calamistrum. Spiders mak- ing webs in which there are no curled threads. F. Eyes not near the front edge of the head, the space be- tween the two being greater than that occupied by the eyes (Fig. 37). Spiders that spin irregular webs, in or near which they live, hanging back downwards, p. 34. THERIDIID/E. FF. Eyes near the front edge of the head, the space be- tween the two being less than that occupied by the eyes (Fig. 42). Spiders that make regular webs, consisting chiefly of lines radiating from the centre, and a spiral or looped sticky line. p. 35 . . . EPEIRID.-E. BB. The eyes unequal in size and arranged in three or four rows. C. With cribellum and calamistrum. Spiders which make webs. (Hyptiotes.) p. 38 ULOBORID^E. CC. With neither cribellum nor calamistrum. Spiders which do not spin webs for catching prey. D. The largest eyes not in the front row. (Running spiders.) p. 40 LYCOSID^E. DD. The largest eyes in the front row. (Jumping spiders) p. 42 ATTID^E. Family THERAPHOSID^: (Ther-a-phos'i-dae). The Tarantulas and the Trap-door Spiders. Those who live in the warmer parts of our country know well the large spiders commonly called Tarantulas. These are the giants among spiders, some of them being the largest known ; but some species of this family are not very large. They are dark-colored, hairy spielers, and can be distinguished from the other families mentioned here by the fact that the 28 THE STUDY OF INSECTS. claw of the mandibles works up and down instead of side- wise. The members of this family do not construct true webs, but they dig long tubes in the earth, which they line with silk, or line their hiding-places in clefts in trees or elsewhere with a layer of silk. They live only in warm countries. One of the best known of the Tarantulas is Eurypelma_ hcntzii (Eu-ryp'el-ma hentz'i-i). This species occurs in the South and in the Middle West, and is the largest of our spiders (Fig. 26). Several closely allied species are found in California. FIG. 26.— A Tarantula, Eurypelnta hentzii. But the members of this family that have attracted most admiration on account of their habits are the Trap-door Spiders. These dig a tube in the ground, as do many other members of this family ; but this tube is lined with a denser FIG. 27. — Entrance to nest of a trap-door spider. layer of silk, and is provided with a hinged lid, which fits the opening of the tube with wonderful accuracy (Fig. 27). INSECTS AND THEIR NEAR RELATIVES. 29 The spider hides in this nest when not seeking its prey. Some species take the precaution to build a branch to their nest, and to provide this branch with a door. As this door forms a part of one side of the main tube, it is not likely to be observed by any creature which may find its way past the first door of the nest. Several species of Trap-door Spiders occur in the South- ern and Southwestern States. Family DRASSID^: (Dras'si-dae). The Drassids, or Tube Weavers in part. There are certain dark-colored spiders that spin no web, but wander about at night in search of prey, and hide under leaves and stones during the day-time. Many of them make silken tubes, in which they hide in winter or while moulting or laying eggs. Hence they have been termed Tube Weavers, a name which is also applied to certain other spiders. We will therefore call the members of this family the Drassids (Dras'sids). In this family the body is long, and is usually flattened above. It is carried near the ground in walking. The legs are rather short and stout ; the second pair are not longer than the fourth, and the feet are furnished with only two claws (Fig. 28). The eyes are in two nearly straight rows, and the maxillae are concave or fur- nished with a furrow (Fig. 29). One of the most common FIG 28 —Foot of species in the aDnissid- East is Drassus saccatus (Dras'sus sac-ca'tus) (Fig. 30). It lives under stones, in a large bag of silk, in which the FIG. 29.— Maxilla of a Drassid. FIG. 30.— Drassus saccatus. 3O THE STUDY OF INSECTS. female stays with her egg-sac. In early summer a male and female live together in the nest. Family CLUBIONID.E (Clu-bi-on'i-dae). The Clubionids, or Tube Weavers in part. There may be found during summer, in flat tubular nests on plants, usually in rolled leaves, spiders that spin no webs to entrap their prey. These spiders very closely re- semble the Drassids in structure, but are usually lighter in color, with the legs a little longer and more slender, and the abdomen more nearly cylindrical (Fig. 31). F.C. 3i.-cv.w- FIG. 32.-Maxiiia of They are also distinguished by the form of the maxillae, which are convex (Fig. 32). These spiders belong to the family Clubionidas. As we have no appropriate common name for these spiders, they may be called the Clubionids (Clu-bi- on'ids). During the winter the Clubionids hide under bark or stones, and make tubular nests in these places. Family AGALENID^E (Ag-a-len'i-dae). The Funnel-tveb Weavers. Even the most careml observers seldom realize what an immense number of spider-webs are spun upon the grass in the fields. But occasionally these webs are made visible in the early morning by the dew which has condensed upon them. At such times we may see the grass covered by an almost continuous carpet of silk. The greater number of the webs seen at such times are of the form which we term funnel-webs. They consist of a •concave sheet of silk, with a funnel-shaped tube at one side, INSECTS AND THEIR NEAR RELATIVES. and numerous lines extending in all directions to the sup- porting spears of grass (Fig. 33). The tube serves as a FIG. 33.— Web of Grass Spider, Agalen hiding-place for the owner of the web ; from this retreat the spider runs out on the upper surface of the web to seize any insect that alights upon it. The tubes open below, near the roots of the grass ; so that the spider can escape from it if a too formidable insect comes upon the web. The funnel-web weavers (family Agalenidce) are long- legged, brown spiders, in which the head part of the cephalo- thorax is higher than the thoracic part, and distinctly separated from it by grooves or marks at the sides. The eyes are usually in two rows, but in Agalena the middle eyes of both rows are much higher than the others. The feet have three claws. The posterior pair FIG. 34. — Agalena. ntevia. 32 THE STUDY OF INSECTS. of spinnerets are two-jointed, and usually longer than the others. The common grass spider, which abounds in all parts of the United States, is Agalena ncevia (Ag-a-le'na nas'vi-a (Fig. 34> Family DlCTYNHLE (Dic-tyn'i-dae). The Curled-tJiread Weavers witJi Irregular Webs. The Dictynids (Dic-tyn'ids). Certain spiders are remarkable for using two kinds of silk in the formation of their webs. Thus, as explained later, the Orb Weavers build the framework of their orbs of dry and inelastic threads, and attach to this framework a thread which is sticky and elastic ; while most spiders which make irregular webs use only one kind of silk. There are, however, certain species of irregular web-weavers which use two kinds of silk. One of these is a plain thread like that spun by other spiders, and the other is a peculiar curled thread or a delicate band of tissue in which there are curled threads. The curled-thread weavers represent two families, one of which makes irregular webs; the other, those which are of definite form. The first of these is the Dictynidce. The curled -thread or tissue-like band is made in the same way by both families. It is composed of silk spun from a special spinning-organ, situated in front of the ordinary spinnerets, and named the cribellum (cri-bel'lum) ; and is combed into its peculiar form by means of a comb of stiff hairs, the calamistrum (cal-a-mis'trum), which is borne by the metatarsus of the hind legs (see page 23). In mak- ing the curled thread the spider turns one of its hind legs under the abdomen so that the calamistrum is just under the cribellum, and the foot rests on the other hind leg. It then moves its hind legs back and forth rapidly, so that the calamistrum combs out from the spinning-tubes, and at the same time tangles, a band of fine threads. INSECTS AND THEIR NEAR RELATIVES, 33 This band of tangled or curled threads is easily seen in the webs of these spiders, being wider than the ordinary threads and white in color. In old webs it becomes conspicuous by the large amount of dust which it collects. Figure 35 shows the appearance of this band when magnified, and the way in which it is attached to the plain threads. Our more common Dictynids make webs of various shapes, on fences, under stones, in holes in rotten logs, and FIG. 35.— Curled thread of a Dictynid, en- larged. FIG. 36.— Web of a Dictynid, on a dead branch of Ceanothus, somewhat enlarged. on plants. These webs are especially common among the flowers of Golden-rod and other plants having clusters of 34 THE STUDY OF INSECTS. small flowers (Fig. 36), and exhibit a slight degree of regularity. Family THERIDIID^: (Ther-i-di'i-dae). The Cobweb Weavers. Many are the kinds of webs spun by different spiders. Some of them, as the orb-webs and the funnel-webs, delight us with their wonderful regularity of form ; while others appear to be a mere shapeless maze of threads. Such are the structures whose presence in the corners of our rooms torment thrifty housewives, and which are disrespectfully termed cobwebs. The cobweb weavers (Family TJieridiidce) are small spiders with unusually slim legs. The space between the eyes and the front edge of the head is greater than the FIG. 37.— Face of FIG. 38.— Foot of spider FIG. y^.—Mimetus house spider. Wlth three claws. interfector. region occupied by the eyes (Fig. 37); the eyes are in two rows; and the feet are furnished with three claws (Fig. 38), This family includes many species, being in fact the largest of all of the families of spiders. Figure 39 represents a widely distributed species. Although the house spiders are the most familiar mem- bers of this family, the greater number of species spin their webs in the fields on bushes. These webs usually consist of a flat or curved sheet, under which the spider hangs back downward. This sheet is supported by threads running in all directions to the neighboring objects. Frequently there is a large number of these supporting threads above the web, which serve the additional purpose of impeding the flight of INSECTS AND THEIR NEAR RELATIVES. 35 insects, and causing them to fall into the web, where they are caught. Some of these spiders do not remain in their webs, but have a nest in a neighboring crack or corner, from which they rush to seize their prey. And sometimes there is a funnel-shaped tube leading to this nest. But-these spiders differ from the true funnel-web weavers in running back clown- wards on the lower side of their web. Family EPEIRID^: (E-pei'ri-dae). TJie Orb Weavers. Few if any of the structures built by lower animals are more wonderful than the nets of orb-weaving spiders, but these beautiful objects are so common that they are often considered hardly worthy of notice. If they occurred only in some remote corner of the earth, every one would read of them with interest. The nets of the different species of orb weavers differ in the details of their structure, but the general plan is quite similar. There is first a framework of supporting lines. The outer part of this framework is irregular, depending upon the position of the objects to which the net is attached; but the more central part is very regular, and consists of a number of lines radiating from the center of the net (Fig. 41). All of these supporting lines are dry and inelastic. But there is spun upon the radiating lines in a very regular manner a thread which is sticky and elastic (Fig. 20, p. 23). Usually this sticky thread is fastened to the radiating lines so as to form a spiral, but a few species make nets in which this thread is looped back and forth. Many of the orb weavers strengthen their nets by spin- ning a zigzag ribbon across the center. This ribbon is made by spreading the spinnerets apart so that the minute threads from the spinning tubes do not unite to make a single thread, as is usually the case. Some of the orb weavers live in their nets hanging head THE STUDY OF INSECTS. downwards, usually near the center of the net ; others have a retreat near one edge of the net, in which they hang back FIG. 41. — Partially completed web of Epeira. downwards. While resting in these retreats they keep hold of some of the lines leading from the net, so that they can instantly detect any jar caused by an entrapped insect. When an insect in its flight touches one of the turns of the sticky line, the line sticks to it ; but it stretches so as to allow the insect to become entangled in other turns of the line. If it were not for this elasticity of the sticky line, most insects could readily tear themselves away before the spider had time to reach them. In making its web an orb weaver first spins a number of lines extending irregularly in various directions about the place where its orb is to be. This is the outer supporting framework. Often the first line spun is a bridge between two quite distant points. This is done as described on p. Having a bridge across the place where the web is to be, it is an easy matter for the spider to stretch its other lines where it wishes them. In doing this it fastens a thread to one point, and then walks along to some other point, spin- INSECTS AND THEIR NEAR RELATIVES. 37 ningthe thread as it goes, and holding it clear of the object on which it is walking by means of one of its hind legs. When the second point is reached the thread is pulled tight and fastened in place. After making the outer framework the radiating lines are formed. A line is stretched across the space so as to pass through the point which is to be the center of the orb. In doing this the spider may start on one side, and be forced to walk in a very roundabout way on the outer framework to the opposite side. It carefully holds the new line up behind it as it goes along, so that it shall not become entangled with the lines on which it walks ; one or both hind feet serve as hands in these spinning operations. The spider then goes to the point where the centre of the orb is to be, and fast- ening another line there, it walk back to the outer frame- work, and attaches this line an inch or two from the first. In this way all of the radiating lines are drawn. The next step is to stay these radii by a spiral line which is begun at the center, and attached to each radius as it crosses it. The turns of this spiral are as far apart as the spider can con- veniently reach, except at the center of the web. All of the threads spun up to this stage in the construction of the web are dry and inelastic. The spider now proceeds to stretch upon this framework a sticky and elastic line, which is the most important part of the web, the other lines being merely a framework to support it. In spinning the sticky line the spider begins at the outer edge of the orb, and passing around it fastens this line to each radius as it goes. Thus a second spiral is made. The turns of this spiral are placed quite close together, and the first spiral, which is merely a temporary support, is destroyed as the second spiral pro- gresses. Figure 41 represents a web in which the second spiral is made over the outer half of the radii. In this fig- ure, aa represents the temporary stay-line ; bb, the sticky spiral ; and cc, the fragments of the first spiral hanging from the radii. THE STUD Y OF INSECTS. G. 43. — Foot of Epeira. The orb weavers (Family Epeiridce) are usually plump spiders, the abdomen being large, and often nearly spher- ical. The space between the eyes and front edge of the head is less than the region Epeira- occupied by the eyes (Fig. 42). The eyes are arranged in two rows. The front legs are longer than the others. The feet have three claws (Fig. 43), and the spinnerets are all short. In some species of this family the male is much smaller than the female. Family ULOBORID/E (U-lo-bor'i-dae). The Curled-thread Weavers with Regular Webs. The Uloborids (U-lo-bo'rids). We have already described the thread-curling habits of the Dictynids (p. 32), and the curious organs called cribel- lum and calamistrum (Fig. 44), by which these curled threads are made (p. 23). Similar organs and a similar habit are possessed by the spi- ders of the family Uloboridce. These spiders, however, make webs which are regular in form. There are only two genera belonging to this family in the United States ; but as the webs made by these are very different, we will de- scribe both. The Triangle Spider, Hyptiotes cavatus (Hyp-ti'o-tes ca- va'tus). — This spider is common all over New England and the Middle States, and has been found as far to the south- west as Texas. Its web is most often found stretched be- tween the twigs of a dead branch of pine or spruce. At first sight this web appears like a fragment of an orb web (Fig. 45); but a little study will show that it is complete. The accompanying figure, by Dr. Wilder, who first described FIG. 44.— Calamistrum of Hyptiotes. INSEC7^S AND THEIR NEAR RELATIVES. 39 the habits of this spider (see Popular Science Monthly, 1875), illustrates the form of the web. It consists of four plain lines corresponding to the radiating lines of an orb web, and a series of double cross lines, which are spun by the cribel- lum and calamistrum. From the point where the radiating lines meet a strong line extends to one of the supporting twigs. Near this twig the spider rests, pulling the web tight FIG. 45.— Web of Hyptiotes cavatus. (From Wilder.) so that there is some loose line between its legs, as shown in the enlarged figure. When an insect becomes entangled in one of the cross lines, the spider suddenly lets go the loose line so that the whole web springs forward, and the insect is entangled in other cross threads. The spider then draws the web tight and snaps it again. This may be repeated several times before the spider goes out upon the web after its prey. Uloborus (U-lob'o-rus). — The spiders of this genus make round webs which resemble at first sight those of the Orb Weavers ; but they differ from the ordinary orb webs in that 40 THE STUDY OF INSECTS. the spiral thread is made of curled or hackled silk. webs are nearly horizontal, and are usually made between stones or in low bushes. The spiders of this genus are not common, but they are widely distributed. They have not, however, been reported as yet from the Pacific coast. Family THOMISID^E (Tho-mis'i-dae). The Crab Spiders. There are certain spiders which are called crab spiders, on account of the short and broad form of the body, and the curious fact that they can walk more readily sidewise or backward than forward. These spiders spin no webs, but lie in wait for their prey. They live chiefly on plants and fences, and in the winter hide in cracks and under stones and bark. Most of the spe- cies are marked with gray and brown, like the bark upon which they live. Some species conceal themselves in flow- ers, where they lie in wait for their prey. These are brightly colored, like the flowers they inhabit ; so that insects visiting flowers may alight within reach of a spider before seeing it. In this -family the legs are turned outward and forward more than downward ; so that the body is carried close to the ground. The second pair of legs are as long as or longer than the fourth pair. The eyes are small, nearly equal in size, and ar- ranged in two rows. FlG. 46. — Misu- _ rill i r i • mena vatia. One of the best-known members of this family is the female of Misumenavatia (Mi-su'me-na va'ti-a). This is milk-white, with sometimes a light crimson mark on each side of the abdomen, and is found within flowers (Fig. 46). Family LYCOSID^: (Ly-cos'i-dae). The Running Spiders. Every collector of insects who has searched for speci- mens under stones and logs is familiar with the large, dark- colored, hairy spiders often found in these places. These INSECTS AND THEIR NEAR RELATIVES. 4! spiders frequently attract especial attention by dragging after them a large gray ball (Fig. 47) ; this is the egg-sac, which the female carries about with her attached to her spinnerets. These spiders run swiftly ; and as they depend FIG. 47. — Lycosa and egg-sac. on the use of their legs for the capture of their prey, they are well termed Running Spiders. These spiders resemble in general appearance and in habits the Tarantulas of the South and the West. But none of our species attain the great size of some of the Tarantulas, and in the Running Spiders the claw of the mandibles moves horizontally instead of vertically. In this family the body is hairy and usually much longer than broad. The eyes differ markedly in size, and are arranged in three or four rows. The larger eyes are not in the front row. The legs are rather long and quite stout. Like the Tarantulas, some of the Running Spiders build tubular nests in the ground, which they line with silk. Some- times the entrance to these nests is concealed by small sticks and leaves, and sometimes the spi- der builds a regular turret over the entrance of its tube (Fig. 48). These nests are used merely as retreats, the spiders wandering forth in search of their prey. The larger members of our common species belong to the FIG 48._Entrance to nest of Turret genus Aratfrt (Ly-co'sa). These sPider« ^«— «-**«. (After Marx.) drag after them their egg-sacs as described above ; and 42 THE STUDY OF INSECTS. when the young hatch they climb on their mother's back, and are carried about for a time. The females of the genus Dolomedes (Dol-o-me'des), which also belongs to this family, carry their egg-sac in their mandibles until the young are ready to hatch. At this time the mother fastens the egg- sac in a bush, and spins a web of irregular threads about it, among which the young spiders remain for a time. Family ATTlDyE (At'ti-dae). The Jumping Spiders. The Jumping Spiders are of medium size, with a short body and short stout legs (Fig. 49). They are common on plants, tlogs, fences, and the sides of buildings. They are very apt to attract attention by their pecul- iar appearance ; their short stout legs, bright colors, conspicuous eyes, and quick, jumping movements being very different from those of fc. ordinary spiders. The eyes are arranged in three or four rows; FLG«w/«r(F?om *ke front middle pair are the largest, and are Re orfonCk*8- verv conspicuous. These self-possessed spiders ton insects.) are able to stare an ordinary observer out of countenance. They move sidewise or backward with great ease, and can jump a long distance. They make no webs except nests in which they hide in winter or when moulting or laying eggs. In certain members of this family the body is longer than in the typical forms, and ant-like in appearance. Order ACARINA (Ac-a-ri'na). The Mites. In this order the abdomen is unsegmented and fused with the thorax, giving the entire body a more or less sac- like appearance. In many the body is marked by numerous INSECTS AND THEIR NEAR RELATIVES. 43 transverse, fine lines, which are so impressed as to appear like the divisions between minute segments (Fig. 52). The majority of mites are very small ; but some, as certain Ticks, are of considerable size. With the exception of a single family the members of which bring forth living young, all mites are produced from eggs. As a rule, the newly-hatched mites have only three pairs of legs; but a fourth pair are added during growth. In PhytoptiiSy which infests plants, there are only two pairs of legs. The mode of life of the different members of this order varies greatly : some are parasitic upon animals ; others infest living plants ; and many feed upon dead animal or vegetable matter, thus acting as scavengers. Among the mites that are parasitic upon animals are the various Ticks, which are very common in the warmer parts of our country. Figure 50 rep- resents the Cattle-tick of the Southern States. It should be remembered in this connection that the so-called Sheep-tick is a true insect, FIG. 5o. — The , . . , j j^.. Cattle-tick, fe- belonging to the order Diptera. male. The Itch-mite is a well-known parasite, infesting man and causing the disease known as the itch. The sensation character- istic of this disease is due to the burrowing of the mites in the skin ; and the efficiency of sulphur oint- FIG. 5i!-An itch-mite7 a^ from ment in checking this disease is beiow ; b, from above. due to the fact that by the use of it the mites are killed. Figure 51 represents an itch-mite greatly enlarged. Parasitic mites are frequently found attached to insects ; a common species occurs beneath the wings of locusts. The best known of the mites that infest plants is the one commonly called the Red Spider. This lives upon house- plants ; and in the warmer parts of the country, where there 44 THE STUDY OF INSECTS. is a dry season, it infests fruit-trees in the open air. As it thrives only in a dry atmosphere, it can be subdued upon house-plants by a liberal use of water. When it occurs upon plants in the open air it can be combated with any of the washes found useful in destroying scale insects. Some of the mites that infest plants produce galls. These galls are of various forms, but differ from those pro- duced by gall-flies (Family Cynipidce of the Order Hymen- opt era) in having open mouths, from which the young mites escape. A common disease of the pear, known as the pear-leaf blister, is produced by a four-legged mite, Pkytoptus pyri (Phy-top'tus py'ri) (Fig. 52). The blisters characteristic of FIG. ^.—Phytoptus pyri, greatly enlarged. the disease are swellings of the leaf, within which there is a cavity affording a residence for the mites. Figure 53 repre- g FIG. 53.— Diagram of gall of Phytoptus pyri : f, gall ; «, », normal structure of leaf ; a, open- ing of gall ; e, eggs. (After Soraur). sents a section of a leaf through one of these galls. Here the leaf is seen to be greatly thickened at the diseased part. On the lower side there is an opening through which the mite that started the gall entered, and from which young INSECTS AND THEIR NEAR RELATIVES. 45 mites developed in the gall can escape, in order to start new galls. In addition to the swelling of both surfaces of the leaf its Internal structure is seen to be modified. In some parts there is a great multiplication of the cells, and in others a large part of the cells have been destroyed. Two eggs of mites are represented in this gall. As the season advances, and the galls become dry and brownish or black, the thickening of the leaf becomes less marked. In fact, in some cases there is a shrinkage of the parts affected. Fig- FIG. 54.— Section of leaf showing structure of gall in autumn : g, &a'l I "> ni uninjured part of leaf ; a, opening of gall. ure 54 represents a section through a leaf collected and studied in October. Among the scavenger mites there are some that infest food products. Thus mites are sometimes found in cheese, in sugar, and in preserved meats. Class MVRIAPODA (Myr-i ap'o-da). The Centipedes and the Millipedes. The members of this class are air-breathing Arthropods, in which the head is distinct from the thorax, and the thorax and abdomen form a continuous region, with from six to two Jiundred segments, each bearing a pair of legs. The head bears a single pair of antenna. The thousand-legged worms, as they are commonly called, are well-known and generally feared creatures. But few students find them attractive subjects of study ; never- theless it is well to know something about them, for some of them are dangerous animals, and some are harmless. A few species are injurious to agriculture, while others are to be 46 THE STUDY OF INSECTS. classed among our friends. And all of them are of interest to the naturalist as representatives of a distinct type of Arthropods. If we omit certain small and rather uncommon forms, the Myriapods may be classed in two orders ; one consisting of the Centipedes, the other of the Millipedes. Order CHILOPODA (Chi-lop'o-da). The Centipedes. The centipedes can be recognized at a gjance by the fact that each segment of the body bears a single pair of legs (Fig. 55). The body is usually flattened, and the antennae are long and many- jointed. Many species of centi- FIG. 55-— A Centipede. pedes are venomous. The poison glands open through the claws of the first pair of legs, which are bent forward so as to act with the mouth parts. These creatures abound in all parts of the United States; those which are found in the North are comparatively small, and rarely, if ever, inflict serious injury to man ; but the larger species, which occur in the warmer regions, are said to be extremely venomous. The centipedes are predaceous, feeding on insects ; they usually live under stones, logs, and bark. There is one spe- cies, Cermatia forceps (Cer-ma'ti-a), which has very long legs, and only fifteen pairs of them, which is often found running on the walls of houses, especially in the Southern States. We have never heard of this centipede biting a human be- ing, and as it feeds upon insects, especially cockroaches, it: may be regarded as a welcome visitor in houses. INSECTS AND THEIR NEAR RELATIVES. 47 Order CHILOGNATHA (Chi-log'na-tha). The Millipedes. The millipedes differ from the centipedes in having two pairs of legs on each of the body segments except the first three. The body in most of them is not flattened as with the centipedes, and the antennae are comparatively short and few jointed (Fig. 56). FIG. 56.— A Millipede. The millipedes, as a rule, live in damp places and feed on decaying vegetable matter. They are harmless, except that occasionally they feed upon growing plants. CHAPTER III. Class HEXAPODA (Hex-ap'o-da). The Insects. The members of this class are air-breathing Arthropoau, with distinct head, thorax, and abdomen. They have one pair of antenna, three pairs of legs, and usually one or tivo pairs of wings in the adult state. There are about us on every side myriads of tiny crea- tures that are commonly passed unnoticed, and even when observed, they are usually thought to be unworthy of serious consideration. But all life is linked together in such a way that no part of the chain is unimportant. Frequently upon the action of some of these minute beings depends the mate- rial success or failure of a great commonwealth. The intro- duction and spread of a single species of insect (the Cot- tony-cushion Scale) in California threatened the destruction of the extensive orchards of that State ; thousands of trees perished. The introduction of a few individuals of a partic- ular kind of Lady-bug (Vedalia cardinalis), which feeds upon this pest and multiplies rapidly, soon checked the evil, and has nearly removed the pest from the State. But insects are of interest to us for other reasons than the influence they may have upon our material welfare ; the study of them is a fruitful field for intellectual growth. It is not a small matter to be able to view intelligently the facts presented by the insect world, to know something of what is going on around us. And so rich is this field that no one gains more than a mere smattering concerning it. HEXAPODA. 49 We know as yet comparatively little about the minute structure of insects ; the transformations and habits of the greater number of species have not been studied; and the blood-relationship of the various groups of insects is very imperfectly understood. If, therefore, one would learn something of the action of the laws that govern the life and development of organized beings, and at the same time ex- perience the pleasure derived from original investigation, he cannot find a better field than is offered by the study of in- sects. But it is not necessary that one should have the tastes and leisure required for careful scientific investigation in order to profit by this study. It can be made a recreation, a source of entertainment when we are tired, a pleasant oc- cupation for our thoughts when we walk. Any one can find out something new regarding insect architecture — the ways in which these creatures build nests for themselves or fo; their young. It is easy to observe remarkable feats of en- gineering, examples of foresight, wonderful industry, unre- mitting care of young, tragedies, and even war and slavery. The abundance of insects makes it easy to study them. They can be found wherever man can live, and at all seasons. This abundance is even greater than is commonly supposed. The number of individuals in a single species is beyond com- putation : who can count the aphids or the scale-bugs in a single orchard, or the bees in a single meadow? Not only are insects numerous when we regard individ- uals, but the number of species is far greater than that of all other animals taken together. The number of species in a single family is greater in several cases than the number of stars visible in a clear night. The word insect is often applied incorrectly to any mi- nute animal ; and even among naturalists there is some lack of uniformity in its use. Some writers include under this term the Arachnida and Myriapoda, as well as the Six-footed Insects. But the great majority of entomologists restrict 50 THE STUDY OF INSECTS. the term to the Hexapoda, and it is in this sense that we use it. The name Hexapoda is from two Greek words: Jiex, six ; and/w/r.y, foot. It refers to the fact that the members of this order differ from other Arthropods in the possession of only six feet. Insects breath by means of a system of air-tubes (tra- cheae) which extends through the body. This is true even in the case of those that live in water'and are supplied with gill-like organs (the tracheal gills ; see p. 75). The head is distinct from the thorax, and bears a single pair of antennae ; in these respects they are closely allied to the Myriapods. But they can be easily distinguished by the number of their feet, and, usually, also by the presence of wings. THE METAMORPHOSES OF INSECTS. Nearly all insects in the course of their lives undergo re- markable changes in form. Thus the butterfly, which de- lights us with its airy flight, was at one time a caterpillar; the bee, which goes so busily from flower to flower, lived first the life of a clumsy, footless grub ; and the graceful fly was developed from a maggot. In the following pages considerable attention will be given to descriptions of the changes through which various insects pass. It is our wish in this place merely to define certain terms which are used in describing these changes. Development without Metamorphosis. — In one of the orders of insects, the Thysanura, the young insect just hatched from the egg is of the same form as the adult insect. These insects merely grow larger, without any more marked change in form than takes place in our own bodies during our life. They are said, therefore, to develop without metamorphosis. Incomplete Metamorphosis. — There are many insects which undergo a striking change of form during their life, although the young greatly resembles the adult. Thus a young locust just out from the egg can be easily recognized as a locust. HEXAPODA. It is of course much smaller than the adult, and is not fur- nished with wings. Still the form of the body is essentially the same as that of the adult (Fig. 57). (The hair-line above the figure indicates the natural size of the insect.) After a time rudimentary wings appear; and these increase FIG. 5.7.— Nymph of Melanoflus, first stage. (After Einerton.) FIG. 58.— Nymph of Melanoplus, second stage. (After Emerton.) FIG. 59. — Nymph of Melanof>lus^ third stage. (After Emerton.) IG. 60. — Nymph of Melanoplus^ fourth stage. (After Einerton.) FIG. 61.— Nymph of Melanoplus, fifth stage. (After Emerton.) FIG. 62.— Melanoplus, adult. in size from time to time till the adult state is reached (Figs. 57 to 62). During this development there is no point at which the insect passes into a quiescent state corresponding to the chrysalis state of a butterfly. Those insects which, like the locust, when they emerge from the egg resemble in form the adult, but still undergo some change, are said to un- dergo an incomplete metamorphosis. In other words, after leaving the egg they do not undergo a complete change of form. Complete Metamorphosis. — Still other insects, like the but- 52 THE STUDY OF INSECTS. terflies, beetles, bees, and flies, leave the egg in an entirely different form from that which they assume when they reach maturity. A butterfly begins its active life as a caterpillar. It feeds and grows, and when full grown changes to a chrys- salis. In this stage it has very little resemblance to a cater- pillar. After a time there bursts forth from the chrysalis shell the butterfly, which looks very little like the chrysalis, and still less like the caterpillar from which it came. In a similar way, from the egg laid by a fly upon a piece of meat there hatches, not a fly, but a footless, worm-like maggot. This when fully grown changes to a quiescent object corre- sponding to the chrysalis of a butterfly. Later from this ob- ject there escapes a winged fly like that which laid the egg. Those insects, like the butterflies and flesh-flies, which when they emerge from the egg bear almost no resemblance in form to the adult insect, are said to undergo a complete met- amorphosis. In other words, the change of form undergone by the insect is a complete one. How Insects groiv — Molting. — The skin of an insect is hard- ened more or less by a horny substance known as chitine (chi'tine). This hardening usually occurs to a much greater extent in adult insects than it does in the young. But in all the skin becomes so firm that it cannot stretch enough to allow for the growth of the insect. The result is, that from time to time an in- sect's skin becomes too small for it, and must be shed. But before this is done a new skin is formed beneath the old one; then the old skin bursts open, and the insect crawls forth, clothed in a soft skin, which stretches to accommodate the increased size of the animal. Very soon, however, this new skin becomes hardened with chitine, and after a time FIG. tea. — Exuviae of nymph of Dragon-fly, it in turn must be shed. This shedding of the skin is termed molting, and the cast skin is some- HEX A POD A. 53 times referred to as the exuvice (ex-u'vi-se). Insects differ greatly as to the number of times they molt : many species molt only four or five times, while others are known to molt more than twenty times. Figure 620. represents the cast skin of a Dragon-fly clinging to a reed. The Egg. — This is the first stage in the existence of any insect, although in some few instances the egg remains in the body of the mother till it hatches. But almost always the eggs are laid by the mother insect on or near the food which gives nourishment to the young. Many of the most interesting habits of insects are connected with the care of the eggs by the parent. The eggs may have smooth oval shells; but often the shells are beautifully ribbed FIG. 63.— Egg of cotton-worm, greatly enlarged. (From the Author's Report and pitted \rig. 03), and some- on cotton insects.) times they are ornamented with spines, and are frequently exquisitely colored. The Larva. — This is the second stage of an insect's life, and is the form that hatches from the egg. Familiar exam- ples of larvae are caterpillars, maggots, and grubs (Fig. 64). FIG. 64.— A caterpillar, the larva of a moth. In fact, nearly all the creatures commonly known as worms are larvae of insects. Away from the ocean we find but few worms, except earthworms, leeches, " hair-snakes," and worm parasites in the intestines of men and animals. Nearly all the rest, except millipedes and centipedes, are larvse of insects, and finally change to forms with wings. 54 THE STUDY OF INSECTS. The larval stage is devoted to growth; the sole business of a larva being to eat and grow. All molting, because of in- creased size, is done in the larval stage, later molts are simply for change of shape. The Pupa. — This is the third stage in the life of an in- sect, and is ordinarily a period of inaction, except that rapid and wonderful changes go on within the body. Very few pupae, like those of mosquitoes, are active. Usually pupae have no power of moving around, but many of them can squirm when disturbed. When the last skin of the larva is thrown off the pupa is re- vealed ; it is an oblong object, FIG. 65.-A pupa of a large moth. ^ frequently apparently headless and footless. In many pupae the skin is a shiny covering like porcelain. If a pupa be examined closely the antennae and legs and wings may be seen ; these are folded up closely and soldered to the breast in the case of tne moths and butterflies (Fig. 65), but free in case of the bees, ants, and beetles. Tlie Chrysalis. — This term is often applied to the pupa of a butterfly. The word is derived from a Greek word mean- ing gold, and came into use because of the golden dots and markings on many of the butterfly pupae. The Cocoon. — Many larvae, especially those of moths, when full grown, spin about the body a silken case, so that when they change to helpless pupae they may be protected from enemies, and from rain and snow ; these silken cases are called cocoons. They are frequently made within a rolled leaves (Fig. 66), or beneath grass and rubbish on the ground, or in cells below the ground. Some hairy caterpil- lars make cocoons largely of their own hairs, which they fasten together with a film of silk. The Nymph. — The terms larva and pupa are only ap- plied to the early stages of those insects that have a com- HEX A POD A. 55 plete metamorphosis ; for in the case of other insects there is no distinct pupa stage. When reference is made to the young of an insect that undergoes an incomplete metamor- FIG. 66. — A large cocoon within a rolled leaf. phosis it is called a nymph. This term is applied to all stages of such an insect from the time they hatch from the egg until they shed their skin for the last time. When a nymph first hatches it has no signs of wings ; but after it molts several times two projections appear on each side of the thorax. These projections become larger and larger, and more wing-like in form with each successive molt. Usually the change in the size of these organs, between the last nymph stage and the adult stage, is much greater than that of any previous molt. With the nymphs of certain families, dragon-flies, crickets, grasshoppers, and locusts, the front pair of developing wings extend back beneath the hind pair instead of covering them ; and by this inverted position of the wings the nymphs may be distinguished from the adults, even in those cases where the adults have only rudimentary wings. The Adult. — This is the last stage or the mature form of the insect. Almost all adult insects except Thysanura have wings, although there are numerous exceptions to the rule ; for there are many cases where wings have been lost through disuse. An insect never grows after it reaches the adult stage, and therefore never molts. There is a popular belief that a small fly will grow into a large fly, but this is not true, for after any insect gets its perfect wings it can 56 THE STUDY OF INSECTS. grow no larger, except that in case of females the body may be distended by the growth of eggs within it. While many adults eat more or less, it is only to sustain life, and not for growth. Indeed, many adult insects take very little food, and some have lost their mouth-parts entirely, through disuse. The adult stage usually lasts for a considerably shorter time than the larval or nymph stages. In fact, it seems planned in the economy of nature that the grown-up insects should live only long enough to lay eggs, and thus secure the perpetuation of the species. THE EXTERNAL ANATOMY OF INSECTS. The subject of insect anatomy is separated into two divi- sions : one, treating of the structure of the body-wall or skeleton ; the other, of the internal organs. The former is termed external anatomy ; the latter, internal anatomy. In our own bodies we find a central framework or skele- ton, about which are arranged the muscles, blood-vessels, nerves, and other organs. But insects are constructed on an entirely different plan : with them the supporting skele- ton is outside, and the muscles, nerves, and other organs are within this skeleton. The difference can be well seen if the figure showing the internal structure of the leg of a May-beetle (Fig. 67) be compared with one of our own limbs, either arm or leg. FIG. 67.— Leg of May-beetle. (After Straus-Durckheim.) The body of an insect is built on the same plan as are its legs. The outside of the body is more or less firm, being hardened by chitine ; and this firm outer wall supports the muscles and other organs, thus serving as a skeleton. The skeleton is therefore, in general outline, a hollow cylinder. HEXAPODA. 57 This hardening of the body-wall is not continuous, but takes place in a series of more or less regular, ring-like bands, which give the well-known seg- mented appearance characteristic of insects, and the animals closely FIG. es.-A Larva, allied to them. Between the hardened ring-like segments the body-wall remains soft and flexible. In this way provi- sion is made fcr the various motions of the body. The ring-like nature of the segments of the body is best seen in larvae (Fig. 68), and in the hinder part of an adult insect (Fig. 69). The movements of the legs, antennae, and certain other appendages are provided for in the same way ; each one is a cylinder made up of several segments, and between these seg- ments the wall of the cylinder remains flexible. When a single segment of the body is examined, the hardened portion is not found to be a continuous ring, but is seen to be made up of several portions more FIG. 69.— A Mole Cricket, or less movable upon each other. Such a hardened portion of the body-wall is termed a sclerite (scle'rite). The sclerites constitute the greater part of the body-wall, the soft membranous portions separating them being in most cases narrow. Usually these narrow portions are mere lines ; they are then called sutures (sut'urs). Frequently the sutures become entirely effaced. We are therefore often unable to distinguish certain sclerites in one species of insect which we know to exist in another. In such cases the effaced sutures are said to be obsolete. If the central portion or thorax of an adult insect be examined, numerous sclerites and sutures can be observed (Fig. 70). $8 THE STUDY OF INSECTS. The subject of external anatomy of insects consists very largely in a study of the scierites of which the different seg- ments of the body and of its appendages are composed. This part of the subject is quite difficult, and will not be discussed here. It is treated at length in a more advanced text-book by the senior author.* FIG. 70. — Side-view of Locust with wings FIG. 71. — Wasp, with . . , ved head, thorax, and abdomen separated. remo The segments of the body in a fully developed insect are grouped into three regions : head, thorax, and abdomen (Fig. 71). In the larval state this grouping of the segments is not well shown. The Head and its Appendages. The head is the first of the three regions of the body. It is supposed to be formed of several body-segments grown together ; but entomologists differ in their views as to the number of segments that have entered into its composition. The head bears the compound eyes, the simple eyes, the antennae, and the mouth-parts. The Compound Ryes. — On each side of the head of an adult insect is an organ, which is recognized at once as an eye. But when one of these eyes is examined with a microscope it is found to present •IG. 72. - Part of com- ...... - , . pound eye, greatly en- an appearance very different from that of the eye of higher animals ; its surface is divided into a large number of six-sided divisions * An Introduction to Entomology by John Henry Comstock Published by the Comstock Publishing Co., Ithaca, N. Y. a EX A POD A. (Fig. 72). A study of the internal structure of this organ has shown that each of these hexagonal divi- sions is the outer end of a distinct eye (Fig. 73). Hence what at . first appears to be a single eye is really an organ composed of hundreds of eyes ; it is termed, therefore, a compound eye. Each of the small eyes of which a compound eye is composed is termed an ocellus (o-cel'lus) (plural ocelli). The number of ocelli of which a com- pound eye is composed varies greatly : there may be not more than fifty, as in certain ants, or there may be many thousand, as in a but- terfly or a dragon-fly. Compound eyes are not found in larvae, though they may possess a group of simple eyes on each side of the head. The Simple Eyes. — In addition to the com- pound eyes, many adult insects possess simple eyes. These are situated between the com- pound eyes. They vary in number from one to four; the most common number is three (see Fig. 71). The simple eyes are usually termed ocelli ; sometimes, stemmata (stem'ma-ta). When the term ocelli is used in descriptive works, if there is nothing in the context to FlG indicate the contrary, it is almost invariably applied to the simple eyes, and not to the ele- ments of the compound eyes. In the same way the term eye usually refers to the com- pound eyes, unless otherwise indicated by the context. The Antenna. — The antennae are a pair of jointed appendages inserted in the head in front of the eyes or between them. They vary in form. In some insects they are thread-like, consisting of a series of similar segments; in others certain segments are greatly modified in form. 73. — Three ocelli, with reti- nulae, from the compound eye of a May-beetle. (After Grenach- er.) The pig- ment has been dissolved away fromt woof them. F, corneal facet; AT, crystalline cone; A Pigment- sheath ; />, chief pigment-cell ; /", pigment-cells of the second order; /?, retinulae. 6o THE STUDY OF INSECTS. The various forms of antennae are designated by special terms. The more common of these forms are represented in Figure 74. These are as follows : 1. Setaceous (se-ta'ceous) or bris- tle-like, in which the segments are successively smaller and smaller, the whole organ tapering to a point. 2. Filiform (fiTi-form) or thread- like, in which each segment is of nearly uniform thickness throughout its length; and the antenna as a whole tapers gradually, if at all, to- wards the tip. 3. Moniliform (mo-nil'i-form) or necklace-form, in which the segments are more or less globose, suggesting a string of beads. 4. Serrate (ser'rate) or saw-like, in which the segments are triangular, FIG. 74. — Various forms of an- tennae. and project like the teeth of a saw. 5. Pectinate (pec'ti-nate) or comb-like, in which the seg- ments have long processes on one side, like the teeth of a comb, or on both sides, like a feather. 6. Clavate (cla'vate) or club-shaped, in which the seg- ments become gradually broader, so that the whole organ assumes the form of a club. 7. Capitate (cap'i-tate) or with a head, in which the terminal segment or segments form a large knob. 8. Lamellate (Jam'el-late), in which the segments that compose the knob are extended on one side into broad plates. TJie Mouth-parts. — No set of organs in the body of an in- sect vary in form to a greater degree than do the mouth-parts. Thus with some the mouth is formed for biting, while with others it is formed for sucking. Among the biting insects some are predaceous, and have jaws fitted for seizing and HEXAPODA. 6 1 tearing their prey ; others feed upon vegetable matter, and have jaws for chewing this kind of food. Among the suck- ing insects the butterfly merely sips the nectar from flowers, while the mosquito needs a powerful instrument for piercing its victim. In this place the typical form of the mouth- parts as illustrated by the biting insects is described. The various modifications of it presented by the sucking insects are described later, in the discussion of the characters of those insects. In the biting insects, the mouth-parts consist of an upper lip, the labrum (la'brum) (Fig. 75, 8); an under lip, the labium (la'bi-um) (Fig. 75, 12); and two pairs of jaws between them. These jaws open sidewise, instead of in a vertical direction, as do the jaws of the higher animals. The upper pair of jaws are called the mandibles (man'di-bles) (Fig. 75, 10); the lower pair, the maxilla (max-iriae) (Fig. 75, u). There may be also within the mouth one or two tongue-like organs, the ^/>////rtr/w^r(ep-i-phar'ynx) and hypopharynx (hy - po - phar'y nx) Fic 75 _Mouth-parts of the Red- *•*- -- "x The epipharynx is attached to the upper wall of the cavity of the mouth, and the hypopharynx to the lower. The position of the hypopharynx is quite analogous, therefore, to that of our tongue. The mandibles vary much in form, bi usually each consists of a single sclent The maxillae of biting insects, on the other . rf.-M-m.of a hand, are very complicated organs each cor Tiger Beetle. ^^ Qf ^^ scleriteS. Each maXlll bears an appendage consisting of several segments; THE STUDY OF INSECTS. appendages are termed the maxillary palpi. In the maxillae of certain biting insects, as the grasshoppers and the ground beetles, there is an appendage usually consisting of two segments : this is the galea (ga'le-a) or outer lobe. In some of these insects, as the ground-beetles and the tiger- beetles, the galea is shaped like a palpus, and thus there appears to be two pairs of maxillary palpi (Fig. 76). The labium is furnished with a pair of jointed appendages ; these are the labial palpi (Fig. 75, u, d). The Thorax and its Appendages. The thorax is the second or intermediate region of the body ; it is the region that bears, in the adult insect, the organs of locomotion, the legs, and the wings when they are present. This region is composed of three of the body- segments more or less firmly joined together ; the segments are most readily distinguished by the fact that each bears a pair of legs. In winged insects, the wings are borne by the second and third segments. The first segment of the thorax, the one next to the head, is named the prothorax ; the second thoracic segment is the mesothorax ; and the third, the metathorax. The Legs. — Each leg consists of the following parts, beginning with the one next to the body (see Fig. 77) : coxa, trochanter, femur, tibia, and tarsus. Each of these parts consists of a single seg- ment except that in certain Hymenoptera the trochanter consists of two segments (Fig. 77, /), and in most insects the tarsus consists of several seg- ments. The number of seg. ments of the tarsus varies from one to six ; the most common number is five. Frequently the first segment of the tarsus is much longer than either of a b c FIG. 77.— Legs of insects : a. Wasp ; b. Ichneumon-fly; c, Bee ; (, trochanter; HI. metatarsus. HEXAPODA. 63 the other segments, and it may also differ greatly in form from them ; under such circumstances it is sometimes desig- nated the metatarsus (met-a-tar'sus) (Fig. 77, /«). The last segment of the tarsus usually bears one or two claws. On the ventral surface of the segments of the tarsus in many insects are cushions of short hairs or of membrane, capable of inflation, or concave plates, which act so as to produce a vacuum, and thus enable the insect to walk on the lower surface of objects. These cushions or plates are called pulvilli (pul-vil'li). In many insects the pulvillus of the last segment of the tarsus is a circular pad projecting between the tarsal claws. In most descriptive works this is referred to as the pulvillus, even though the other pulvilli are well developed. See also page 420. The Wings. — The two pairs of wings are borne by the mesothorax and metathorax, but either or both pairs may be wanting. Thus the Flies, or Diptera, have only the first pair of wings fitted for flight, the second pair being repre- sented by a pair of knobbed threads, the function of which is unknown; and with the Earwigs and Beetles the first pair of wings is wanting, although the mesothorax bears a pair of horny wing covers, which are somewhat wing-like in form, and are commonly described as wings.* In form an insect's wing is a large membranous append- age, which is thickened along certain lines. These thickened lines are termed the veins or nerves of the wing; and their arrangement is described as the venation or munition of the wings. The thin spaces of the wings which are bounded by the veins are called cells. When a cell is complete!) rounded by veins it is said to be closed; but when it extends to the margin of the wing it is said to be open. The wings of different insects vary greatly in structure. * The wing covers or elytra of earwigs and beetles probably correspond to the tegul* of Hymenoptera and to the patagia of Lepidopter are a pair of the side pieces of the mesothorax, the paraptera, grci larged. 64 THE STUDY OF INSECTS. and thus afford excellent distinctions for the purposes of classification. The various parts of the wing have, there- fore, received special names. There is considerable lack of uniformity among entomologists as to the names applied to these parts ; but we have adopted the set of terms defined below as representing the best usage. An insect's wing is more or less triangular in outline ; it therefore presents three margins: the costal margin, or costa (Fig. 78, a, b) ; the outer margin (Fig. 78, b, c) ; and the inner margin (Fig. 78, c, d). The angle at the base of the costal margin (Fig. 78, a) is the humeral angle (hu'me-ral); that between the costal mar- gin and the outer margin (Fig. 78, b} is the apex of the wing ; and the angle between the outer margin and the inner mar- gin (Fig. 78, c] is the anal angle (a'nal). There have been many different sets of names applied to the veins of the wings. Not only have the students of each order of insects had a peculiar nomenclature, but in many cases different students of the same order of insects have used different sets of terms. This condition of affairs was incident to the beginning of the science, the period before the correspondence of the veins in the different orders had been worked out. But now the time has come when it seems practicable to apply a uniform nomenclature to the wing veins of all orders ; and the following set of terms is proposed for that purpose. The principal veins of the wing, those that arise at or near the base of the wing, are termed, beginning with the one lying on the costal margin, the costa (cos'ta), the subcosta, the radius (ra'di-us), the media (me'di-a), the cubitus (cu'bi- tus), and the anal veins. The radius, media, and cubitus are usually branched, and there may be several anal veins. In certain orders of insects two other veins arising near the base ot the wing have been developed : one lying between the media and the radius, the premedia ; and one lying be- tween the media and the cubitus, \.}\z postmedia. HEXAPODA. The veins are frequently designated by numbers; the following table will indicate the correspondence of the num- bers with the names: • I. Costa. II. Subcosta. III. Radius. IV. Premedia. V. Media. VI. Postmedia. VII. Cubitus. VIII. 1 **• I Anal. A. et aL } FIG. 78.— Diagram of wing, showing margin*, angles, and veins. ^.-Diagram of wing of mo th, ,howin* the arrangement of the rein.; -in, IV and VI are wanting. 66 THE STUDY OF INSECTS. The principal veins are indicated by Roman numerals, and when these veins are branched, the branches are indi- cated by Arabic indices appended to the Roman numeral. Thus the branches of radius are designated as III,, III,, III,, etc. (Fig. 79). Figure 78 represents the fore-wing of a butterfly (Danais], and Figure 79 the two wings of a moth (Castnid). In all butterflies and moths veins IV and VI are wanting, and in all butterflies and in many moths the basal part of vein V is also wanting. The arrows in Figure 78 indicate the po- sition of the remnants of this part of vein V. In the hind wing of the moth figured, vein V, has become joined to vein III, so that it appears to be a branch of it ; and in the but- terfly vein V3 appears to be a branch of vein VII, although a short stump, indicated by the lower arrow, shows its former position, in ancient butterflies, before the loss of the basal part of vein V. The Abdomen and its Appendages, The abdomen is the third or caudal region of the body. Its segments are more simple, distinct, and ring-like than those of the other regions. The number of segments of which it appears to be composed varies greatly. In the Cuckoo-flies (CJirysididce) there are usually only three or four visible, while in many other insects nine appear. Except in the lowest order of insects (Thysanurd) the abdomen of the adult bears no locomotive appendages. But many larvae have fleshy appendages which aid in locomotion : these are termed prolegs. In the adult the end of the body in many families is furnished with jointed filaments — the cerci, and caudal setce. Frequently also the body is furnished in the male with organs for clasping — the claspers ; and in the female with saws, piercers, or borers — the ovipositor. In the female of certain insects there is a sting, a modified ovipositor, which is used as an organ of defence ; and the abdomen of plant- lice and certain other insects bears a pair of tubes or tuber- HEXAPODA. 67 cles, through which honey dew is excreted : these are com. monly called honey-tubes ; they are also termed cornicles, nectaries, or siphuncles. THE INTERNAL ANATOMY OF INSECTS. (For advanced students.} As has been shown in the preceding pages, the body-wall serves as a skeleton, being hard, and giving support to the other organs of the body. This skeleton may be represented, therefore, as a hollow cylinder. We have now to consider the arrangement and the general form of the organs contained in this cylinder. For the details of the structure of th . internal organs the student is referred to more special works. The accompanying diagram (Fig. 80), which represents a vertical, longitudinal section of the body, will enable the student to gain an idea of the relative position of some of the more important organs. The parts shown in the diagram are as follows: The body-wall, or skeleton FIG. 80.— Diagram showing the relation of the internal organs. (y) ; this is made up of a series of overlapping segments ; that part of it between the segments is thinner, and is not hardened with chitine. thus remaining flexible and allowing for the movements of the body. Just within the body-wall, and attached to it, are represented a few of the muscles (m) ; it will be seen that these muscles are so arranged that the contraction of those on the lower side of the body would bend it down, while the contraction of those on the opposite side would act in the opposite direction. The alimentary canal (a) occu- pies the centre of the body, and extends from one end to the other. The heart (A) is a tube open at both ends, and lying between the alimentary canal and the muscles of the back. The central part the nervous system («) is a series of small masses of nervous mat connected by two longitudinal cords: one of these masses, lies in the head above the alimentary canal ; the others are situated. 68 THE STUDY OF INSECTS. PLATE II. % A CATERPILLAR (Cossus ligniperita). (After Lyonet.) FiG. i. — Caterpillar opened on the ventral middle line. FIG. 2. — Caterpillar opened on the dorsal middle line. i. principal longitudinal tracheae ; 2, central nervous sys- tem; 3, aorta; 4, longitudinal dorsal muscles; 5, longitudinal ventral muscles; 6. wings of the heart; 7, tracheal trunks arising near spiracles; 8, reproductive organs ; 9, vertical muscles : 10, last abdominal ganglion. HEXAPODA. fy one in each segment, between the alimentary canal and the layer of muscles of the ventral side of the body; the two cords connecting these masses, or ganglia, pass one on each side of the cesophagus to the brain. The reproductive organs (r) lie in the cavity of the abdo- men and open near the caudal end of the body. The respiratory organs are omitted from this diagram for the sake of simplicity. The Muscular System.— We find in insects a wonderfully 'large number of muscles. Those that move the segments of the body form several layers just within the body-wall. The two figures on Plate II represent two caterpillars which have been split open lengthwise, one on the middle line of the back and one on 'the opposite side ; in each case the alimentary canal has been removed, so that only those organs that are attached quite closely to the body-wall are left. From a study of these figures some idea can be obtained of the number and arrange- ment of these muscles. It should be borne in mind, however, that only a single layer of muscles is represented in these figures _ the layer which would be seen if a caterpillar were opened in the way indicated. When these muscles are cut away many other muscles are found ex- tending obliquely in various directions between these muscles and the body-wall. The muscles of insects appear very differently from those (the lean meat) of higher animals. In insects the muscles are either colorless and transparent, or yellowish white ; and they are soft, almost of a gelatinous consistence. When hardened by alcohol or otherwise, and examined with a microscope, they are seen to be crossed by numerous transverse lines, like the voluntary muscles of Vertebrates. As a rule, the muscles of insects are composed of an immense number of distinct fibres, which are not enclosed in tendinous sheaths as with Vertebrates. Rut the muscles that move the appendages of the body are furnished with a tendon at the end farthest from the body (Fig. 81). FIG. 81.— Leg of May-beetle. (After Straus-Durckheim.) Notwithstanding the soft and delicate appearance of the muscles of insects, they are really very strong. One has only to observ, power of leaping possessed by many species to be convim THE STUDY OF INSECTS. PLATE III. A COCKROACH {Peri planet a ori (From Rolleston). HEX A POD A. 7i And the rapidity of their action is even more wonderful than their strength. This rapidity is best illustrated by the muscles that move the wings. Every one has observed gnats and other flies poising in mid air by a movement of the wings so rapid that the eye cannot follow it. Physicists have been able, however, to count these vibrations by de- termining the pitch of the musical note produced in this way. And they tell us that certain gnats vibrate their wings 15,000 times per second. The Alimentary Canal. — The typical position of this is represented in the diagram (Fig. 80); and on Plate III, illustrating the anatomy of a cockroach, its form in that insect is shown. In larvae it is a nearly straight tube, extending from one end of the body to the other. But in adult insects it is usually much longer than the body, and is consequently more or less folded. It is composed of parts differing in form and use. To these parts names have been given similar to those used to designate the corresponding parts in higher animals; thus we distinguish a pharynx, an oesophagus, sometimes a crop, some- times a gizzard, a stomach, a small intestine, and a large intestine. The Adipose Tissue, or Fat. — On opening the body of an insect, especially of a larva, one of the most conspicuous things to be seen is fatty tissue, in large masses. These often completely surround the alimentary canal, and are held in place by numerous branches of the tracheae with which they are supplied. Other and smaller masses of this tissue adhere to the inner surface of the abdominal wall, in the vicinity of the nervous system, and at the sides of the body. In a full- grown larva of Corydalis cornuta I have found the adipose tissue to be greater in bulk than all of the other organs found inside of the muscular walls of the body. In adult insects it usually exists in much greater quantity than in larvae. The Blood-vessels.— In insects all parts of the body cavity that are not occupied by the internal organs are filled with blood. Thus the alimentary canal is completely surrounded with blood, and all the spaces between the muscles. are filled by this fluid. This is a very different arrangement from what occurs in our own body, where the blood is con- tained in a system of tubes, the arteries and the veins. We find, however, that insects are not entirely deprive blood-vessels. For there is one which lies above the ali- mentary canal, just within the middle line of the 1 oft See Figure 80, //, and Plate II, i. This extends from near the caudal end of the abdomen through the thorax mto the head. That part of this system that lies in the abd< THE STUDY OF INSECTS. is usually termed the heart. This is a somewhat complicated organ consisting of several chambers arranged in series, and each communicating with the one in front of it by an opening fur- nished with valves. The number and form of these chambers differ in different in- sects. Fig. 82 represents the heart of a May -beetle. These chambers not only communicate with each other, but com- municate with the body-cavity by means of side openings, which are also furnished with valves. These two sets of valves act in such a way that when a chamber of the heart contracts a stream of blood is forced towards the head, and when it expands the blood rushes into it through the side open- ings, and from the chamber behind it. At- tached to the lower surface of the heart and extending out to the side of the body there is on each side a series of triangular FIGS Hear fM muscles : these have been termed the wings (after Straus-Durckheim): a of the heart (Plate II, 6, and Fig. 83, c). i&TheSt^hi In Fi§ure c they are represented cut away h£&£riSS3S2 from the Caudal Part Of the heart" The muscles are represented as prolongation of the heart, which extends , ' . , through the thorax and into the head, is termed the aorta. The blood is forced by the heart through the aorta into the head, where it escapes into the body cavity. From this point it flows through the body cavity in regular streams, which have definite di- rections, but which are not included in vessels. They, like the ocean currents, are definite streams with liquid shores. The blood is usually colorless, or slightly tinged with green ; but its circulation is made conspicuous by the movements of the large corpuscles with which it abounds. In transparent insects it can be seen pouring forth from the cephalic end of the aorta, bathing first the brain, and then passing to all parts of the body, even out into the appendages. By tracing the course of any one of these currents it will be found to flow, sooner or later, to the cavity between the wings of the heart and the back in which the heart rests, and from which it receives its blood. The Nervous System. — The central part of the nervous system, as cut away from the caudal part of the heart; d, dorsal HEXAPODA. 73 already indicated, consists of a ganglion in the head above the oesoph- agus, and of a series of ganglia, typically one for each segment of the body, lying on the floor of the body cav- ity, and connected by two longitudinal cords. In the head, one of these cords passes on each side of the oesophagus, from the brain to another ganglion in the head belowr the oesophagus, thus forming a nervous collar about the alimentary canal. From each ganglion nerves arise, which supply the ad- jacent parts; and from the thoracic ganglia nerves extend to the legs and wings. This series of ganglia is really a double one ; but each pair of ganglia are more or less closely united on the middle line of the body, and often appear as a single ganglion. Figure 84 gives a general view of the nervous system of Corydalis cormtta. From the brain (a) two large nerves extend to the compound eyes, and a smaller pair to the antennae; the sub- cesophageal ganglion (b) supplies the mouth- parts with nerves ; and each of the thoracic and abdominal ganglia supplies its segment F|c NervolM tem of Of the body. Ctoyrfrilr. (After Leidy.) How Insects Breathe — The Respiratory System. — A common mis- take made by beginners in the study of Entomology is to suppose that insects breathe through the mouth as do the higher animals. Many a beginner has carefully poured chloroform on the head of an insect in the expectation of killing it in that way, and has been sur- prised at his poor success. The truth is, insects breathe through their sides. If an insect be carefully examined, there can be found along the sides of the 1. series of openings (Fig. 85). These are the openings through ,-hich FIG. 85.— Side-view of Locust with wings removed. the air passes into the respiratory system and are termed spiraclt (spir'a-cles). 74 THE STUDY OF INSECTS. The number of spiracles varies greatly in different insects. There is, however, never more than one pair on a single segment of the body. They do not occur on the head, but are borne by each of the thoracic segments, and by the first eight abdominal segments. Thus there are eleven segments that may bear spiracles, but they are always lacking on some one or more of these. These spiracles are either simple openings into the respiratory system, or are provided with valves, sieves, or fringes of hair for the exclusion of dirt. They lead into a system of air-tubes termed tra- chece (tra'che-ae). The accompanying figures will indicate the distri- bution of the main trunks of these tracheae in a cockroach (Figs. 86 and FIG. 86. — Tracheal system of Cockroach. FIG. 87. — Tracheal system of Cockroach. The dorsal integument removed and the The alimentary canal removed to show alimentary canal in place. (After Miall the ventral tracheal communications, and Denny.) (After Miall and Denny.) 87). There is a short trunk arising from each spiracle ; these are all connected together by a large longitudinal trunk on each side of the body, and by numerous transverse trunks. From these large tracheae there arise a great number of smaller ones, not shown in the figures, which branch and subdivide, and extend to all parts of the body. When one dissects an insect the viscera are found to be connected together by the ramifications of these tracheae, so that in order to remove any organ it is necessary to cut some of them. The smaller branches of the tracheae are exceedingly minute, and are intimately associated with the various tissues. By means of these fine tracheal trunks the air is carried to the tissues ; hence the blood plays a much smaller part in respiration than it does in the Vertebrates. Although insects are, strictly speaking, air-breathing animals, many of them, as is well known, live in the water. The study of the ways in which aquatic insects breathe is a very interesting one ; it HEX A POD A. 75 presents to us many wonderful modifications of structure. Some of the more common of these are described in subsequent pages of this book ; in this place we can only make a few generalizations. The various modes of respiration of aquatic insects may be classi- fied under two heads : first, those in which the insects obtain air from above the surface of the water; second, those in which the insects breathe the air that is mechanically mixed with the water. With many aquatic insects the spiracles open beneath the wings, which are folded upon the abdomen. The insect, by coming to the surface of the water and lifting the tip of its wings, forms a cavity be- neath them, into which the air rushes. The insect can then swim through the water, carrying this air witli it in a position where it can be respired. When the air becomes impure, the insect rises to the surface, forces out the air from beneath its wings, and takes in a new supply. Water-beetles and aquatic bugs afford familiar examples of this mode of respiration. Some insects are provided with long tubes connected with their spiracles, by means of which they can draw their supply of air from above the surface of the water while they crawl upon the bottom of shallow ponds. Our most common illustrations of this are bugs of the family Neptdce; but the most remarkable development of this kind is exhibited by certain Dipterous larvae of the family Syrphida. known as Rat-tailed Maggots. Although there are many insects that live in the water and draw their supply of air from above it, the greater number of aquatic insects breathe, as do fishes, the air that is mixed with the water. This is accomplished by organs known as tracheal gills. These are hair-like or more or less plate-like expansions of the body-wall, abundantly supplied with tracheae (Fig. 88). These tracheae divide and subdivide, and their terminations or fine branches are separated from the water that bathes the organ only 1 its thin walls. In this way the air contained in the tracheae is separated from the air in the water only by a d< membrane, which admits of the transfer of gases I them. It will be observed that the difference between a tracheal gill and a true gill (as of fishes, Crustacea, et that the true gill is supplied with vessels containing A which is purified by being brought in contact with ti in the water, while the tracheal gill is supplied withm containing air to be purified. Tracheal gills are usually borne by the abdomen, so times by the thorax, and in case of one genus of Stone-fl 76 THE STUDY OF INSECTS. head. They pertain almost exclusively to the immature stages of insects ; but Stone-flies of the genus Pteronarcys retain them through- out their existence. Tracheal gills vary greatly in form ; in Corydalis they are hair-like, and occur in tufts near the lateral margins of the abdominal seg- ments; in the Cadd ice-worms they are thread-like, more or less branched, and irregularly distributed over the surface of the abdo- men ; and in certain Dragon-flies they are in the form of large plate- like caudal appendages. (Fig. 88.) The Reproductive Organs. — The reproductive organs are situated in the abdomen, as represented in Figure 80. There is a set on each side of the body ; but the two sets usually open by a common tube near the caudal end of the body. In the May-flies and in the Ear- wigs, however, the reproductive organs of each side have a distinct opening. Thus May-flies are often found with two bunches of eggs projecting from the caudal end of the body. All insects are developed from eggs ; but there are some appar- ent exceptions. Thus many flies retain their eggs until after they are hatched, if a proper place for laying them is not found earlier; and in some flies (the Pupipara) the young attain a considerable de- velopment before they are born. In the Plant-lice (Aphidtda) there is a remarkable alternation of reproduction by budding with the sexual reproduction. This is described more fully in the account of that family. THE ORDERS OF THE HEXAPODA. (For advanced students.) The Class Hexapoda, or Insects, is divided in this work into nine- teen orders. This number is somewhat greater than what has been commonly adopted heretofore. But we believe that in the earlier classifications forms were brought together in the same order that are not closely related, and that consequently the present classifica- tion represents better the true relationship of the groups of insects. There has been some hesitation on the part of many entomolo- gists in adopting this division of certain of the old orders, merely for the reason that they felt that the old classification was simpler. But we do not share in this feeling. It seems to us that it is easier for the student to learn the characters of a large number of well-defined groups than it is to learn those of a smaller number of vaguely- defined groups. HEXAPODA. 77 In arranging the orders in a linear series, as must be done in a book, it is impossible to indicate in a satisfactory way either the rela- tion of the orders to each other or the relative rank of the orders. An effort is made to place near together closely allied orders, and to treat first those that are more simple or primitive or generalized in structure, and last those that are more specialized. But this plan could be fully carried out only by having several parallel columns on the pages of the book, each representing a distinct line of descent, an arrangement which, to say the least, is impracticable. What has been done in this work is to place first the Thysanura, which is doubtless the most primitive order. Then follow first the orders that undergo an incomplete metamorphosis, and last, those that undergo a complete metamorphosis. Within these two groups of orders those with biting mouth-parts are placed first, and these are followed by those with sucking mouth-parts, except that in the second group the Coleoptera and Hymenoptera are placed last for want of a better position. We do not intend to indicate by this that these two orders are closely related, or that they are more specialized than the Diptera. In fact, with regard to at least five of the ordersof insects (Hemip- tera, Lepidoptera, Diptera, Coleoptera, and Hymenoptera), it seems idle to us to discuss which is the more highly specialized. Each has been specialized in a direction peculiar to itself ; and to attempt to describe which is the " highest " seems as futile as the discussion by children of the question : " Which is better, sugar or salt? " We give below a table for use in classifying specimens. This table is merely intended to aid the student in determining to which of the orders a specimen that he is examining belongs. No effort has been made to indicate in the table the relation of the orders to each other. TABLE FOR DETERMINING THE ORDERS OF HEXAPODA.* (This table includes only adult insects.') A. Wingless or with rudimentary wings. B. Mandibles and maxillae retracted within the cavity of the head so that only their apices are visible, p. 82 THYSANURA. BB. Mandibles and maxillae more or less prominent and fitted for biting. (See BBB also.) C. Head with long, trunk-like beak. (Boreus.} p. 184. MECOPTERA. * See note at bottom of p. 10. 78 THE STUDY OF INSECTS. CC. Head not prolonged into a trunk. D. Louse-like insects of small size ; body less than one-sixth inch in length. E. Antennae with not more than five segments. (Bird-lice.) p. 100 MALLOPHAGA. EE. Antennae with many segments. (Book-lice.) p. 98. CORRODENTIA. DD. Insects of various forms, but not louse-like, and, except in the case of some ants, with the body more than one-sixth inch in length. E. Abdomen with short, conical, compressed, many-jointed caudal appendages. (Cockroaches^ p. I04...ORTHOPTERA. EE. Abdomen without jointed caudal appendages. F. Legs fitted for jumping. (Wingless Locusts, Grasshop- pers, and Crickets?) p. 104 ORTHOPTERA. FF. Legs fitted for running. G. Abdomen broadly joined to thorax. H. Body linear. (Walking-sticks^ p. 104. ORTHOPTERA. HH. Body white and somewhat ant-like in form. ( Termes.) p. 95 ISOPTERA. HHH. Body neither linear nor ant-like in form. ( Wingless Fire-fly et al. ) p. 494 COLEOPTERA. GG. Base of abdomen strongly constricted. (Ants et al.) p. 599 HYMENOPTERA. BBB. Mouth-parts formed for sucking. C. Small abnormal insects in which the body is either scale-like or gall-like in form, or grub-like and clothed with wax. The waxy covering may be in the form of powder, of large tufts or plates, of a continuous layer, or of a thin scale, beneath which the insect lives. (Coccid Family GRYLLID.E (Gryl'li-dae). The Crickets. The crickets differ from both families of grasshoppers in having the wing-covers flat above and bent sharply down at the edge of the body like a box-cover, instead of meeting in a ridge above the body like a roof. The antennae are long Il6 THE STUDY OF INSECTS. and slender, like those of the Locustidae ; but the form of the ovipositor is quite different in this family, being spear- shaped, instead of sword-like. The males of the crickets have musical organs which are even more elaborate than those of the Katydids and meadow grasshoppers. Here all that part of each wing-cover that lies on the back is occupied by them. This gives the males a very different appearance from the females, the wing- covers of that sex being veined simply. During the latter part of summer and in the autumn the air is filled with the chirping of crickets. It is an interest- ing thing to watch one of these fiddlers calling his mate. By moving quietly in the direction from which the sound comes, and stopping whenever the insect stops chirping, but moving on again when he renews his song, one can get near enough to see how he does it. This can be done even in the night with the aid of a lantern, as the crickets do not seem to mind lights. Figure 133 represents the musical apparatus of a cricket. FIG. 133-— Tegmina of male GryUui. From this it will be seen that the large veins divide the wing- covers into disk-like membranous spaces. If the principal vein which extends diagonally across the base of the wing- ORTHOPTERA. 1 1/ cover be examined with a microscope, it will be seen to be furnished with ridges like those of a file (Fig. 133, ff). On the inner margin of the wing-cover, a short distance toward the base from the end of the principal vein, there is a hardened portion which may be called the scraper. This is shown enlarged at c in the figure. Each wing-cover is there- fore provided with a file and a scraper. When the cricket wishes to make his call, he elevates his wing-covers at an angle of about forty-five degrees with the body ; then hold- ing them in such a position that the scraper of one rests upon the file of the other, he moves the wing-covers back and forth sidewise so that the file and the scraper rasp upon each other. This throws the wing-covers into vibration, and produces the call. There are comparatively few species of crickets, but they represent three quite distinct groups. These can be dis- tinguished as the Mole Crickets, the True Crickets, and the Tree Crickets. I. The Mole Crickets. — These are called Mole Crickets because they burrow in the ground like moles. There are species belonging to the next group, the true crickets, which burrow in the ground ; but the mole-crickets are pre-eminently burrowers. The form of the body is suited to this mode of life. The front tibiae, especially, are fitted for digging ; they are greatly broadened, and shaped somewhat like hands, or the feet of a mole. Figure 134 represents one of these insects. The mole-crickets feed upon the tender roots of various plants, and where they are common they are serious pests. ' FlG' ^f II. The True Crickets. — To this group belong our com- mon, black acquaintances that peep at us from the cracks 118 THE STUDY OF INSECTS. in the paving, or jump across our paths when we walk in the fields. They are com- mon everywhere ; some spe- cies even live in our houses. They usually feed upon plants, but are sometimes predaceous. FIG. •s.-x.-Gryiius aUreviatus. The eggs are laid in the au- tumn, usually in the ground, and are hatched in the follow- ing summer. The greater number of the old crickets die on the approach of winter ; a few, however, survive the cold season. Figure 135 represents the female of a species com- mon in the East. In this species the wings are shorter than usual. III. The Tree Crickets. — The common name of this group was suggested by the fact that these crickets are very apt to inhabit trees ; but they occur also on shrubs, or even on high herbs and tall grass. The most abundant species in the East is the Snowy Tree- cricket, CEcanthus niveus (CE-can'thus niv'e- us). This is a delicate, whitish-green insect, that lives upon shrubs or plants. The female often does serious damage by laying her eggs in raspberry canes, causing them to die above the puncture. Canes thus in- „ FIG. 136. — CEc jured should be cut and burned in the niveus, maie. early spring before the eggs are hatched. Figure 136 shows the male, his closely folded wings showing beneath his delicate transparent wing-covers. The female has her wing- covers wrapped closely around her body, making her look much narrower than the male. CHAPTER XIII. Order PHYSOPODA (Phy-sop'o-da). Thrips. The members of this order have four wings ; these are similar in form, long, narrow, membranous, not folded, with but few or no veins, and only rarely with cross veins ; tJiey are fringed ^vith long hairs, and are laid horizontally along the back when at rest. The metamorphosis is incomplete. The mouth-parts are probably used chiefly for sucking; they are intermediate in form between those of the sucking and those of the biting insects (Fig. 138); t/ie mandibles are bristle-like ; the maxilla are triangular, flat, and furnished with palpi ; and the labial palpi are also present. The tarsi are two- jointed, bladder-like at tip, and without claws. Pull to pieces a clover-blossom or a daisy, and you will probably find at the base of the florets many wee, black, red, or yellowish insects. These are so small that it would take a dozen or more placed end to end to measure an inch ; and when disturbed they are apt to thrust the end of their bodies up in the air as if they meant to sting, looking as ferocious as such small insects can look. They are extremely lively, leaping or taking flight with great agility. Under a microscope their four narrow wings, delicately fringed all around with long hairs, may be seen ; these wings are laid flat down the back when at rest. The red ones are wingless, and are the young of the black species. Some species eat other insects, but most of them live upon vegetation. There is one species, Limot]irips poaphagus (Lim'o-thrips po-aph'a- ng I2O THE STUD Y OF INSECTS. gus) that damages timothy and June-grass very much by working in the upper joints. In the early summer the dead and yellow heads of grasses thus destroyed may be seen everywhere in grass-growing regions. Some species live under the bark of trees. The accompanying figure repre- sents one of these insects very greatly enlarged (Fig. 137). FIG. 137.— Thrifts. FIG. 138.— Mouth-parts of Thrips. (Drawn by J. M. Stedman, under the author's direction.) 8, labrum; 10, mandible; IT, maxilla; 12, labium. The insect infesting grapes, called " The Thrips," is not a Thrips at all, but a leaf-hopper belonging to the Homoptera. The name Physopoda is from two Greek words : pliysao, to blow up, and pous, a foot. It refers to the curious bladder-like feet of these insects. Figure 138 represents the mouth-parts of Thrips. CHAPTER XIV. Order HEMIPTERA (He-mip'te-ra). Bugs, Lice, Aphids, and others. The winged members of this order have four wings ; in one sub-order the first pair of wings are thickened at the base, with thinner extremities which overlap on the back ; in another sub-order the first pair of wings are of the same tJiickncss throughout^ and usually slope at the sides of the bod}'. The mouth-parts are formed for sucking. The metamorphosis is incomplete. The order Hemiptera includes many well-known pests: here belong the true bugs, the lice, the aphids, the scale insects, and many other forms injurious to plants. On the other hand, some of the species are ranked among beneficial insects on account of their predaceous habits ; while still others, as the cochineal and lac insects, furnish us with useful products. The name Hemiptera is from two Greek words : Jiemi, half; and pteron, a wing. It was suggested by the form of the first pair of wings in the true bugs. Here the basal half of these organs is thickened somewhat like the wing-covers of beetles, only the terminal half being wing-like. The second pair of wings are membranous, and when at rest are folded beneath the first pair. The mouth-parts are formed for piercing and sucking. Without dissection, they usually appear as a slender jointed beak, arising at the base of a shorter, pointed upper lip. This beak consists of four bristles, enclosed in a fleshy, 122 7WE STUDY OF INSECTS. jointed sheath (Fig. 139). Two of the bristles represent the mandibles, and two the maxillae. The sheath is supposed to consist of the labium and the grown-together labial palpi. In their transformation the Hemiptera pass through an incomplete metamorphosis ; the young nymphs resembling FIG. i 3 9. — Mouth-parts FIG. 140, a. — Head of an heter- FIG. 140, b. — Head of Bug. (Af- opterous insect. of an homopterous ter Muhr.) insect. the adults more or less closely in form, and the wings being gradually developed at successive molts. This order includes three well-marked groups, which are ranked as suborders. The first of these, the Heteroptera, includes the true bugs. They are placed first, as we believe they resemble the ancient Hemiptera — the first to appear on the earth — more closely than the members of either of the other suborders. The second suborder, the Parasitica, in- cludes the lice. These insects are much lower in structure than the Heteroptera ; but we believe that this simplicity in structure is a result of degradation due to parasitic habits, and therefore really represents a later development than that shown- by the Heteroptera. In other words, the lice are probably descendants of some ancient form resembling some of the existing Heteroptera. Among the Heteroptera the bedbug exhibits a similar downward tendency. The third suborder, the Homoptcra, includes some forms that HEMIPTERA. 12$ are perhaps as primitive as any of the existing Heteroptera; but, on the other hand, we find here forms that represent the widest divergence from the hemipterous type known to us. These three suborders can be separated by the following table : A. Wingless Hemiptera, parasitic upon man and other Mammals, with a fleshy, unjointed beak p. 147 II. PARASITICA. AA. Hemiptera with or without wings, but with a jointed beak. B. First pair of wings thickened at the base, with thinner extremi- ties, which overlap on the back ; beak arising from the front part of the head (Fig. 140, a), p. 123 1. HETEROPTERA. BB. Wings of the same thickness throughout, and usually sloping at the sides of the body; beak arising from the hinder part of the lower side of the head (Fig. 140, b) p.i48.III. HOMOPTERA. Suborder HETEROPTERA (Het-e-rop'te-ra). The True Bugs. People that know but little regarding entomology are apt to apply the term bug to any kind of insect ; but, strictly speaking, only the Hemiptera are bugs, and many restrict the term to members of this suborder. We therefore des- ignate the Heteroptera as the True Bugs. The bugs are very common insects. They abound on grass and on the foliage of other plants. Certain foul-smell- ing members of this group are well-known pests in gardens, and upon berries in fields. In this suborder the first pair of wings are thickened at the base, while the tips, which overlap each other on the back of the insect, are thin and transparent ; and the beak arises from the front part of the head (Fig. 140, a). Some of the Heteroptera live in water, others on land, while still others live on the surface of the water or in marshy places. Each of these modes of life are characteristic of certain fami- lies. The name Heteroptera is from the Greek Jietcros, di- verse, and pteron, a wing. The following synopsis will aid 124 THE STUDY OF INSECTS. the student in learning the characters of the families of this suborder : SYNOPSIS OF THE HETEROPTERA. THE SHORT-HORNED BUGS. Bugs with short antennae, which are nearly or quite concealed beneath the head. Bugs that live within water. The Water-boatmen, Family CORISID^E. (p. 129.) The Back-swimmers, Family NoTONECTioyE. (p. 130.) The Water scorpions, Family NEPID^E. (p. 130.) The Giant Water-bugs, Family BELOSTOMID^:. (p. 131.) The Creeping Water-bugs, Family NAUCORID.E. (p. 133.) Bugs that live near water. The Toad-shaped Bugs, Family GALGULID^E. (p. 133.) THE LONG-HORNED BUGS. Bugs with antennae at least as long as the head, and prominent except in the Phymatida, where they are concealed under the sides of the prothorax. The Semi-aquatic Bugs. The Shore-bugs, Family SALDID^E. (p. 134.) The Broad-shouldered Water-striders, Family VELIID^E. (p. I34-) The Water-striders, Family HYDROBATID.^E. (p. 135.) The Marsh-treaders, Family LIMNOBATID^E. (p. 136.) The Land-bugs. The Land-bugs with four-jointed antenna. The Thread-legged Bugs, Family EMESID/E. (p. 136.) The Assassin-bugs, Family REDUVIID^E. (p. 137.) The Damsel-bugs, Family NABID^E. (p. 138.) The Ambush-bugs, Family PHYMATID^;. (p. 138.) The Flat- bugs, Family ARADID/E. (p. 139.) The Lace-bugs, Family TINGITID^E. (p. 139.) The Bed-bug and the Flower-bugs, Family AcANTHUD.t. (p. 140). The Leaf-bugs, Family CAPSID.E. (p. 140.) The Red-bug Family, Family PYRRHOCORID/E. (p. 141.) The Chinch-bug Family, Family LVG&IDM. (p. 142.) The Stilt-bugs, Family BERYTID^E. (p. 143.) The Squash-bug Family, Family COREID^;. (p. 143.) The Land-bugs with five-jointed antenna. The Stink-bug Family, Family PENTATOMID^E. (p. 144.) ' The Burrower-bugs, Family CYDNID^:. (p. 145). The Negro-bugs, Family CORIMEL/ENID/E. (p. 146.) The Shield-backed bugs, Family SCUTELLERID^E. (p. 146 j HEMIPTERA. 12$ Classification of the Heteroptera. (For advanced students.} In order to use the following table for determining the families of bugs, the student should become familiar with the names applied to different parts of the fore-wings of these insects. The thickened basal portion is composed of two pieces joined together at their sides ; one of these is narrow and is the part next to the scutellum when the wings are closed (Fig. 141, cl)\ this is distinguished as the ctavus (c\a.'vus). The other broader part is the corium (co'ri-um) FlG —Diagram of (Fig. 141, co). The terminal portion of the wing- wing-cover of a , cover is designated as the membrane (Fig. 141, m.) In certain families a triangular portion of the terminal part of the corium is separated as a distinct piece; this is the cuneus (cu'ne-us) (Fig. 141, cii). In certain other cases, a narrow piece on the costal) margin of the corium is separated by a suture ; this is the emboltum (em-bo'li-um) (Fig. 141,^). FIG. 145. Pyrrhocoridte. TABLE FOR DETERMINING THE FAMILIES OF THE HETEROPTERA. A Antennae shorter than the head, and nearly or quite concealed in a cavity beneath the eyes. B. Hind-tarsi without claws. C. Fore-tarsi flattened with a fringe of hairs on the edge, and without claws ; head overlapping the prothorax. p. 129. CORISID/E. CC. Fore-tarsi of the usual form, and with two claws; head in- serted in the prothorax. p. 130 NOTONECTIDJE. 126 THE STUDY OF INSECTS. BB. Hind-tarsi with two claws. C. Caudal end of the abdomen furnished with a respiratory tube composed of a pair of grooved, thread-like organs, p. 130. NEPID^E. CC. Caudal end of abdomen without respiratory tube. D. Legs flattened, fitted for swimming ; caudal end of the ab- domen furnished with a pair of strap-like appendages (these appendages are retractile and are frequently withdrawn from sight), p. 131 BELOSTOMID^E. DD. Legs fitted for walking; abdomen without strap-like caudal appendages. E. Without ocelli, p. 133 NAUCORID^E. EE. Ocelli present, p. 133 GALGULID^E. AA. Antennae at least as long as the head, usually free, rarely (Phy- inatzd(e) fitting in a groove under the lateral margin of the pro- notum. B. Body linear; head as long as the three thoracic segments. p. 136 LlMNOBATIDjE. BB. Body of various forms, but, when linear, with the head shorter than the thorax. C. Last segment of the tarsi more or less split, and with the claws inserted before the apex. D. Body usually elongated; prothorax narrow; beak four- jointed; second and third pairs of legs extremely long and slender, p. 1 35 HYDROBATID-E. DD. Body usually stout, oval, and broadest across the protho- rax ; beak three-jointed; legs not extremely long. p. 134. VELIID^E. CC. Last segment of the tarsi entire, and with the claws inserted at the apex. D. Antennas four-jointed.* E. Wing-covers resembling network, and very rarely (Piesma with any distinction between the corium and the mem- brane, p. 139 TlNGITID/E. EE. Wing-covers of various forms or absent, but not of the form presented by the Tingitidas. See Fig. 165. F. Beak three- jointed. * In certain families there are minute intermediate segments between the principal segments of the antennae. For the purposes of this table these intermediate segments are not counted. HEMIPTERA. 127 G. Wing-covers when well developed with a cuneus (Fig. 143); those forms in which the adult has rudimentary wing-covers have no ocelli, p. 140. . . . ACANTHIID^E. GG. Wing-covers when well developed without a cuneus ; those forms in which the adult has rudimentary wing- covers have ocelli. H. Ocelli wanting. I. Body linear, p. 136 EMESID^E. II. Body greatly flattened, p. 139 ARADID^E. III. Body of ordinary form. p. 137. REDUVIID^E. HH. Ocelli present, though sometimes difficult to see. I. Beak very long, reaching to or beyond the inter- mediate coxae, p. 134 SALDID^L. II. Beak not reaching the intermediate coxae. J. Front legs with greatly thickened femora. p. 138 PHYMATID^E. JJ. Front femora somewhat thickened, but much less than half as wide as long. p. 137. REDUVIID/E. FF. Beak four-jointed. G. Front legs fitted for grasping prey, the tibiae being armed with spines and capable of being closed tightly upon the femora, which are stout. In the forms with long wings the membrane is usually furnished with four long veins, bounding three discal cells which are often open. From these cells diverge veins which form several marginal cells. (Fig. 142). p. 138. NABID^E. GG. Front legs fitted for walking. H. Wing-covers with cuneus. Membrane with one or two closed cells at its base, otherwise without veins. (Fig. 144.) p. 140... CAPSID^E. HH. Wing-covers without cuneus. Membrane with four or five simple or anastomosing veins arising from the base ; or with a large number of veins aris- ing from a cross-vein at the base. I. Ocelli wanting ; membrane with two large cells at the base, and from these arise about eight branching veins. (Fig. 145.) p. 140. PYRRHOCORID^E. II. Ocelli usually present. 128 THE STUDY OF INSECTS. J. Head with a transverse incision in front of the ocelli, which are always present. (Fig. 175.) p. 143 — BERYTID^E. JJ. Head without transverse incision. K. Membrane with four or five simple veins arising from the base of the membrane ; the two inner ones sometimes joined to a cell near the base. (Fig. 146.) p. 142 LYG^ID^E. KK. Membrane with many, usually forked veins, springing from a transverse basal vein. (Fig. 147.) p. 143 COREIDJ-E. OD. Antennae five-jointed. E. Scutellum nearly flat, narrowed behind. F. Tibiae unarmed or furnished with very short spines. p. 144 PENTATOMID^. FF. Tibiae armed with strong spines in rows. p. 145. CYDNID^E. EE. Scutellum very convex, covering nearly the whole ab- domen. F. Lateral margins of the scutellum with a furrow in which the edge of the wing-cover fits when closed. p. 146 CORIMELiENID^E. FF. Lateral margins of the scutellum without a furrow. p. 146 SCUTELLERID^E. In the following pages we have discussed the families of the Hete- roptera in the order in which they are commonly arranged by writers on these insects. The aquatic families are placed first, the semi- aquatic next, and the terrestrial last. We do not believe, however, that this represents well the lines of development of these insects. It seems probable to us that some of the terrestrial forms, as the Penta- tomidae, resemble the ancient Heteroptera more closely than do the aquatic forms ; and that the aquatic forms are really very highly spe- cialized and represent the summit of one of the lines of development. Perhaps the Scutelleridae represent the summit of another line. But as we have been unable to give the matter sufficiently thorough study to warrant our proposing a new arrangement, it seems best to follow the old one, merely indicating our belief in the necessity for a revision of the suborder. HEMIPTERA. \2$ Family CORISID^: (Co-ris'i-dae). The Water-boatmen. These are oval, gray and black, mottled bugs, usually less than half an inch in length, which occur in the streams, ponds, and lakes of the whole United States. The characteristic form and markings of these insects are shown in Figure 148. These Water-boatmen have the body flattened above, and swim upon the ventral surface ; in these respects they differ from the mem- bers of the next family. FIG. ^.-corisa *nd*iata. The body of these insects, as they swim through the water, is almost completely enveloped in air, which glitters like a silver armor. This air is breathed by the insects while they remain under water, and in good water it is purified by contact with the fine particles of air scattered through the water ; so that the insects can breathe their coats of air again and again indefinitely. This is the case especially when they are in their favorite attitude, anchored near the bottom of a pond or aquarium. Here they will remain for a long time clinging to some object by their fore legs, and with their hind legs stretched out sidewise ; these they move frequently as when swimming. The result of this movement is to cause a current of Avater to pass over the coat of air, purifying it. The body of these insects with the air clinging to it is much lighter than water; consequently, whenever they loose their hold upon the object to which they have been clinging, they rise quickly to the surface, unless they prevent it by swimming. They occasionally float on the surface of the water, and can leap into the air from the water and take flight. They feed upon other insects and lay their eggs upon water-plants. All of the North American species of this family belong to the genus Corisa (Cor'i-sa). I3O THE STUDY OF INSECTS. Family NOTONECTID^E (No-to-nec'ti-dae). The Back-swimmers. The Back-swimmers have the back shaped like the bottom of a boat, instead of flat like the true water-boatmen and they differ from all other aquatic bugs in that they always swim on their backs. The favorite attitude of the Back-swimmers is floating on the surface of the water, back downward, with the hind end of the body projecting sufficiently to admit of air being drawn into the space beneath the wings. When in this position their long oar-like hind legs are stretched outward and forward, ready for action. When disturbed they dart away toward the bottom of the pond, carrying a supply of air beneath their wings. Occasionally these insects will float on the surface of the water with their backs uppermost ; and, like the water-boatmen, they can leap into the air from the water and take flight. The Back-swimmers feed upon insects and other small -^ animals. In collecting them care must be *"****) 5 only a single claw on each front tarsus. A third Fl<£j/I5/«r mernber °f tne family is Pelogonus americanus (Pe- ocuiatus. log'o-nus a-mer-i-ca'nus) ; this is a smaller insect, with a more oblong body, and of a velvety-black color. These three are all of the species of this family that have been found in the United States. They all are predaceous. Some members of this family are known to make burrows for themselves, and to live for a part of the time beneath the ground. Family SALDID^; (Sal'di-dae). ^~--t- The Short-bugs. These are certain small bugs, of dark colors with white or yellow markings, and with long antennas, which abound in the vicinity of streams and lakes, and upon damp soils, especially of marshes near our coasts. The shape of these Shore-bugs is shown by Figure 155 ; they belong to the genus Salda, the only genus representing this family in the United States, although many species occur here. FlG I55 _ Some of the Shore-bugs dig burrows, and live SaUa- for a part of the time beneath the ground. They take flight quickly when disturbed, but alight after flying a short distance. Family VELTID^E (Ve-li'i-dae). • The Broad-shouldered Water-striders. There are many bugs that run upon the surface of the water. The greater number of them belong to the next fam- ily; but there are several genera which represent a family distinct from the true Water-striders, and which can be easily distinguished from them by the fact that the body is broad- HEMIPTERA. 135 est across the prothorax. These Broad-shouldered Water- striders constitute the family Veliidce. They pass the greater part of their lives upon the surface of the water, often con. gregating in schools containing hundreds of individuals ; but they usually remain near the banks of the stream or pond, and sometimes they leave the water, mov- ing on the land with great freedom. Like the members of the allied families, they are predaceous. Figure 156 represents one of I these insects somewhat enlarged. FIG. 156. — Rhagoveiia. collar is. Family HYDROBATID^E (Hyd-ro-bat'i-dae). The Water-striders. On the quiet pools of a running stream or the calm waters of a protected pond may be found swarms of slender long-legged insects that seem to find the water surface a pavement well suited for their airy feet. If your approach is stealthy you may see them resting motionless as if ab- sorbed in gazing at their own reflections in the mirror below them ; but disturb them, and so swiftly do they move that they seem but darting lines as they circle around and around each other in a mystic dance. If you watch them closely you may see one leap into the air after some approach- ing insect. These are the true Water-striders. In some of them the body is long and narrow, as shown in Figure 157; in others it is oval ; but in all it is widest back of the pro- thorax, thus differing from the form seen in the pre- ceding family. In the winter they stow conform,. themselves away under the banks or at the bottom of the water, and do not come to 136 THE STUDY OF INSECTS. 1 — — l the surface until lured there by the warm weather of spring, They then lay their eggs, gluing them fast to water-plants. There are members of this family that live on the sur- face of the ocean, hundreds of miles from land. Family LIMNOBATID^E (Lim-no-bat'i-dae). The Marsh-treaders. Only a single species of this family, the Marsh-treader, Limnobates lincata (Lim-nob'a-tes lin-e-a'ta), is found in the United States. This is represented greatly / \ enlarged by Figure 158. Although not an \ / uncommon species, it is rarely seen on ac- count of its small size and quiet habits. It can be recognized by its linear form and the great length of its head, which is longer than the thorax. It crawls about on the surface of the water or mud, or climbs upon ^v s 1 water-plants and sticks projecting from the I water; it seems to prefer stagnant ponds / or marshes. We do not know upon what S it feeds. FIG. 158. — Limnobates Family EMESID^: (E-mes'i-dae). < The Thread-legged Bugs. This family includes a small number of insects in which the body is very slender and the middle and hind legs are thread-like; but the fore legs are fitted for grasping, resembling much those of the Mantes. Our most common species is the Long-legged Emesa, Eme- sa longipes (Em'e-sa lon'- gi-pes), which is repre- sented by Figure 1 59. This FIG. 159.-^ is found upon trees, or sometimes swinging by its long legs from the roofs of sheds or barns. It is predaceous. HEMIPTERA. 137 Family REDUVIID^E (Red-u-vi'i-dae). The Assassin-bugs. There are many bugs which destroy their fellows, but the members of this family are so pre-eminently predaceous that we call them the Assassin-bugs. Although they usually live on the blood of insects, in some cases they attack the higher animals, and occasionally even man suffers from them. Care should be used in collecting them, as some are apt to inflict painful stings with their beaks. In this family the beak is only three-jointed, and when not in use the tip rests in a groove between the fore legs. The family is a very large one, containing more than a hundred American species. In the Atlantic States one sometimes finds, in basements and in rooms but little used, a bug which presents a very curious appearance from having its body and legs completely covered with dust, so that it looks like a living mass of lint as it moves around. This is the Masked Bed-bug Hunter, Opsiccetus personatus (Op-si-cce'tus per-so-na'tus). This species infests houses for the sake of preying upon bed-bugs ; it also feeds upon flies and other insects. Its mask is worn only during youth, and consists of particles of dust and fibres which ad- here to a sticky substance with which the body, legs, and antennae are covered. The adult is black or very dark brown, and is represented by Figure 160. A closely allied species, which is black marked with red, insinuates itself into beds for a less com- mendable purpose than that of its ally, for it sucks human blood at first hand. This insect occurs in the Southern and Western States ; it is the Big Bed-bug, Conor/iinus sanguisu- gus (Co-nor'hi-nus san-gui-su'gus). Nearly all the members of this family, however, live upon trees and other plants, and prey upon insects. 138 THE STUDY OF INSECTS. Family NABID.E (Nab'i-dae). The Damsel-bugs. We have called the members of this family the Damsel- bugs for want of a better name, " little girl " being the mean- ing of Coriscus, the scientific name of our most common genus. Figure 161 represents a wing-cover of a member of this family, and will illustrate the venation char- acteristic of it, although in some species the wings are usually rudimentary. We have two F.G. 161. common members of this family, one blonde and the other black. The Blonde Damsel-bug, Coriscus ferus(Co-ris'cus fe'rus), is about one-third inch in length, and pale yellow, with nu- merous minute brown dots. This species is widely distrib- uted, both in this country and in Europe. It secretes itself in flowers or among the foliage of various herbaceous plants, and captures small in- sects, upon which it feeds. There are several other species that closely resemble this one. The Black Damsel-bug, Coriscus subcoleoptratus FIG. (sub-co-le-op-tra'tus) (Fig. 162), is very common in s the Northern States. It is of a shining jet-black color, with the edge of the abdomen and the legs yellowish. Usually this species has very short, rudimentary wings, but a form with long wings is sometimes found. Family PHYMATID^E (Phy-mat'i-dae). The Ambush-bugs. The most common member of this family is Phytnata wolffii (Phy-ma'ta wolf i-i) (Fig. 163). It is a greenish insect, with a black band across the broadly expanded abdomen. It conceals itself in flowers, and captures FIG. i63. the insects which come to sip nectar. It is espe- •woiffii. cially abundant among the flowers of the golden-rod. HEMIPTERA. 139 It has wonderfully strong, grasping front legs, and can over- come insects much larger than itself. Family ARADID.E (A-rad'i-dae). .***-•'" The Flat-bugs. These are the flattest of all bugs, the body appearing as if it had been stepped upon. They live in the cracks or under the bark of decaying trees. The form of the body is especially adapted for gliding about in these cramped situations. They are usually of a dull -brown color, but are sometimes varied with reddish or pale markings. Figure 164 represents a common species. Family TINGITID.E (Tin-git'i-dae). The Lace-bugs. Dainty as fairy brides are these tiny, lace-draped insects. One glance at the fine white meshes that cover the wings and spined thorax is sufficient to distinguish them from all other insects, for these are the only ones that are clothed from head to foot in fine white Brussels net. They live upon FIG. 165.— Coryth ucn arcu- ata. (From the Author's Report for 1879.) FIG. 166.— Egtfs and nymph of Corythuca. arcuata. (From the Author's Report for 1879- the juices of plants, and in the case of the Hawthorn Tingis (Fig.4i65) sometimes prove too numerous for the health of their plant host. 140 THE STUDY OF INSECTS, They are very small insects, rarely measuring more than one eighth of an inch in length. Their eggs are fastened to leaves, and covered by a brown, sticky substance ; they appear more like fungi than like the eggs of other insects (Fig. 166). Family ACANTHIID^: (Ac-an-thi'i-dae). The Bed-bug and the Flower-bugs. The Bed-bug, Acanthia lectularia (A-can'thi-a lec-tu-la'- ri-a), is a well-known pest over the greater part of the world. It is reddish brown in color, and measures when full-grown from one-sixth to one-fifth inch in length. The body is ovate tMaitctutoH*. in outline and is very flat (Fig. 167). It is wingless, or has very short and rudimentary wing-covers. The Bed-bug is a nocturnal insect, hiding by day in the cracks of furniture and beneath various objects. Bed-bugs are easily destroyed by wetting the cracks in which they hide with corrosive sublimate dissolved in alcohol. This is sold by druggists under the name of bed-bug poison. Py- rethrum powder blown into the cracks will destroy these insects, and, unlike corrosive sublimate, is not poisonous to man. A closely allied species, A. hirundinis (hir-un-di'nis) occurs in nests of the barn-swallow. There are certain small bugs that are closely allied to the Bed-bug, but which have wing-covers that are almost always fully developed. These are the Flower-bugs. They are found in a great variety of situations, ^g^ often upon trees and flowers, sometimes under ^1P bark or rubbish. They are predaceous. Figure 168 represents a wing-cover of one of these insects. Family CAPSIZE (Cap'si-dae). The Leaf-bugs. This is the largest family of the Heteroptera; the members of it live chiefly upon the leaves of plants, HEMIPTERA. 14! from which they derive their nourishment, but some of them are predaceous. The most avail- (fC^—-^ able character for distinguishing these insects is the structure of the wing-covers ; at the base of FlG- l6g- the membrane there are one or two cells, otherwise the membrane is without veins (Fig. 169). More than two hundred species belonging to this fam- ily are known to occur in the United States. Figure 170 represents the Four-lined Leaf-bug, Pcecilocapsus lineatus (Pce-cil-o-cap'sus lin-e-a'tus), a yellow bug, with its prothorax and wing- FIG. T7oZ/v«v- covers marked with black, which is abundant £«/»«* '**"•- jn early summer on the leaves of currant- bushes and of sage. Family PYRRHOCORID,E (Pyr-rho-cor'i-dae). ^^ The Red-bug Family. The members of this family are rather stout and heavily formed bugs, and are generally black or brown, marked with red. Some members of the next family resemble these in markings, but the two families can be distinguished by the venation of FlG< I71< the membrane of the wing-covers. In this family there are two large cells at the base of the membrane, and from these arise branching veins (Fig. 171). The most important species of this family is the Red-bug, or Cotton-stainer, Dysdercus suturellus (Dys-der'cus su-tu- rel'lus) (Fig. 17^2). The adult is of a reddish color ; the wing- covers are pale brown, with pale-yellow stripes. The young are bright red, with black legs. They do much damage by piercing the stems and bolls of the cotton-plant and sucking the juices, but do much more damage by staining the cotton in the open- ing bolls. They also puncture the rind of oranges in Florida, so that decay soon sets in, and the FIG. 172.— z^j-fruit drops. These insects can be trapped by dercut tutu-. * reiiut. laying chips of sugar-cane around the cotton- 142 THE STUDY OF INSECTS. fields. In orange-groves heaps of cotton-seed as well as pieces of sugar-cane will be found useful ; the insects will collect in these places and can be scalded to death. Family LYG/EID^: (Ly-gae'i-dae). The Chinch-bug Family. This, too, is a large family, about one hundred and fifty species being known to occur in the \^^^^ United States. Here the membrane of the wing-covers is furnished with four or five simple veins, which arise from the base of the mem- brane ; sometimes the two inner veins are joined to a cell near the base (Fig. 173). This family contains the Chinch-bug, Blissus leucopterus (Blis'sus leu-cop'te-rus), the most destructive member of the Heteroptera occurring in the United States. Although quite widely distributed, its injuries have attracted most attention in the Missis- sippi Valley, where it has destroyed many million dollars' worth of grain. It is a small Fl bug, measuring less than one sixth of an inch ie*copterus. in length. In Figure 174 it is represented slightly enlarged and greatly enlarged. It is blackish in color, with snowy- white wing -covers, each marked with a dark spot and Y-shaped line, as shown in the figure. The species is di- morphic, there being a short-winged form. There are two generations of the Chinch-bug each year ; they winter as full-grown insects and hide under rubbish. In the early spring they come forth and lay their eggs in fields of grain upon the roots or stems beneath the ground. The eggs hatch in about two weeks. The nymphs are red, and feed at first upon roots; afterwards they attack the stalks of the plants they infest. In about fifty days they get their growth. About this time the whole brood starts out to find new pastures, and they all march on foot in one direction, like an army. Although they are tiny insects they HEM1PTERA. 143 number millions, and so attract much attention. As soon as they find a new field of grain they lay their eggs there for another brood. No satisfactory means of combating this insect was known until recently. But it has now been ascertained that it is destroyed by a contagious disease which can be spread artificially. Diseased bugs are sent to places where the dis. ease does not exist ; and thus the contagion is spread. Extensive experiments are being carried on in Kansas at the time of this writing, and the results so far seem very encour- aging. Family BERYTiDyE (Be-ryt'i-dae). v>v The Stilt-bugs. This family includes a small number of land bugs, in which the body, legs, and antennae are very slender, resembling somewhat the thread-legged bugs (Emesidae). The stilt bugs have the tip of the femora, the tip of the first joint /\\^/\ of the antennae, and the last joint yj\X/V °f the antennae somewhat enlarged fTT^ T (Fig. 175). Only two species have J/MX V I been found in the United States. These are Neides muticus (Ne'i-des mu'ti-cus), which has a prominent spine on the vertex of the head ; and Jalysns spinosus (Jal'y-sus spi- no'sus), which, although spined in other places, lacks the spine on the vertex. These are sluggish insects, found in the undergrowth of woods and in meadows and pastures. Family COREID^: (Co-re'i-dae). The Squash-bug Family. This family is also a very extensive one, including many species. The best character for distinguishing the members 144 THE STUDY OF INSECTS. of it is the nature of the venation of the membrane of the wing-covers. This part is furnished with many veins, most of which spring from a cross-vein near Fu,I76. its base (Fig. 176). The Squash-bug, Anasa tristis (An'a-sa tris'- tis), is a good example of this great family. These when full- grown are brownish-black bugs, with some yellow spots along the edges of the abdomen (Fig. 177), and are dirty yellow on the under side. This bug winters in the adult state, and takes the first opportunity in the spring to lay its eggs on the earliest sprouts of squash and pumpkin vines. As soon as they hatch, the young bugs attack the vines and are apt to destroy them ^ * FIG. 177. — Anasa entirely. The remedy is to protect the young tristis. plants by frames covered with netting. Family PENTATOMID^: (Pen-ta-tom'i-dae). The Stink-brig Family. This is a family the taste and odor of which most of us know to our sorrow. We learn the flavor in one experience, and conclude that once is enough for a lifetime. To those who live in cities it may always remain a mystery why one berry looking just like another should taste and smell so differently ; but all barefooted boys and sun-bonneted girls from the country who have picked the wild strawberries on the hillsides or scratched their hands and faces in raspberry patches know well the angular green or brown bugs that leave a loathsome trail behind them ; and they will tell you, too, that the bugs themselves are worse than their trail, for it is a lucky youngster that has not taken one of these insects into his mouth by mistake with a handful of berries. It should not be concluded, however, that only members of this family possess this disagreeable odor ; for most of the Heteroptera protect themselves by rendering their bodies unpalatable in this way. Doubtless birds soon learn this m HEMIPTERA. 1 45 fact and leave such bugs alone. But it is to members of this family that the expressive name given above is com- monly applied. This nauseous odor is caused by a fluid which is excreted through two openings, one on each side of the lower side of the body near the middle coxae. In this family the antennae are five-jointed ; the scu- tellum, although large, is less than half as long as the abdo. men ; and the front legs are not fitted for digging (Fig. 178). Some species of this family feed upon other insects, and so are very helpful to the farmer, one species especially being a gallant fighter against the potato-beetle. Other species feed entirely upon vegetables, while others live upon both F'|- in^7^~ A vegetable and animal matter. The Harlequin Cabbage-bug or Calico-back, Murgantia kistronica (Mur-gan'ti-a his-tron'i-ca), is very destructive to cabbages, radishes, and turnips in the Southern States and on the Pacific coast. It is black with bands, stripes, and margins of red or orange or yellow. The full-grown bugs live through the winter, and in the early spring each female lays on the under surface of the young leaves about twelve eggs in two parallel rows. The young bugs are pale green, with black spots. They mature in a few days, so there are many generations in one season. It is difficult to find a remedy for this pest, but much can be done by placing cabbage and turnip leaves on the ground in early spring, and thus trapping them when they first come out of their winter quarters. Family CVDNID^: (Cyd'ni-dae). The Bur rower-bugs. These are oval, rounded, or elliptical bugs, with five- jointed antennae ; with the scutellum large, but less than 146 THE STUDY OF INSECTS. half as long as the abdomen ; and with the front legs more or less flattened, fitted for digging (Fig. 179). The species are generally black or very dark brown. They are found burrowing in sandy places, FIG i79V- or on tne surlace of tne ground beneath sticks and nu?t"mi- st°nes> or at tne roots of grass and other herbage. rabiiis. The family is not a large one. The members of it probably feed upon plants ; but it is desirable that further observation be made upon the habits of this family. Family CORIMEUENID.E (Cor-i-me-laen'i-dae). ^- The Negro-bugs. These bugs are mostly black, and are beetle-like in appearance ; some have a bluish or greenish tinge, and all are very convex. The scutellum is very convex, and, as in the following family, covers nearly the whole of the abdo- men. But in this family there is at the base of JfRU the scutellum on each side a short furrow into ' "/JB jV whicn the edge °f the wing-cover fits when at C^*\ rest. All of our species belong to the genus Corimelcena (Cor-i-me-lae'na). FIG. 1 80.— Cori- meia-na at™. These insects infest various plants, and often injure raspberries and other fruit by imparting a disagreeable odor to them. Fig. 180 represents one of these bugs, some- what enlarged. Family SCUTELLERIDJE (Scu-tel-ler'i-dae). % The Shield-backed Bugs. The members of this family resemble the negro-bugs in the shape and size of the scutellum, which covers nearly the whole of the abdomen ; but the sides of the scutellum are not furnished with a groove for receiving the edge of the wing-covers. Fig. 181 repre- FlG ,8l_ Eurygas sents one of these insects enlarged. They ter alternatus- feed upon plants. i HEMIPTERA. 147 Suborder PARASITA (Par-a-si'ta). The Parasita includes certain parasites of man and other mammals, commonly known as lice. They are wingless, and differ from other Hemiptera in having the beak fleshy and not jointed. This suborder is represented in the United States by only one family, the PedicuHda. Family PEDICULID.E (Ped-i-cu'li-dae). The Lice. This family comprises the true lice, which differ from the bird-lice of the order Mallophaga in having sucking mouth- parts. The true lice live on the skin of mammals, and suck their blood. There are three species that infest man : one living on the head, among the hair ; and the other two on the body. Several species infest our domestic animals. The more FIG. ite.—Hamatopinus FlG. 183.— #. eurysttrnus. asini. (From Law.) (From Law.) common of these are the louse of the horse (Fig. 182), and the louse of the cow (Fig. 183). Various substances are used for destroying lice on domes- tic animals : among them are a strong infusion of tobacco, 148 THE STUDY OF INSECTS. an ointment made of one part sulphur and four parts lard, Scotch snuff, powdered wood ashes, and kerosene emulsion. The remedy should be applied thoroughly, and repeated several times at intervals of three or four days, in order to destroy the young which may hatch after the first application. The stable and the places where the cattle are in the habit of rubbing should also be whitewashed or sprayed with kerosene, or strong kerosene emulsion. Suborder HOMOPTERA (Ho-mop'te-ra). Cicadas, Leaf-]wppers, Aphids, Scale-bugs and of hers. The Homoptera includes insects of widely diversified form, but which agree, however, in 'having the wings when present of the same thickness throughout, and usually slop- ing roof-like at the sides of the body when at rest, and in having the beak arise from the hinder part of the lower side of the head (Fig. 140, b}. The name is from two Greek words : homos, same ; and pteron, a wing. This suborder includes nine families, which are designated as follows : The Cicadas, Family ClCADlD^E (p. 149). The Lantern-fly Family, Family FULGORID^E (p. 151). The Spittle Insects, Family CERCOPIDJ3 (p. 152). The Leaf-hoppers, Family JASSID^; (p. 153). The Tree-hoppers, Family MEMBRACID^E (p. 154). The Jumping Plant-lice, Family PSYLLID^E (p. 155). The Plant-lice, Family APHIDID^E (p. 156). The Aleyrodes, Family ALEYRODID/E (p. 163). The Scale-bugs, Family COCCID^E (p. 164). CLASSIFICATION OF THE HOMOPTERA. (For advanced students.} TABLE FOR DETERMINING THE FAMILIES OF THE HOMOPTERA. A. Beak evidently arising from the head ; tarsi three-jointed ; anten- nae minute, bristle-like. HEM1PTERA. 149 B. With three ocelli, and the males with musical organs. Usually large insects, with all the wings entirely membranous, p. 149. ClCADIDiE. BB. Ocelli only two in number or wanting ; males without musi- cal organs. C. Antennae inserted on the sides of the cheeks beneath the eyes. p. 151 FULGORID;E. CC. Antennae inserted in front of and between the eyes. D. Prothorax not prolonged above the abdomen. E. Hind tibiae armed with one or two stout teeth, and the tip crowned with short stout spines p. 152.. . CERCOPID/E. EE. Hind tibiae having a row of spines below p. 153. JASSID^E. DD. Prothorax prolonged into a horn or point above the abdomen, p. 154 MEMBRACID/E. A A. Beak apparently arising from between the front legs, or absent; tarsi one or two jointed ; antennae usually prominent and thread- like, sometimes wanting. B. Tarsi usually two-jointed ; wings when present four in number. C. Wings transparent. D. Hind legs fitted for leaping; antennae nine or ten jointed. p. 155 PSYLLID^E. D. Legs long and slender, not fitted for leaping; antennae three to seven jointed, p. 1 56 APHIDID/E. CC. Wings opaque, whitish ; wings and body covered with a whitish powder, p. 163 ALEYRODID/E. BB. Tarsi one-jointed ; adult male without any beak, and with only two wings; female wingless, with the body either scale- like or gall-like in form, or grub-like and clothed with wax. The waxy covering may be in the form of powder, of large tufts or plates, of a continuous layer, or of a thin scale beneath which the insect lives, p. 164 Family ClCADlD/E (Ci-cacTi-dae). The Cicadas (Ci-ca'das). The large size and well-known songs of the more common species of this family render them familiar objects. It is only necessary to refer to the Periodical Cicada (or the seventeen- year locust, as it has been improperly termed) and to the THE STUDY OF INSECTS. Dog-day Harvest-fly (Fig. 184) to give an idea of the more striking characters of this family. We have several species much smaller than either of these ; but their characteristic form and the presence of three ocelli are sufficient to distinguish them from the members of the other families. The Periodical Cicada, Cicada scp- tendedm (Ci-ca'da sep-ten'de-cim), is very generally known in this country, owing to the great numbers in which it appears, at long intervals of time. This periodical appearance is due to the long time required for the nymphs to obtain their growth — either seven- teen or thirteen years — and to the fact that all the members of one generation appear in the adult state at about the same time. The adult female lays her eggs in slits which she makes in the twigs of trees. Small fruit is sometimes in- jured in this way. The eggs hatch in about six weeks. The young nymphs finding no attraction in a world of sun- shine and of flowers, drop to the ground and bury them- selves in the earth, thus commencing a voluntary seclusion which lasts for years. They live by sucking the juices from the roots of trees. In May of the seventeenth year after their retirement to their earthy cloisters they crawl up to the surface of the ground, like renegade monks ; and, leav- ing their nymph-skins clinging to the tree-trunks, like cast- off garments of penance, they come forth, broad-headed, broad-bodied, clear-winged creatures, well fitted to get all the experience possible out of a world whose frivolities they have so long scorned. But, like other creatures, they find a life of dissipation very exhausting, and after a few weeks they sing their last song, lay their eggs, and pass away. In the South these insects live only thirteen years under HEM1PTERA. l$\ ground, but in the North it requires seventeen years for a nymph to reach maturity. More than twenty distinct broods of this species have been traced out. In many localities several broods coexist ; this explains the fact that in such places these insects ap- pear several times during a single period of seventeen years. There is a common species of Cicada known as the Dog- day Harvest-fly or Lyreman, Cicada tibicen (Ci-ca'da ti-bi'cen), Avhich requires only two years for its development, and as there are two broods of this species the adults appear every year. This Cicada (Fig. 184) is black and green in color, and more or less powdered beneath. And its song is the high, sharp trill that comes to us, midsummer noons, from the depths of trees where the singer is hidden amid the foliage, all unconscious that its shrill note has for centuries been a theme for poets. Family FULGORID.E (Ful-gor'i-dae). The Lantern-fly Family. This family is remarkable for certain exotic forms which it contains. Chief among these is the great Lantern-fly of Brazil, which is figured in many popular works on insects. Scarcely less strange are the Candle-flies of China and the East Indies. The popular names of these insects refer to the fact that they are phosphorescent, but we know of no native species that possesses this peculiarity. There does not seem to be any typical form of the body characteristic of this family. The different genera differ so greatly, that on superficial examination they appear to have very little in common. Some even resemble butterflies and moths, while others might easily be mistaken for neuropterous genera. The most useful character for recognizing these insects is the form and position of the antennae. These are bristle- shaped, and inserted in a button-shaped base on the side of 152 THE STUDY OF INSECTS. the cheek beneatli the eyes. Although the Fulgoridae are vegetable feeders, none of our species have attracted the at- tention of agriculturists. There are, however, certain exotic species which do great injury to crops. The two accompanying figures will serve to show the wonderful variations in form of these insects ; many other types exist. Figure 185 represents a common species of Sco- lops (Sco'lops), which occurs in grassy places. In this genus the head is greatly prolonged, as with the exotic Candle-flies. FIG. \%$.—Scolops. FIG. \^.—Ortnenis septen- trionalis. Figure 186 represents Ormenis septentrionalis (Or'me-nis sep- ten-tri-o-na'lis), a beautiful pale-green species powdered with white, which feeds on wild grape-vines, drawing nourishment from the tender shoots and mid-ribs of the leaves during its young stages. Family CERCOPID^E (Cer-cop'i-dae). The Spittle Insects or Frog-hoppers. During the summer months one often finds upon various shrubs and herbs masses of white froth. In the midst of each of these masses there lives a young insect, a member of this family. In some cases as many as four or five insects inhabit the same mass of foam. The froth is supposed to consist of sap, which the insect has pumped from the plant, by means of its beak, and passed through its alimentary canal. It is asserted that these insects undergo all their transformations within this mass ; that when one is about to molt for the last time, a clear space is formed about its body ; the superficial part of the foam dries, so as to form a vaulted roof to a closed chamber, within which the change HEMIPTERA. 153 of the skin is made. The adult insects wander about on herbage and trees. They have the power of leaping well. The name frog-hoppers has doubtless grown out of the fact that formerly the froth was called "frog-spittle," and was supposed to have been voided by tree-frogs from their mouths. The name is not, however, inappropriate, for the broad and depressed form of our more common species is something like that of a frog. In this family the antennae are inserted in front of and between the eyes ; the prothorax is not prolonged back of the abdomen (as in the Membracidae) ; and the tibiae are armed with one or two stout teeth, and the tip crowned with short, stout spines, as shown in Figure 187. This figure represents the most com- mon spittle insect of the Eastern United States, l^Ll ApJirophora guadrangu/aris (A-phroph'o-ra. quad- ran-gu-la'ris), and one of its tibiae greatly enlarged. *\ Family The Leaf-hoppers. The most abundant members of the Homoptera, except perhaps the Aphids, are the leaf-hoppers. Large numbers of them can be easily collected by sweeping grass, herbage, or the foliage of shrubs. The leaf-hoppers are more slender than the spittle insects, and are also distinguished by the form of the hind tibiae, whicli are nearly or quite as long as ^le abdomen, curved, and armed with a row of spines on each margin (Fig. 188). FIG. m.-proco- Among the leaf-hoppers that have attracted attention on account of their injuries to vegeta- tion are the following: The destructive Leaf-hopper, Cicaditla cxitiosa (Ci-cad'u-la ex-it-i-o'sa), which is represented greatly enlarged by Figure 189, sometimes infests winter wheat to a serious extent in the Southern States. The Grape- 154 THE STUDY OF INSECTS. vine Leaf-hopper, Erythroneura vitis (E-ryth-ro- neu'ra vi'tis), is a well-known pest that infests the leaves of the grape. It is about one-eighth inch in length, crossed by two blood-red bands, and a third dusky one at the apex. It is often improp. erly called the " Thrip" by grape-growers. But the term Thrip or better Thrips should be restricted to members of the order Physopoda. The Rose ^cicad^r*. Leaf-hopper, Empoa roses (Em'po-a ro'sae), is also a (FromThe well-known pest, as it often swarms on the leaves ReponTd? of roses, doing great damage. Its presence is usually indicated by numerous white cast skins adhering to the lower side of the leaves. The leaf-hoppers can be destroyed by a strong solution of soap, or with kerosene emulsion. In vineyards, where the use of these substances would injure the fruit, they can be trapped by two persons carrying a screen covered with tarred paper on one side of a row of vines, while a third per- son walking on the other side of the row frightens them from the vines on to the screen. Dead leaves and other rubbish, among which these insects hibernate, should be burned during the winter. Family MEMBRACID^; (Mem-brac'i-dae). The Tree-hoppers. Nature must have been in a joking mood when tree- hoppers were developed, for these little creatures are most FIG. 190. — Tree-hoppers. HEM IP TERA . 1 5 5 comically grotesque in appearance. In general outline they resemble beech-nuts, except that many have humps on their backs. The prothorax is prolonged back- ward like a roof over the body, often quite covering it. If the young entomologist wishes to laugh, let him look at the faces of tree-hoppers through a lens (Fig. 190). Their eyes always have a droll look, and the line that separates the head balus' from the prothorax gives them the appearance of wearing glasses. In some cases the prothorax is elevated above the head, so that it looks like a peaked nightcap ; in others it is shaped like a Tam-o'- Shanter ; and sometimes it has horns, one on each side, which have given one species the name of the Buffalo Tree-hopper. Many species of this family live upon bushes or small trees, and are all good leapers ; hence the com- mon name, Tree-hoppers. Some species ex- crete honey-dew, and are attended by ants. All feed upon plants, but they seldom appear FlG. 194._7>/«. in sufficient numbers to do much damage. The accompanying figures will show some of the more common forms seen in this strange family (Figs. 191-194). Family PSYLLID^: (Psyl'li-dae). T/ie Jumping Plant-lice. The jumping plant-lice are comparatively small insects ; our more common species measuring only from one-eighth to one-sixth inch in length, and it is rare that we find any twice that size. When examined with a lens they appear like tiny Cicadas (Fig. 195). Their hind legs are formed for jumping ; their antennae are nine or ten jointed, and their tarsi are only two-jointed. Figure 197 repre- sents the wings of a common species. FlGen?lr7edSylla' The Psyllidse subsist entirely upon the I56 THE STUDY OF INSECTS. juices of plants, and some of them cause serious injuries. Many species form galls ; one of the larger of these infest the Celtis or Hackberry. FIG. 196.— The Pea-rtree Psylla, greatly enlarged. FIG. 197. — Venation of Wings: j, stigma; c, clavus; c. s., claval suture. The most destructive member of this family in the United States is the Pear-tree Psylla, Psylla pyricola (Psyl'la py-ric'o-la). This is a minute species, measuring only one- tenth inch in length to the tip of the folded wings (Fig. 196). But it occurs in such large numbers that it has destroyed extensive pear orchards, by sucking the sap from the smaller limbs and twigs. It can be destroyed by spraying the infested trees with kerosene emulsion imme diately after the leaves have expanded in the spring. Family APHIDID^E (A-phid'i-dae). The Plant-lice or Aphids (Aph'ids). The plant-lice are well-known insects; they infest nearly all kinds of vegetation in all parts of the country. Our most common examples are minute, soft-bodied, green insects, with long legs and antenna::, which appear on various plants in the house and in the field. Among our common species are both winged and wingless forms (Fig. FIG. 198.— A Grou 198). There are a great number of species, nearly all of HEM IP TERA . 1 5 / which are of small size. In our largest species the body measures only about one-fourth inch in length, and usually these insects are very much smaller. The body is usually more or less pear-shaped. The winged forms have two pairs of delicate, transparent wings. These are furnished with a few simple veins, but the vena- tion is more extended than in either of the two following families. The first pair of wings is larger than the other, and the two wings of each side are usually connected by a compound hooklet. The beak is three-jointed, and varies greatly in length ; sometimes it is longer than the body. The compound eyes are prominent, and ocelli are also usually present. The antennae are from three to seven jointed. On the back of the sixth abdominal segment there is, in many species, a pair of tubes, through which a sweet, transparent fluid is excreted. In some genera these organs are merely perforated tubercles, while in still other genera they are wanting. The fluid which is excreted through the abdominal tubercles is the substance known as honey-dew. It is some- times produced in such quantities that it forms a glistening coating on the leaves of the branches below the plant-lice, and stone walks beneath shade-trees are often densely spotted with it. This honey-dew is fed upon by bees, wasps, and ants. The bees and wasps take the food where they find it, paying little if any attention to its source ; but the ants recognize in the plant-lice useful auxiliaries, and often care for them as men care for their herds. This curious re- lationship will be discussed farther under the head of Ants. It is easy to see what benefit ants derive from this asso- ciation with plant-lice, and how they should learn that it is worth while for them to care for their herds of honey-pro- ducing cattle. Little has been done, however, to point out the great benefit that accrues to the plant-lice from this re- lationship. It seems fair to assume that the plant-lice are greatly benefited, else why has the highly specialized appa- 158 THE STUDY OF INSECTS. ratus for producing the honey-dew been developed ? Writers long ago showed that ants protect plant-lice by driving away from them lady-bugs and other enemies. Recently, how- ever, Professor Forbes has demonstrated that, in certain cases at least, a more important service is rendered. In his studies of the Corn Plant-louse, Aphis maidis (A'phis mai'dis), he found that this species winters in the wingless, agamic form in the earth of previously infested corn-fields, and that in the spring the plant-lice are strictly dependent upon a species of ant, Lasius alienus (Las'i-us al-i-e'nus), which mines along the principal roots of the corn, collects the plant-lice, and conveys them into these burrows, and there watches and protects them. Without the aid of these ants, the plant-lice were unable to reach the roots of the corn. In addition to honey-dew, many Aphids excrete a white substance. This may be in the form of powder, scattered over the surface of the body, or it may be in large floccu- lent or downy masses ; every gradation between these forms exists. The plant-lice are remarkable for their peculiar mode of development. The various species differ greatly in the de- tails of their transformation, but the following generaliza- tions can be made. There are several distinct forms in each species, each form playing a peculiar part in the history of the species. If a colony of plant-lice be examined during the summer months it will be found, usually, to consist very largely of wingless individuals ; these are females, which reproduce without the intervention of males. This is the wingless agamic form. In many cases this form gives birth to living young, instead of laying eggs ; and the reproduction of this form is so rapid, that it would be disastrous to the species, by the destruction of the infested plants and the consequent starving of the insects, if another form of the species did not arise. But from time to time young are produced which become winged, and thus the spread of HEMIP TERA . 159 the species is provided for. This winged form also con- sists entirely of females, and is known as the winged agamic form. They produce in turn the wingless agamic form, a single-winged individual, which has flown to a new plant, starting a new colony. Generally on the setting in of cold weather, or in some cases on the failure of nourishment, the weather being still warm, there is produced a generation including individuals of both sexes. These are known as the sexual forms. The males may be either winged or wingless, but these true females are always wingless. The sexual forms pair, and the female produces one or more true eggs. It is in this state that the species usually pass the winter, and consequently these eggs produced by the sexual form are often called the winter eggs, to distinguish them from egg-like bodies produced by the agamic forms of certain species, and which are termed pseudova (pseu-do'va). From the winter egg there hatches, usually in the spring, an agamic female, which, as she is the stock from which the summer generations spring, is often called the stem-mother. The peculiar reproduction of the agamic forms is often termed reproduction by budding. Plant-lice are often very destructive to vegetation. The ordinary methods of combating them are either by the use of a strong solution of soap or with kerosene emulsion. Plant-lice vary greatly in their habits. Certain species live in the ground on the roots of plants. The Lettuce Earth-louse, Rhizobius lactucce (Rhi-zo'bi-us lac-tu'cae), is a good illustration. This occurs on the roots of lettuce, often in great numbers. Other species are found on the roots of grasses or herbaceous plants and usually accompanied by ants. On the other hand, many species, in fact the majority of Aphids, pass their lives on the foliage of plants, infesting especially the tenderer leaves. Familiar examples are the Cabbage Aphis, Aphis brassicce (A'phis bras'si-cae), the Apple- tree Aphis, Aphis malt, the Cherry-tree Aphis, Mysus cerasi (My'sus cer'a-si), and the Peach-tree Aphis, Mysus persicce 160 THE STUDY OF INSECTS. (My'sus per'si-cae). The last three are almost invariably attended by ants. The Plant-lice of the genus Lachnus (Lach'nus) are usually found on the limbs of trees and shrubs. To this genus belong our largest Aphids. some of them measuring one-fourth inch in length. Figure 199 represents one of these enlarged. Some species of plant-lice live both on FIG. 199. — Lachnus. the roots and on the leaves of plants. One of these is the Grape Phylloxera, Phylloxera vastatrix (Phyl- lox-e'ra vas-ta'trix), which is the most important enemy of the grape. The presence of this insect is manifested by the vines in two ways : first, in the case of certain species of grapes, there appear upon the lower surface of the leaves fleshy swellings, which are more or less wrinkled and hairy ; these are hollow galls, opening upon the upper surface of the leaf, and containing a wingless agamic plant-louse and her eggs ; second, when the fibrous roots of a sickly vine are examined, we find, if the disease is due to this insect, that the minute fibres have become swollen and knotty ; or, if the disease is far advanced, they may be entirely decayed. Upon these root-swellings we also find an agamic, wingless, egg -laying plant-louse, the author of the mischief. The insects found upon the roots differ slightly from those found within the galls, but their specific identity is now generally accepted. Owing to the great injury which this species has done to the vineyards of France, hundreds of memoirs have been published regarding it. But as yet no satisfactory means of destroying it has been discovered. The difficulty lies in the fact that the insecticide must be one that can penetrate the ground to the depth of three or four feet, reaching all the fibrous roots infested by the insect. It must be a substance that can be cheaply applied on a large scale, and it must also be something that will kill the insect without injury to HEMIPTERA. l6l the vine. Carbon bisulphide has been used to some extent for this purpose. Where the vineyards are so situated that they can be submerged for a period of at least forty days during the winter, the insect can be drowned. But this method is obviously of limited application. It is found that vines growing in very sandy soil resist the attacks of the Grape Phylloxera. This is supposed to be due to the difficulty experienced by the insect in finding passage through such soil. Another well-known example of the plant-lice that make galls is ColopJia ulmicola (Coro-pha ul-mic'o-la), which makes the Cockscomb Elm-gall. This gall is shaped more or less like a cock's comb, and is very common on the upper side of the leaves of the elm. There is a group of species of plant-lice known as the Woolly Aphids, on account of a white more or less downy or waxy substance with which the bodies of these insects are covered. Large numbers of one of these species are often found crowded together on the under side of the branches of alder. This species is known as the Alder-blight, ScJiisoncura tesscllata (Schiz-o-neu'ra tes-sel-la'ta). In addition to the white excretion with which the body is covered this insect excretes large quantities of honey-dew. The result is that the branches infested by this insect, and those beneath the clusters of Aphids, become blackened with fungi that grow upon this secretion. There is also a curious fungus which grows in large spongy masses immediately beneath the- clus- ters of plant-lice; this is known to botanists as Scorias spongiosum. It is evidently fed by the honey-dew that falls upon it. The Beech-tree Blight, Schisoneura imbricator (im-bri- ca'tor), infests both the twigs and leaves of beech. Like the preceding species it occurs in clusters of individuals, each of which is clothed with a conspicuous downy excre- tion. These clusters often attract attention by the curious 162 THE STUDY OF MSSCTS. habit that the insects have of waving their bodies up and down, the plume-like masses of excretion rendering them very conspicuous. When an infested limb is jarred the Aphids emit a shower of honey-dew. Owing to the abun dance of this secretion, the branches and leaves of an infested tree become blackened by growths of fungi, as wirti the preceding species. The Woolly-louse of the Apple, Schizoneura lanigera (la-nig'e-ra), is one of the best-known pests of the fruit- grower. In its most conspicuous form it, appears on the trunks and limbs of apple-trees, in clusters of individuals, which are conspicuous on account of the woolly excretion with which the bodies are covered. It is especially in- jurious to young trees, the bark of which becomes deeply pitted and scarred by its attacks. The bark apparently ceases to grow at the point of attack, but swells into a large ridge about the cluster of lice, leaving them in a sheltered pit. • The lice also frequently congregate in the axils of the leaves and the forks of the branches. This species resembles the Grape Phylloxera in having a root- inhabiting form, which causes knotty swellings on the fibrous roots. It is the presence of this form that makes this pest such a difficult one to combat. For as it works deep in the ground upon the fibrous roots of trees, the same difficulties are met in attempting to destroy it that are pre- sented by the Grape Phylloxera. In fact, except in case of an especially valuable tree, we do not believe that it will pay to attempt to save a tree that has become badly infested by the woolly aphis. It will be cheaper to dig the tree up and burn it, and devote the ground to some other use. Another species of tree can be safely planted in the same place, but not an apple. Great care should be taken in putting out trees from a nursery to see that they are free from this pest If there is any doubt the trees should be washed, roots and all, in a strong solution of soap. It is well also to put in the forks of the trees pieces of hard soap, which will HEMIPTERA. 163 be dissolved and washed down by the rains. This will serve to destroy certain other pests, as well as the woolly aphis. In case it is desired to rid an infested tree of this pest, the trunk form should be washed off with a strong solution of soap applied with a sponge, taking care to destroy all eggs ; and the ground should be treated with carbon bisulphide, as for the Grape Phylloxera. Family ALEYRODID.E (Al-eu-rod'i-dae). The Aleyrodes (Al-eu-ro 'dcs\ The insects of the genus Aleyrodes were for a long time classed with the Coccidae. In their immature state they are scale-like in form (Fig. 200), and often somewhat resemble certain species of Lecanium. But the mature insects differ so much from the Coccids that the genus has been sepa- rated as a distinct family. They are very small insects; the species with which I am acquainted have an expanse of wings of about one eighth of an inch. Both sexes are winged ; and, as with other Hemiptera except the Coccids, there are two pairs of wings. In the adult state, all the species are nearly of the same color ; the wings are white, sometimes spotted ; the body is usually yellowish, sometimes pinkish, and more or less spotted with black. The most striking character presented by the adults, in addition to the fact that both sexes are winged and each has two pairs of wings, is the presence of a whitish powder with which the wings and body are covered. It is this character that suggests the name of the genus, which is from the Greek aleurodes, like flour. 164 THE STUDY OF INSECTS. Family COCCID^: (Coc'ci-dae). The Scale-bugs or Bark-lice, Mealy-bugs, and otJiers. The family Coccidae includes the Mealy-bugs, the Scale- bugs or Bark-lice, and certain other insects for which there are no popular names. In this family we find those mem- bers of the Hemiptera that depart most widely from the type of the order. In fact this is a very anomalous group, the species differing greatly in appearance, habits, and meta- morphoses from those of the most closely allied families. Not only do the members of this family appear very unlike other insects, but there is a wonderful variety of forms within the family, and even the two sexes of the same species differ as much in the adult state as members of distinct orders. The males of Coccidae, unlike all other Hemiptera, undergo a complete metamorphosis. The adult males have only a single pair of wings, the hind wings being represented by a pair of club-like halteres. Each of these is furnished with a bristle, which in all the species we have studied is hooked, and fits in a pocket on the wing of the same side (Fig. 202). The male in the adult state has no organs for procuring food, as the mouth-parts disappear during the metamorphosis of the insect, and a second pair of eyes ap- pear in their place. The adult female is always wingless, and the body is either scale-like or gall-like in form, or grub- like and clothed with wax. The waxy covering may be in the form of powder, of large tufts or plates, of a continuous layer, or of a thin scale, beneath which the insect lives. Among the Coccidae are found many of the most serious pests of horticulturists. Scarcely any kind of fruit is free from their attacks, and certain species of scale-insects and mealy-bugs are constant pests in conservatories. The ease with which these insects or their eggs can be transported long distances while yet alive, on fruit or living plants, has HEMIPTERA. 1 65 caused many species that infest cultivated plants to become world-wide in distribution. During recent years much attention has been paid to devising methods of destroying these pests. Various soapy FIG. aoa.-The Scurfy Bark-louse. Chio*a*pi* /ur/urus : i, scales natural size; ia, scale of male enlarged ; 16, adult male enlarged ; ic, scale of female enlarged. or alkaline washes, and one made of lime, salt, and sulphur, are now used on the trees with deciduous foliage; the wash is applied during the winter while the trees are naked. In the case of orange and lemon trees, which are constantly clothed with leaves, a large tent is lowered over the tree and a 1 66 THE STUDY OF INSECTS. poisonous gas (hydrocyanic-acid gas) is generated within the tent. A number of useful insects belong to this family. Several species furnish dye-stuffs. The best known of these is Coccus cacti, the dried bodies of which are known as Cochi- neal. The stick* lac of commerce, from which shell-lac or shellac is prepared, is a resinous substance excreted by a species, Carteria lacca (Car-ter'i-a lac'ca), which lives on the young branches of several tropical trees, and the bodies of these insects, which are obtained from the stick lac, furnish the coloring agents known as lac dye. China wax is another substance for which we are indebted to this family. It is the excretion of an insect known as Pe-la, Ericerus pe-la (E-ri- ce'rus). In fact many species of this family excrete wax in considerable quantities. Among the more prominent members of this family are the following: The Cottony-cushion Scale, Icerya pttrchasi (I-ce'ry-a pur'cha-si). — This beautiful in sect (Fig. 203) was at one time the most dangerous insect pest in California, and did a great amount of injury. It is an introduced Australian spe- cies, and has been subdued to a great extent by the intro- duction of an Australian Lady- bug, Vedalia (Ve-da'li-a), which preys upon it. The body of the adult female is scale-like, dark orange-red, and has the dorsal surface more or less covered with a white or yel- lowish-white powder. The in- sect secretes a large egg-sac, which is beautifully ribbed. The Mealy-bugs, Dactylopius (Dac-ty-lo'pi-us). — The HEMIPTERA. I67 FIG. lo^.—Dactylopius citri, fe- male, enlarged. (From the Author's Report for 1880.) FIG. 204. — Dactylopius longispi- nus, female, enlarged. (From the Author's Report for 1880.) FIG. ao6.— A". *ntes sp., on Quercus agrifoliti. Adult females on stem ; immature males on leaves. (From the Author's Report for 1880.) i68 THE STUDY OF INSECTS. Mealy Bugs are the most common and the most noxious of green-house pests ; and in the warmer regions, as in Florida, they infest plants in the open air. Two species are shown greatly enlarged in Figures 204 and 205. These insects are extremely difficult to combat, as the white powder with which the body is clothed protects them from the sprays and washes ordinarily used. Kcnnes. — Species of this genus are common upon oaks wherever they grow. These insects are remarkable for the wonderful gall-like form of the adult females. So striking is this resemblance, that they have been mistaken for galls by many entomologists. Figure 206 represents a species of this genus upon Quercus agrifolia. The gall-like swellings on the stem are the adult females ; the smaller scales on the leaves are the immature males. Orthezia (Or-the'zi-a). — The members of this genus occur not uncommonly on vari- ous weeds. They are remark- able for the calcareous secretion with which the body is clothed. This is in the form of long plates. Figure 207 represents a nymph ; in the adult female the secretion becomes more elongated posteriorly, and forms a sac containing the eggs mixed with a fine down. Latei^ when the young are born, they remain in the sac till they have themselves secreted a sufficient FIG. 207. — Orthezia, 'enlarged. (From nrnniint of the lamellar miffpr the Author's Report for 1880.) am to cover them. Puhnnaria (Pul-vi-na'ria). — This genus includes species in which the body of the female resembles Lecanium, de- scribed below, but which excrete a large cottony egg-sac. This egg-sac is not ribbed, but is of the form shown in HEMIPTERA. I69 Figure 208. The species figured here is sometimes very injurious to maple-trees ; it also infests grape-vines and other plants. FIG. zoB.—Putvina •terabilis. Female on grape, natural size. (From the Author's Report for 1880.) Lecanium (Le-ca'ni-um). — The species of the genus Le- canium abound everywhere ; they occur on all kinds of FIG. 209. — Lecanium olett ; ia, insect enlarged. (From the Author's Report for 1880.) plants, both in conservatories and in the open air. Some of them are known to gardeners as " soft-scales." But the I/O THE STUDY OF INSECTS. scientific name is coming into general use; it is a common thing now to hear fruit-growers speak of the Lecaniums, especially in California. The Lecaniums are naked scale insects, the scale being the body of the insect. These insects are flattish or more or less hemispherical, the differ- ent species differing in form, and are usually dark brown in FIG. 210. — Lecanium hesperidum. (From the Author's Report for 1880.) color. The eggs, or the young in the viviparous species, are deposited beneath the scale-like body of the female. Figure 209 represents Lecanium olea (o'le-ae), which is very com. mon in California, where it is known as the black scale; Figure 210, the soft scale, Lecanium iicsperidum (hes-per'i- dum), which is common on various plants in all parts of HEMIPTERA. 171 this country; and Figure 211, the hemispherical scale, Lecanium hemispharicum (hem-i-sphaer'i-cum), which occurs in conservatories everywhere, and in the open air in Cali- fornia. The Armored-scales Sub-family ZTzas/ft'%? (Di-as-pi'nae). — The great majority of the common scale insects of this FIG. an.— Lecanium hemisphcericum ; 3^, insect enlarged. (From the Author's Report for 1880.) country differ from the forms described above in that the body of the insect, except for a very short period after birth, is covered with a scale composed in part of an excre- tion of the insect and partly of molted skins. Thus in the Lecaniums the scale-like object is the body of the insect; but in the case of the Oyster-shell Bark-louse, the Pernicious 1/2 THE STUDY OF INSECTS. Scale, and of many other forms, the scale-like object com- monly seen is not the insect, but an armor beneath which it lives. The young insects of this sub-family resemble in general appearance those of other scale insects. Their active stage, however, is much shorter. After crawling about over the IMG. 212. — Chionaspis pinifolite : 2, scales on Pinus strobus, natural size, leaves stunted; 2.— Cerydali When about two years and eleven months old, the larva leaves the water, and makes a cell under a stone or some other object on or near the bank of the stream. This occurs dur- ing the early part of the summer ; here the larva changes to a pupa. In about a month after the larva leaves the water the adult insect appears. The eggs are then soon laid ; 1/8 THE STUDY OF INSECTS. these are attached to stones or other objects overhanging the water. They are laid in blotch-like masses, which are chalky-white in color, and measure from half an inch to nearly an inch in diameter. A single mass contains from two thou- sand to three thousand eggs. When the larvs hatch they at once find their way into the water, where they remain until full grown. There are other common species of the family which closely resemble Corydalis but are smaller, the larger ones measuring less than two and a half inches in length, and having a wing expanse of not more than four inches. These insects also differ from Corydalis in having three ocelli and in lacking the sharp tooth-like angles on the sides of the back part of the head. See Figure 215 of the adult Corydalis. These species belong to the genus Chauliodes (Chau-li'o-des). Chauliodes pecticornis (pec-ti-cor'nis) is a common species with grayish wings and feather-like antennae. Chauliodes serricornis (ser-ri-cor'nis) is also common ; this is a brownish- black species with the wings spotted with white, and with serrate antennae. Family RAPHIDIID^E (Raph-i-di'i-dae.) ..^ The Rafhidians (Ra-pJiid' i-ans). ;ct^~^ i-> " -n^ i ^ ic W*'? The members of this family are found in this country only in the far West. They are strange-appearing insects, the prothorax being greatly elongated, like the neck of a camel (Fig. 217). The female bears a long, slender, sickle-shaped ovipositor at the end of the abdomen. The fore legs resemble FIG. 217.— Raphidia, female. the other pairs of legs, and are borne at the hinder end of the prothorax. The larvae are found under bark and are carnivorous. We have found them common under the loose bark of the Eucalyptus. They also occur in orchards, and doubtless do good by destroying the larvae and pupae of the Codlin-moth. NE UROP TERA . 1 79 r Living specimens of these insects have been sent to Aus- tralia by our government in the hope of introducing the species there, and thus doing something towards repaying the debt that we owe that country for the Australian Lady- bug, which has rendered us great service in the destruction of the Cottony-cushion Scale in California. The family is represented by two genera, Raphidia (Ra- phid'i-a) and Inocellia (In-o-cerii-a). In the former there are three simple eyes on the top of the head between the compound eyes ; in the latter these ocelli are wanting. Family MANTISPID^: (Man-tis'pi-dae). The Mantis-like Neuroptera. The members of this family are even stranger in appear- ance than the Raphidians. Here, as in that family, the prothorax is greatly elongated ; but the members of this family can be easily recognized by their remarkable fore legs, which are greatly enlarged and resemble those of the Praying Mantes in form (Fig. 2 1 8). These legs are fitted for seizing prey ; and, in order that they may reach farther forward, they are joined to the front end of the long pro- thorax. In the adult state these insects are predaceous; while the larvae, so far as is FlG. 2^_ManiiJa, In the specimer known, are parasitic in the ^what" in 2?.^ ^^thLwibr» egg-sacs of spiders. Five species of the family are known from the United States ; four of these belong to the genus Mantispa (Man- tis'pa) and one to Symphasis (Sym'pha-sis). ISO THE STUDY OF INSECTS. Family CHRYSOPID^E (Chry-sop'i-dae). The Lace-winged-flies or Aphis-lions. If one will search the foliage of herbs, shrubs, or trees, there may be found, running rapidly around on the leaves, sturdy, spindle-formed, little insects that have great sickle- shaped jaws (Fig. 219). These larvae are always hungry, and will kill and eat any insects that they can overpower ; FIG. 219.— Eggs, larva, cocoon, and adult of Chrysofla. but as they are especially destructive to plant-lice, they are called Aphis-lions. When an Aphis-lion is full grown it rolls itself up into a tiny ball and weaves around itself a glistening, white cocoon, which looks like a large seed-pearl. It may be supposed that while the Aphis-lion is secluded in this pearly 1 it repents its greedy, murderous ways, and changes in spirit ; at least the body changes greatly, for, after a time, a circular lid is made in the cocoon, and out of this emerges a beautiful, dainty creature, with delicate-veined, green tings, a pale green body, slender, brown antennae, and a pair of large eyes that shine like melted gold. It s NEUROPTERA. igl sometimes called Golden-eyes, and sometimes, a Lace-winged- fly, from its appearance. The Lace-wing is a prudent mother ; she knows that if she lays her eggs together on a leaf the first Aphis-lion that hatches will eat for his first meal all his unhatched brothers and sisters. She guards against this fratricide by laying each egg on the top of a stiff stalk of hard silk about half an inch high. Groups of these eggs are very pretty, looking like a tiny forest of white stems bearing on their summits round glistening fruit. When the first of the brood hatches, he scrambles down as best he can from his egg perch to the surface of the leaf, and runs off, quite unconscious that the rest of his family are reposing in peace high above his head. The mouth-parts of these larvae are very unusual in form. The mandibles are very long ; on the lower side of each of them there is a furrow the entire length ; into this furrow the long and slender maxilla fits. In this way the mandible and the maxilla of each side form a tube, through which the blood of the prey of the insect can be drawn. This explains why an Aphis iion holds its prey on the tips of its long jaws, at arm's length, as it were, while sucking its blood. Nearly all of the members of this family belong to the genus Ckrysopa (Chry-so'pa). Family HEMEROBllDyE (Hem-e-ro-bi'i-dae). The Hemerobians (Hem-e-ro'bi-ans). The common members of this family are rather dark- colored insects, with the wings mottled with dark brown or smoky specks, and with some of the veins between the costa and subcosta forked. The most conspicuous member of 'the family is Polys- tcechotes punctatus (Pol-ys-tcech'o-tes punc-ta'tus), which is represented natural size by Figure 220. The larva is unknown. 1 82 THE STUDY OF INSECTS. The larger number of the species of this family belong to the genus Hemerobius (Hem-e-ro'bi-us). These are small- ish insects, the largest of which expands hardly an inch. They occur in forests, and especially on cone - bearing trees. The FIG. 220.— Poiystackotes punctatus. }arvae bear a strong resem- blance to the Aphis-lions, and like them feed upon Aphids and other small insects. After sucking the blood from their victims, they make cloaks for themselves of the empty skins. Family MYRMELEONID^E (Myr-me-le-on'i-dae). The Ant-lions and others. The Ant-lions, Myrmeleon (Myr-me'le-on). — In sandy places beneath overhanging cliffs, beneath buildings, and along sandy banks where the sun shines warmest, there may be found, in all parts of our land, little, funnel-shaped pits one or two inches across (Fig. 221). The sides are smooth and as steep as the sand will lie ; and at the bottom may be seen two small curved objects. All is still and motionless until some ant, hurrying along with mind intent upon business, FlG> 22I-Pitfa11 of an Ant-lion. carelessly runs over the edge of one of these pitfalls. Then the ant commences to slide down, while some force below throws out the sand from under its struggling feet, until it slides into the bottom, where literally jaws of death are awaiting it. For the curved objects are a pair of jaws, attached to a strong head, and closely connected with a greedy stomach. If we dig out the owner of the jaws we find it a spry, humpbacked creature, which moves backward more easily than forward. It is worth while to collect some NEUROPTERA. 183 of these larvae, and place them in a basin of sand, and watch them build their pits. They do this by using the head for a shovel. Sometimes when an ant seems likely to escape, the Ant-lion will throw up a torrent of sand so that it will descend on the victim, knocking it back into the pit. When ready to change to a pupa the Ant-lion makes for itself a little, round cocoon of sand fastened together and lined with silk. The adult Ant-lion is a graceful insect with long, narrow, delicate wings, and a slender body (Fig. 222). FIG. 222.— 'Larva, cocoon with pupa-skin projecting, and adult of an Ant-lion. Certain members of this family differ from the ant-lions in having long, filiform antennae, which are suddenly en- larged at the end. These belong to the genus Ascalaphns (As-cal'a-phus). CHAPTER XVI. Order MECOPTERA (Me-cop'te-ra). The Scorpion- flies and others. The members of this order have four wings ; these are membranous, and furnished with numerous veins. The head is prolonged into a beak, at the end of which biting mouth parts are situated. The metamorphosis is complete. This is a small order composed of very remarkable in- sects. The most striking character common to all is the shape of the head, which is prolonged into a beak (Fig. 223). The name Mecoptera is from two Greek words ; A^,^ mccos, length ; and pteron, a wing. This order li^^ includes only a single family, the Panorpidcz. \ Family PANORPID/E (Pa-nor'pi-dae). ^ The Scorpion-flies and others. TK We have found representatives of this family quite abundant on rank herbage growing on FIG. 27, -Head tne banks of a shaded stream ; we have also *°r/*.' ° "" found them in damp woods where there was a luxuriant undergrowth of herbaceous plants. These insects take flight readily when disturbed ; they are car- nivorous both in the adult and in the larval state. The larvae larvae so far as known are remarkable on account of their great resemblance to caterpillars. Not only is the form of the body like that of a caterpillar, but the abdomen is fur- nished with fleshy pro-legs. There are, however, eight pairs of these ; while caterpillars, as a rule, have only five. 184 MECOPTERA. 185 The most common members of this family are the Scorpion-flies, Panorpa (Pa-nor'pa). These are called Scor- pion-flies on account of the peculiar form of the caudal part of the abdomen of the male (Fig 223). This at first sight suggests the corresponding part of a scorpion ; but in reality the two are very different. The last segment, instead of ending in a sting like that of a scorpion, is greatly enlarged and bears a pair of clasping organs. The wings are nar- row but are well developed, being longer than the body. In our more common species they are FlG „<._/>,. yellowish, spotted with brownish black (Fig. 224). norpa' adult- Very closely allied to the Scorpion-flies are the insects of the genus Bittacus (Bit'ta-cus). These insects have long narrow wings, long legs, and a slender abdomen. They re- semble crane-flies very closely when on the wing. In this genus the caudal appendages of the male are not enlarged as in Panorpa. The species of the genus Boreus (Bo're-us) are remarka- ble for occurring on snow, in the winter, in our Northern States. CHAPTER XVII. Order TRICHOPTERA (Tri-chop'te-ra)c The Caddice-flies or Caddice-worms. The members of this order have four wings; these are membranous, furnished with numerous longitudinal veins but with only few cross veins, and are more or less densely clothed with hairs. The mouth-parts are rudimentary. The meta- morphosis is complete. The Caddice-flies are moth-like insects which are com- mon in the vicinity of streams, ponds, and lakes ; and they are also frequently attracted to lights at night. The body-wall of these insects is soft, being membran- ous or at the most parchment-like, and is thickly clothed with hairs. There are usually four ample wings. These are membranous ; but the fore pair are more leathery than the hind pair. When not in use they are folded against the sides of the abdomen, in an almost vertical position, and give the insect a narrow and elongated appearance (Fig. 225). The wings are more or less densely clothed with hairs ; and in some cases the hairs are scale-like in form. The hind wings are usually broader than the fore wings, and are often longitudi- Fic. 225.— Caddice-fly. ,, , ,. , . A 11 i nally folded in repose. All have nu- merous longitudinal veins, but the cross veins are few. The name of the order is from two Greek words ; thrix, a hair ; and pteron, a wing. The order includes only a single family, the Phryganeida. 186 TRICHOPTERA. l8/ Family PHRYGANEID^: (Phryg-a-ne'i-dae). The Caddice-flies or Caddie e-worms. The young naturalist loves to lie face downward on the bank of a brook, and, with shaded eyes, watch the busy life that goes on there. Among the astonishing things he sees are little bundles of sticks or masses of stones moving about the bottom of a quiet pool as if they were alive ; and yet if he takes them out they seem dead enough. But when he pulls them apart he finds that each is a tube lined with silk within which a whitish larva lives. This larva, when it wishes to move, puts out the front part of its body, so that it can creep with its legs over the bottom of the stream, or climb up and down water-plants, dragging its house along after it. When molested it draws back into its tube, and is safe. Larvae of this sort are called Caddice- worms ; and the adult insects are known as Caddice-flies. There are very many species of Caddice-worms ; and each species makes a particular kind of tube. Some Caddice- worms are carpenters, building their houses of straws or sticks. These are usu- ally placed lengthwise the body (Fig. 226); but certain species that FIG. 226. make their houses chief- ly of straws fasten the straws crosswise like the logs of a log-house (Fig. 227). These log-house builders often have the curious habit of decorating,their houses by fastening snail-shells to the outside. And strangely enough they do not always take empty shells for this purpose ; we have found shells containing living snails securely fastened FlG- "7- to the outside of the house of a Caddice-worm. In this case the snail was afforded comparatively rapid transportation whether it desired it or not. Fortunately the species that --&- f ,88 THE STUDY OF INSECTS. make this style of house live in still water, and may, there- fore, be easily kept alive in aquaria. There are caddice-worm houses closely resembling in plan those just described but differing in appearance, being made of bits of moss. Sometimes the houses are built of leaves ; these may be fastened so as to form a flat case ; or are ar- ranged in three planes, so as to form a tube, a cross-section of which is a triangle. Other Caddice-worms are masons, building their houses of grains of sand or of small stones. Sometimes these houses are tubes very regular in outline, being composed only of grains of sand fastened together with silk ; but certain spe- cies of Mason Caddice-worms fasten larger stones on each side of this tube of sand (Fig. 228). Some of the species that f FIG. 228. FIG. 229. build tubes of sand make spiral houses which very closely resemble in form snail-shells (Fig. 229). Whether stones or wood are used to build these houses the material is always fastened together by silk, which the larvae spin from the mouth in the same manner as do cater- pillars. In some species the case is composed entirely of silk. Figure 230 represents the form of such a case, which * is common in some of our lakes. Among the simplest of the various forms of houses built by Caddice-worms are those made by certain species that live under stones in rapid streams. These consist merely of a few pebbles fastened to the lower surface of a larger stone by threads of silk. In the space between these pebbles the worm makes a more or less perfect tube of silk, within which TR1CHOP TERA . 1 89 it lives. Very little respect for the architectural skill of these builders is commanded by their rude dwellings. But if one looks a little farther, something will be found that is sure to excite admiration. The dweller within this rude re- treat is a fisherman ; and stretched between two stones near by can be seen his net. This is made of silk. It is usually funnel-shaped, opening up-stream ; and in the centre of it there is a portion composed of threads of silk extending in two directions at right angles to each other, so as to form meshes of surprising regularity. It is as if a spider had stretched a small web in the water where the current is the swiftest. These nets occur in rapids between stones, but in many places they are to be found in greater numbers along the brinks of falls. Here they are built upon the surface of the rock, in the form of semi-elliptical cups, which are kept distended by the current. Much of the coating of dirt with which these rocks are clothed in summer is due to its being caught in these nets. We have not yet observed the owners of the nets taking their prey from them ; but we cannot doubt that they are made to trap small insects or other ani- mals that are being carried down-stream ; for the larvae of the sub-family to which these net-builders belong, the Hy- dropsydiin(Z, are known to be carnivorous. It should be noted here, however, that the greater number of Caddice- worms are herbivorous. When a Caddice-worm gets ready to change to a pupa it retires into its house and builds a door to keep intruders out ; but the door always has an opening to allow the water to flow in so that the pupa can breathe. Sometimes a simple grating of silk is made over the entrance. On one occasion the writer had the good fortune to ob- serve a Caddice-fly leave the water and take its first flight. The specimen was one of the net-building species, Hydrop- syche (Hy-drop-sy'che), which I was breeding in an aquarium in my laboratory. It swam to the surface of the water repeatedly, using its long middle legs. When swimming, 190 THE STUDY OF INSECTS. these legs were extended at right angles to the body like a pair of oars. The insect was unable to crawl up the vertical side of the aquarium, and after clinging to it for a short time it would lose its hold and sink back to the bottom. After watching it for a time I lifted it from the water by means of a stick. At this time its wings were in the form of pads, which were but little, if any, longer than the wing-pads of the pupa, as shown by the cast pupa-skin found floating on the water. The instant the creature was free from the water its wings expanded to their full size, and immediately it flew away several feet. In my efforts to catch the insect I found that it had perfect use of its wings, although they were so recently expanded. The time required for the insect to expands its wings and take its first flight was scarcely more than one second ; it was certainly less than two. As these insects normally emerge from rapidly-flowing streams which dash over rocks, it is evident that if much time were required for the wings to become fit for use, as is the case with most other insects, the wave succeeding that which swept one from the water would sweep it back again and destroy it. CHAPTER XVIII. Order LEPIDOPTERA (Lep-i-dop'te-ra). The Moths or Millers, the Skippers, and the Butterflies. The members of this order have four wings ; these are membranous, and covered with overlapping scales. The month- parts are formed for sucking. The metamorphosis is complete. The name of this order is from two Greek words : lepis, a scale ; and pteron, a wing. It refers to the fact that the wings of these insects are covered with scales. Every lad that lives in the country knows that the wings of moths and butterflies are covered with dust, which comes off upon one's fingers when these insects are handled. This dust when examined with a microscope is found to be composed of very minute scales of regular form ; and when a wing is looked at in the same way, the scales are seen arranged with more or less regularity upon it. The body, the legs, and other appendages are also covered with scales. The scales of Lepidoptera are modified hairs. That is, they are hairs which, instead of growing long and slender as hairs usually do, remain short, but grow very wide as com- pared with their length. Every gradation in form can be found from the ordinary hair-like form, which occurs most abundantly upon the body, to the short and broad scale, which is best seen upon the wings. There is a great difference among the insects of this order regarding the regularity of the arrangement of the scales 191 192 THE STUDY OF INSECTS. upon the wings. With some of the lower moths the scales are scattered irregularly over the wings. But if the wing of one of the higher butterflies be examined with a microscope, the scales will be found arranged in regular, overlapping rows; the arrangement being as reg- ular as that of the scales on a fish or of the shingles on a roof (Fig. 231). In the upper part of the figure the membrane is represented with the scales re- moved. The use of the scales on the wings is to strengthen them. We thus see that the wings of these insects are furnished with much fewer cross veins than are the wings of similar size in other orders. A secondary use of these scales is that of ornamentation ; for the beautiful colors and markings of these insects are due entirely to the scales, and are destroyed when the scales are removed. Upon the body, legs, and FIG. 231.— Part of wing of butterfly, greatly magnified. FIG. 232.— Maxillae of cotton-moth, and tip of same enlarged other appendages, the scales and hairs doubtless serve to protect the insect, being a sort of armor. The mouth-parts of moths and butterflies are especially adapted for sucking nectar from flowers. If the head of a butterfly be examined, there will be found a long sucking LEffDOPTERA. 193 tube, which when not in use is coiled on the lower side of the head between two forward-projecting appendages. This long sucking tube is composed of the two maxillae, greatly elongated, and fastened together side by side. In Figure 232 there is represented a side view of the maxillae of a moth ; and in Figure 233 a cross-section of these organs. Each FIG. 233. — Cross-section of maxillae. maxilla is furnished with a groove, and the two maxillae are so fastened together that the two grooves form a tube through which the liquid food is sucked. As a rule the maxillae of insects of this order are merely fitted for extracting the nectar from flowers, but sometimes the tips of the maxillae are armed with spines, as shown in Figure 232. This enables the insect to lacerate the tissue of ripe fruits and thus set free the juice, which is then sucked up. Many moths do not eat in the adult state ; with these the maxillae are wanting. The two forward -projecting organs between which the maxillae are coiled when present are the labial palpi. In some moths the maxillary palpi are also developed. The larvae of Lepidoptera are known as caterpillars. They vary greatly in form and appearance ; but are usually cylindrical, and provided with from eight to sixteen legs, — six thoracic legs, and from two to ten abdominal legs. The thoracic legs, which are finally developed into the legs of the adult, have a hard external skeleton ; and are jointed, taper- ing, and armed at the end with a little claw. The abdominal legs, which are shed with the last larval skin, are thick, 194 THE STUDY OF INSECTS. fleshy, without joints, elastic or contractile, and are generally surrounded at the extremity by numerous, minute hooks (Fig. 234) ; they are termed pro-legs. FIG. 234. — Larva of a Hawk-moth. Most caterpillars, except the larvae of butterflies, spin cocoons (Fig. 235). In some instances, as in case of the FIG. 235.-Cocoon of a moth. silkworms, a great amount of silk is used in the construction cocoon; in others the cocoon is composed principally LEPIDOPTERA. 195 of the hairs of the larva, which are fastened together with a fine web of silk. In the pupae of Lepidoptera the developing wings and legs are folded upon the sides and breast ; the whole being enclosed in a hard skin (Fig. 236). The members of this order as a rule feed upon plants, and are not aquatic ; some, as the Clothes-moth and the species that destroy Scale-bugs, feed FlG- ^.-Pupa of a moth, on animal matter, and. a very few feed upon plants below the surface of the water. More than six thousand species of Lepidoptera are known to occur in America, north of Mexico. These rep- resent more than sixty families. In order to give a synopsis of the Lepidoptera it is necessary to enter into rather difficult technical details. Hence this is done in that portion of this chapter designed for advanced students and printed in fine type. The prin- cipal divisions of the Lepidoptera that are appropriately discussed here are three : the moths, the skippers, and the butterflies : — The Moths. — These are the insects commonly called millers. Most of the species fly by night and are frequently attracted to lights. When at rest the wings are either wrapped around the body, or are spread horizontally, or are folded roof-like on the abdomen ; they are not held in a vertical position above the body. The antennae of moths are of various forms ; they are usually thread-like or feather- like ; only in rare cases are they enlarged towards the tip. The moths include all but the last six families of Lepidop- tera. The Skippers.— The skippers are so called on account of their peculiar mode of flight. They fly in the daytime and dart suddenly from place to place. When at rest they I96 THE STUDY OF INSECTS. usually hold the wings erect in a vertical position like butterflies; often the fore wings are thus held while the hind wings are extended horizontally. The antennae are thread-like, and enlarged towards the tip ; but in most cases the extreme tip is pointed and recurved, forming a hook. The abdomen is usually stout, resembling that of a moth rather than that of a butterfly. This division includes two families. The Butterflies. — The butterflies fly by day ; and when at rest they fold the wings together above the back in a vertical position. The antennae are thread-like with a club at the tip, which is ng^er recurved so as to form a hook. The abdomen is slender. This division includes the last four families described in this chapter. Classification of the Lepidoptera. (For Advanced Students.) The study of the classification of the Lepidoptera is beset by a peculiar difficulty. As these insects are clothed with scales com-- paratively little of their structure can be examined without injury to the specimens studied. Fortunately, however, it has been found that the various modifications of the framework of the wings afford excellent clues to the relationships of the different groups ; and these modifications can be determined in most cases without serious injury to the specimens. The structure of the antennae also can be easily studied, and in many cases affords much help in determining the zoo- logical position of an insect. The first step to be taken in the study of the classification of these insects is to become thoroughly familiar with the nomenclature of the wing veins ; this is given on pages 64 to 66. It is a good plan to take several of the larger moths and butterflies and make draw- ings showing the courses of the Veins of the wings in each, carefully indicating the names or numbers of the veins on the drawings. The making of such drawings will be of much use in fixing the ar- rangement of the veins in the student's mind. It should be remem- bered that veins IV and VI are not developed in this order. As the scales on the lower surface of the wings are more closely applied to the wings than are those on the upper surface, the veins can be best seen when the wings are examined from below. The LEPIDOP TERA . 1 97 veins can be rendered more distinct for a few seconds by putting a drop of chloroform on the part of the wing to be examined ; this can be easily done by means of a camel's-hair brush. Sometimes it is necessary to remove the scales from a small part of the wing in order to determine the nature of some characteristic; this can be easily done with an artist's sabie brush. A very small brush is best for this purpose ; and care should be taken not to break the wing. The above methods are all that are needed in the majority of cases where the mere determination of an insect is the object. But when a very careful study of the venation of a wing is to be made, it should be bleached and mounted on a card or on a glass slip in order that it may be studied with a compound microscope. The fol- lowing is the method of bleaching wings : — 1. Remove the wings carefully so as not to break the frenulum if there be one; it is well to remove the patagium first. 2. Dip the wings in alcohol in order to wet them. 3. Immerse them for an instant in hydrochloric acid (muriatic acid). Use for this purpose dilute acid, one part acid to nine parts water. 4. Put them in Labaraque solution with the upper surface of the wings down, and leave there till the color has been removed from the scales. If a wing bleaches slowly, the process can be hastened by dipping it in the dilute acid and returning it to the Labaraque solution from time to time. This solution can be procured of most druggists. It deteriorates if left exposed in strong sunlight. If it cannot be obtained, use an aqueous solution of chloride of lime. 5. When a wing is bleached put it in alcohol and leave it there till after it floats. This is to wash off the Labaraque solution. The wing can then be mounted on a card. But it is better to mount it as described below. 6. Transfer the wing to a clearing mixture, if it is to be mounted in balsam, and leave it there five or ten minutes. This is to remove any water there may be on it. A good clearing mixture can be made by mixing two parts by weight of carbolic:acid crystals and three parts of rectified oil of turpentine. 7. Put the wing on a glass slip with considerable clearing mixture under it to avoid bubbles ; put Canada balsam on top, and cover with thin glass. In the case of small wings, it is best to transfer them from one solution to another, and to the glass slip by means of a camel's-hair brush. Wings bleached and mounted in this way make an important i dition to a collection. The slides should be carefully labelled ; and 198 THE STUDY OF INSECTS. the insect from which the wings were taken should be kept with the slide. It is our practice to remove always the wings from the right side, and then to mount the slide in the collection at the right of the insect from which the wings were taken. Uniformity in this respect adds greatly to the appearance of the collection. The student should study his larger speci- mens first, leaving the 5 smaller ones till he has acquired skill in this work. There are a few spe- cial terms used in de- scribing the wings of the Lepidoptera which should be learned: — Frenulum. — In most moths there is a strong spine or a bunch of bristles borne by the hind wing at the hume- ral angle (Fig. 237, /); this is the frenulum. Its use is to insure the acting together of the two wings of one side. Except in the Microlepidoptera the frenulum of the male consists of a single strong spine; that of the female of two or more bristles. Jugum.— In one suborder, including only a few rare moths, ^ there exists, instead of a fren- ulum, a lobe borne near the base of the inner margin of the fore wing (Fig. 238,7); this is the jugum. See sub-order Jugatae. Discal Cell.— Near the cen- tre of the basal part of the VH, VH, wing there is a large cell lying FlG- 238.— Wings of Hepiaius gradlis. between veins III and VII (Fig. 239, d.c.); this is the discal cell, re generalized Lepidoptera this cell is divided into two by the base of vein V (Fig. 239, hind wing); in such cases the LEP1DOPTERA. 199 " JHiJ5!llnJ im cell lying immediately behind vein III is cell III, and that lying immediately behind vein V is cell V. Accessory Cells.— In many genera the branches of vein III of the fore wings anastomose so as to form one or more cells beyond the apex of the discal cells (Fig. 239, a.c.)\ these are the accessory cells. Discal Vein. — The cross vein at the outer end of the discal cell is termed the discal vein (Fig. 239, d.v.). Patagia. — At the base of each fore wing there is a scale-like ap- pendage; these are the patagia. The paiagia correspond to the tegulae of the Hymenoptera and the elytra of the Cole- optera. In descriptions of FIG. 239.— Wings of Notolophi Lepidoptera reference is often made to the palpi. These form the double beak-like projection which extends forward from the lower surface of the head. In most Lepidoptera only the labial palpi are well developed ; but in some of the more generalized forms the maxillary palpi are also present. The presence or absence of ocelli is a character which is sometimes of considerable importance. These or- gans are situated, one on each side, above the compound eye and near its margin (Fig. 240). But it requires some 24°posiUon of ocellus.8 ° * skill to find them when they are present, on account of the long scales clothing the head. The Phylogeny of the Lepidoptera. — Since the general acceptance of the theory of evolution — that is, the theory that the higher animals and plants have been developed from lower ones— it has become evi- dent that the only sure basis for classification is a knowledge of the 20O THE STUDY OF INSECTS. history of the various races of animals and plants, or phylogeny (phy- log'e-ny), as it is termed. The scope of this book has not permitted an extended treatment of this phase of the subject. There is space for only a few hints re- garding the phylogeny of the families of a single order; but these hints will serve as an illustration of a method of study. The Lepi- doptera is chosen for this purpose, as the method has been applied to this order more fully than it has to others. It is a well-known fact that every kind of animal and plant trans- mits a general likeness with individual differences to its offspring. According to the Darwinian theory of natural selection these dif- ferences or variations may be of any kind and in any direction. And as many more animals are born or plants germinated than can live to reach maturity, owing to the tendency of each kind to increase in a geometrical ratio, each individual is subjected to a severe struggle for existence. The result of this struggle is that any individual possessing a for- tunate variation — that is, one that enables it to get its living and escape its dangers more easily than its fellows — will be more apt on this account to reach maturity and propagate its kind than will less fortunate individuals. Thus there is a thinning-out process which tends to the production of more and more specialized forms of animals and plants, i.e., forms adapted to the special conditions under which they exist. It should be remembered that the difficulties surrounding exist- ence may be met in different ways; and that thus there may have descended from a common ancestor very different forms, each well fitted to meet the struggle for existence. See Chapter I, pp. r and 2. Just what changes have taken place in the structure of the mem- bers of any race is a difficult matter to determine, for, although many fossils have been found, the record is still very incomplete. But for- tunately something can be learned regarding this by the study of living animals. For not all members of the same family, or order, or class are equally specialized. Some retain more nearly than others the form of their remote ancestors ; and by the study of these general- ized forms, as they are termed, we can gain some idea of the struc- ture of the animals of past ages, and of the ways in which existing animals have been modified. We will state very briefly some of the conclusions that we have d regarding the phylogeny of the families of the Lepidoptera. These conclusions are based largely on a study of the wings. It is hoped that other parts will be studied in the same way ere long LEP1DOPTERA. 201 In the flight of insects it is important that the two wings of each side should act together, and we find that this is secured in most orders by uniting them in some way. In the Lepidoptera two dis- tinct methods are employed ; in some it is done by means of a. jugum, in others by means of a frenulum or its substitute. As neither the jugum nor the frenulum could be derived from the other, we infer that the primitive Lepidoptera possessed neither of these organs, but had wings that were quite distinct from each other. In the course of time there was developed in some of the descendants of these primi- tive forms a jugum ; while in others there was developed a frenulum. Of course in each case the development was a gradual one, extending through many generations. Thus the frenulum at first was probably merely a bunch of hairs like those elsewhere on the wings; but these became stiffer and stiffer in succeeding genera- tions. The descendants of those ancient Lepidoptera in which a jugum was developed constitute the suborder Jugatce ; while the descendants of those in which a frenulum was developed con- stitute the suborder Frenatcz. We know but little of the Jugatae, as nearly all of them have perished. There remain only two small families, the Hepialidse and the Microptery- gidae. But these families are very widely separated, and hence it is safe to assume that they are the remnants of what was in past times a large fauna. In the Frenatae, however, FlG 24, _ wings of Anaaandria. there exist to-day many families, each exhibiting its own methods of specialization. In some of these families the frenulum has been preserved and perfected to a greater or less extent. But in others a curious change has taken place. It is obvious that if the two wings of each side overlap to a gi extent, their acting together will be assured by this fact. And this is 202 THE STUDY OF INSECTS. what has taken place with the butterflies, the skippers, and certain moths With these insects the humeral angle of the hind wing has been greatly enlarged, so that it projects far beneath the fore wing (Fig 241). When this has taken place there is no longer any need of a frenulum, and consequently this organ is no longer preserved by natural selection. We find, therefore, that several families of Lepi- doptera that belong to the suborder Frenatse, being descendants of VIII FIG. 242. — Wings of Bombyx mori, ancient frenulum-bearing moths, no longer possess a frenulum. These are classed in the following synopsis as the frenulum-losers. It is a very interesting fact, and one that bears out the theory just stated, that in the more generalized of the frenulum-losing moths, as the Bombycidse, the frenulum has not yet entirely dis- appeared, but is preserved in a rudimentary state (Fig. 242). We place the frenulum-losers last in a serial arrangement of the fami- LEPIDOP TERA . 203 lies of Lepidoptera, regarding them as those that depart most widely from the primitive type. From the foregoing it will be seen that a study of the relation to each other of the fore and hind wings gives us important hints as to the probable courses development has taken in the different families. Equally suggestive hints may be derived from a study of the venation of the wings. By an extended study of fossil forms and the more generalized of living forms, the details of which study cannot be given here,* rt haa been determined that in the primitive Lepidoptera vein V of both fore and hind wings was well developed, and extended from the base of the wing out through the discal cell. We find that in certain families of existing moths this vein is still preserved (see p. 65), while in others it has been lost. Those families of the Frenatae in which it is best and most uniformly preserved are grouped together as the Generalized Frenatce (see the following synopsis), while those in which it is lost or nearly so are considered more specialized. With the loss of the base of vein V there occurs a connection of its branches with veins III and VII, so that in the more specialized forms these branches of vein V appear to be branches of those veins (Fig. 241). A study of the extent to which this change has gone gives much aid in determining the zoological position of the different genera and families. In certain families vein V2 tends to become united to vein III ; in others it tends to become united to vein VII. This too is anf important character, of which use is made in the following synopsis. The number of anal veins is another character the study of which throws much light on the relative position of the different forms. It has been determined that the ancient Lepidoptera had at least three anal veins in both fore and hind wings. This number has been pre- served in one or both pairs of wings of the more generalized of living moths, but has been reduced to two or even to one in the more specialized families. Enough has been said, without going into. further details here, to show that the way to determine the relationships of organized beings is to determine the primitive form of their organs and the changes that have been brought about in these organs by the action of natural * The data upon which these conclusions are based are given at greater length in an essay, by the senior author, entitled Evolution and Taxonomy. This essay forms a part of the Wilder Quarter-Century Book, publis the Comstock Publishing Company, Ithaca, N. Y. 204 THE STUDY OF INSECTS. selection. The classification of animals and plants should not be merely the assorting of them into convenient pigeon-holes, but a serious study of their blood-relationships. The following synopsis will serve to show what we believe to be the relations of the principal divisions of the order. Following this synopsis there is a table for use in classifying specimens. SYNOPSIS OF THE LEPIDOPTERA. (See page 207 for a table for determining specimens.') A. THE JUGATE LEPIDOPTERA. — Moths in which the two wings of each side are united by &jugnm (Fig. 238, /), p. 214. Suborder JUGAT/E. B. The Swifts or Macrojugatce, p. 215 Family HEPIALID/E. BB. The Little-wing Jugates or Microjugatce, p. 216. Family MICROPTERYGID^E. AA. THE FRENATE LEPIDOPTERA.— Moths, skippers, and butterflies in which the two wings of each side are united by Sifrenitlum (Fig. 237. /) or by its substitute, a large humeral angle of the hind wing (Fig. 241), p. 216 Suborder FRENAT^E. B. THE GENERALIZED FRENAT^E. — Moths that are supposed to retain more nearly than any other Frenatse the form of the primi- tive Frenatae, those that were the first to appear on earth. In these generalized moths the wings approach the"' typical form ; the base of vein V of one or both pairs of wings is preserved throughout a considerable part at least of the discal cell ; and the anal veins are well preserved, there being two or three in the fore wing and three in the hind wing. The frenulum is usually well preserved. The Flannel-moths, p. 218 Family MEGALOPYGID^E. The Bag-worm Moths, p. 219 Family PSYCHID^E. Carpenter-moths, p. 221 Family COSSID^E. The Slug-caterpillar Moths, p. 223 Family EUCLEID^E. The Smoky-moths, p. 226 Family PYROMORPHID^. THE SPECIALIZED FRENATAJ.— Moths, skippers, and butter- that depart more widely than do the Generalized Prenatal 3m the primitive type of Lepidoptera, being more highly modi- >r special conditions of existence. An indication of the iciahzed condition of these insects is the modified form of the In nearly all the base of vein V has been lost and the branches of this vein joined to veins III and VII. LEPIDOPTERA. 205 C. THE MICRO FRENAIVE. — Frenulum-bearing moths, which are usually of small, often minute, size. The anal area of the hind wings is not reduced, having usually three anal veins except in certain minute forms where a broad fringe has been substituted for the membrane of this area. The Pyralids, p. 228 Superfamily PYRALIDINA. The Tortricids, p. 239 Superfamily TORTRICINA. The Tineids, p. 246 Superfamily TINEINA. The Clear-winged Moths, p. 259 Family SESIID/E. CC. THE SPECIALIZED MACROFRENAT^E.— Specialized Frenatae which are usually of medium or large size. This division includes certain moths and all skippers and butterflies. In these insects the anal area of the hind wing is reduced, con- taining only one or two anal veins. D. The Frenulum-conservers. — Specialized Macrofrenatae in which the two wings of each side are united by a frenulum. This group includes only moths. E. Moths that appear to have a three- branched cubitus, only vein V» being closely connected with vein VII. Vein V« either retains its primitive position midway between veins III and VII or arises from the discal vein nearer to vein III than to vein VII * The Dioptids, p. 262 Family DIOPTID*:. The Prominents, p. 263 Family NOTODONTIDJE. The Measuring-worm Moths, p. 270. Superfamily GEOMETRINA. EE. Moths that appear to have a four-branched cubitus, the base of vein Va of one or both pairs of wings being more closely connected with vein VII than with vein III. F. Moths in which the humeral angle of the hind wings is greatly extended, but which as a rule possess the frenulum in one sex at least. The Auzatids, p. 288 Family AUZATID.*. The Hook- tip Moths, p. 289. ..... .Family DREPANIDVE. FF. Moths in which the humeral angle of the hind wings is not greatly extended. G. The Noctuids and their Allies.— Moths in which some of the branches of vein III of the fore wings coalesce * In many Hawk-moths'vehTv, nearly or quite retains its primitive position ; but when it has moved from this position, it is nearer to vein than to vein III. This family is placed, therefore, in the next d of this synopsis. 206 THE STUDY OF INSECTS. beyond the discal cell, and which do not have what appears to be a cross vein between veins II and III of the hind wings. The Cymatophorids, p. 291 .Family CYMATOPHORID^E. The Owlet-moths, p. 293 Family NOCTUIDJE. The Tussock-moths, p. 308 Family LYMANTRIID./E. The Wood-nymph Moths, p. 313. Family AGARISTID/E. The Pericopids, p. 316 Family PERICOPID^E. The Tiger-moths, p. 317 Family ARCTIID^:. The Footman-moths, p. 324 Family LITHOSIID^;. The Zygaenids, p. 326 Family ZYG^NlDiE. GG. The Window-winged Moths.— Moths in which vein III of the fore wings is five-branched and in which all of these branches arise from the discal cell (Fig. 404), p. 328 Family THYRIDID^E. GGG. The Hawk-moths. — Moths in which there appears to be a cross vein between veins II and III of the hind wings (Fig. 407), p. 329 Family SPHINGID^E. DD. The Frenulum-losers. —Specialized Macrofrenatae, in which the frenulum has been supplanted by a greatly extended humeral area of the hind wings. In some of the more gen- eralized forms a rudimentary frenulum persists (Bornbycidae and Lacosomidae). This division includes three groups of families: the Frenulum-losing Moths, the Skippers, and the Butterflies. The grouping together of the families included in this division is merely provisional, as it is probable that the loss of the frenulum has arisen independently in several of them. E. The Frenulum-losing Moths. — In these moths the antennae are usually pectinate ; they are never enlarged into a club at the tip. F. Moths with cubitus of the fore wings apparently three- branched. G. Moths in which veins Ills and III4 coalesce to a great extent. The Saturnians. p. 339. Superfamily SATURNIINA. GG. Moths in which veins III, and III« do not coalesce beyond the discal cell. p. 357. .Family LACOSOMIDJE. FF. Moths in which cubitus of the fore wings is apparently four-branched, p. 359 Family LASIOCAMPID^;. EE. 'The Skippers. — These are day-flying Lepidoptera which resemble butterflies in usually holding their wings erect LEPIDOPTERA. 2O/ when at rest, but are distinguished by the peculiar venation of the fore wings, vein III being five-branched, and all the branches arising from the discal cell. The antennae are enlarged into a club towards the tip. p. 364. Superfamily HESPERIINA. EEE. The Butterflies.— Day-flying Lepidoptera that hold their wings erect when at rest, that have clubbed antennae, and that differ from the Skippers in the venation of the fore wings, some of the branches of vein III coalescing beyond the discal cell Superfamily PAPILIONINA. F. Butterflies in which vein VII is apparently four- branched. The Swallow-tail Butterflies, p. 375. Family PAPILIONID/E. FF. Butterflies in which vein VII is apparently three- branched. G. Butterflies exhibiting no tendency to abortion of the fore legs. The Pierids. p. 381 Family PIERID^E. GG. Butterflies exhibiting a marked tendency to abor- tion of the fore legs. The Gossamer-winged Butterflies, p. 388. Family LYC;ENID/E. The Brush-footed Butterflies, p. 395. Family NYMPHALIDJE. TABLE FOR DETERMINING THE PRINCIPAL GROUPS OF LEPIDOPTERA. A. Wingless or with rudimentary wings. This division includes only females. All males of Lepidoptera are winged. B. The larvae case-bearers; the adult female remaining within the case to lay her eggs. p. 219 PSYCHID^E. BB. The larvae not case-bearers ; the wingless adult not in a case. C. The adult remaining upon her cocoon to lay her eggs; the body of the adult clothed with fine hairs, p. 308. LYMANTRIID/E. CC. The adult active, laying her eggs remote from her cocoon; the body of the adult clothed with flattened scales, p. 270. GEOMETRINA. AA. Winged, fore and hind wings similar in form and venation, the radius of the hind wings being, like that of the fore wings, five- branched. (Fig. 238.) (Suborder Jugate^ [See also A A A.] 208 THE STUDY OF INSECTS. B. Moths of medium or large size. p. 215 HEPIALID^:. BB. Minute moths, resembling Tineids in appearance, p. 214. MlCROPTERYGID^E. AAA. Winged, fore and hind wings differing in form and venation ; the radius of the hind wings being simple, although frequently apparently two- or three-branched ; this is due to the union of one or two branches of media with it (Figs. 241, 242). (Suborder Prenatal) B. Antennae of various forms, but never thread-like with a knob at the extremity* (moths in part). C. The fringe on the inner angle of the hind wings as long as, or longer than, the width of the wing; the hind wings often lanceolate, but never fissured, p. 246 TINEINA. CC. The fringe on the hind wings shorter ; the hind wings not lanceolate. D. Wings fissured. E. Each wing divided into six lobes, p. 238. ..ORNEODID^E. EE. Wings never more than four-lobed ; usually the fore wings are bilobed and the hind wings trilobed. p. 237. PTEROPHORIDA;. DD. Wings not fissured. E. Fore wings very narrow, the width at the middle less than one fourth the length of the wing ; a considerable part of the hind wings, and in many cases of the fore wings also, free from scales, p. 259 SESIID^. EE. Wings scaled throughout, or if clear with the fore wings triangular in outline. F. Hind wings with three anal veins. Care must be taken not to mistake a mere fold in the wing for a vein. When there is no thickening of the membrane of the wing along a fold it is not counted as a vein. G. Subcosta and radius of the hind wings grown together for a greater or less distance between the apex of the discal cell and the apex of the wing, or in some cases separate but very closely parallel, p. 228..PYRALIDINA. GG. Subcosta and radius of the hind wings widely sep- ^ arate beyond the apex of the discal cell. * In some moths the antennae are enlarged towards the tip, forming a more or less distinct club ; but this club is quite different in shape from the knob at the extremity of the antennae in the skippers and the butterflies. In the moths with club-like antennae the ocelli are usually present, and the hind wings bear a frenulum. LEPIDOPTERA. 2., with a large abdomen and with rather narrow, strong, and coarsely-scaled fore wings. M. Vein Vs of the hind wings arising much nearer to cubitus than to radius; vein Vi of the hind wings joined to radius at a considerable distance before the apex of the discal cell (Fig. 349). p. 291. CYMATOPHORID.E. MM. Vein Vs of the hind wings either wanting or present, but when present arising either midway between radius and cubitus. or nearer to radius than to cubitus; vein V, of the hind wings joined to radius at or beyond the apex of the discal cell (Fig 311). p. 263. NOTODONTID^. LL. The basal part of the subcosta of the hind wings joined to radius for a consider- able distance and then making a prominent bend towards the costal margin, as in Cicirt- 212 T3E STUDY OF INSECTS. nus (Fig. 438). Veins Ills and III4 of the fore wings separate from each other, p. 357. [See also LLL.] LACOSOMID^E. LLL. The basal part of the subcosta of the hind wings making a prominent bend into the humeral angle of the wing (Fig. 327); veins Ills and lilt coalesced to near the apex of the wing. In most cases, moths with a slender abdomen, and with rather broad, delicate wings, which are finely scaled, p. 270 GEOMETRINA. KK. Vein Va of the fore wings more closely joined to cubitus than to radius ; cubitus be- ing in most cases apparently four-branched. L. Small moths with the apex of the fore wings sickle-shaped, p. 289. .DREPANID^E. LL. Apex of the fore wings not sickle-shaped. M. Small moths with snow-white wings, in which the subcosta of the hind wings ex- tends distinct from radius to a point be- yond the discal cell where the two are united for a greater or less distance (Fig. 344). p. 288 AUZATID^E. MM. The subcosta of the hind wings ex- tending distinct from the radius, or the two joined for a very short distance, near the base of the wing. [See also MM M.J N. Chiefly day-flying moths that are either black with large, white or yellow, rounded patches upon the wings, or have the front wings white, margined with brown, and the hind wings pale yellow. O. Cubitus of hind wings apparently four-branched (Fig. 384). p. 316. PERICOPID^E. OO. Cubitus of hind wings apparently three-branched (Fig. 379). p. 313. AGARISTIDJE. NN. Not such moths as are described under N. O, Antennae pectinate. LEPIDOPTERA. 21$ P. Ocelli absent, p. 308. LYMANTRIID>E. PP. Ocelli present, p. 293 NOCTUID^E. OO. Antennae simple, p. 293. NOCTUID^E. MMM. The subcosta of the hind wings united with the radius for a considerable distance (i.e., for one fifth or more of the length of the discal cell). N. The subcosta and radius of the hind wings united for a considerable distance, but usually separating before the apex of the discal cell. O. Ocelli present, p. 317. ..ARCTIIDJE. ^ OO. Ocelli absent, p. 324..LiTHOSHDyE. NN. The subcosta and radius of the hind wings united into a single vein (Fig. 399), or at most with their tips separate near the apex of the wing. With all the moths included under this head and under the preceding N, vein V, of the hind wings is present and is joined to radius at or near the apex of the discal cell ; care should be taken not to mistake this vein V, for radius, p. 326 ZYG^NID^:. HH. Frenulum absent ; the humeral angle of the hind wings largely expanded and serving as a substitute for a frenulum. I. Cubitus of both wings apparently four-branched, due to the fact that both the second and third branches of media (V2 and V3) are joined to it. J. Small moths, with slender bodies, and with the apex of the fore wings sickle-shaped ; humeral veins absent, p. 289 DREPANIDJE. JJ. Moths of various sizes, but with robust bodies, and with the apex of the fore wings not sickle- shaped ; hind wings with humeral veins, p. 359 LASIOCAMPIDjE. II. Cubitus of both fore and hind wings apparently three-branched, due to the fact that only the third branch of media (V3) is more closely joined to it than to radius. (The moths included in this 214 THE STUDY OF INSECTS. section of this table are robust, with strong wings, and are of medium or large size. In some of the Geometrina (p. 270), which also have a three- branched cubitus, the frenulum is inconspicuous or even in rare cases (Dyspteris) wanting ; these moths can be distinguished from those included here by their smaller size, more slender body, and weaker wings), p. 339 SATURNIINA. BB. Antennae thread-like with a knob at the extremity. C. With the radius of the fore wings five-branched, and with all of the branches arising from the discal cell (Fig. 445) ; club of antennae usually terminated by a recurved hook. The Skip- pers, p. 364 HESPERIINA. CC. With some of the branches of the radius of the fore wings coalesced beyond the apex of the discal cell (Fig. 455) ; club of antennae not terminated by a recurved hook. The Butterflies. p. 373 PAPILIONINA. Suborder JUGATE (Ju-ga'tae). The jugate (Ju'gate] Lepidoptera. The American representatives of this suborder are rare moths, which the student beginning the study of insects is not likely to meet. They can be easily recognized by the peculiar structure of the hind wings, which resemble the fore wings in form and in venation (Fig. 238). In all other Lepidoptera, the two pairs of wings differ in form, and the hind wings are furnished with fewer veins than are the fore wings. The most important characteristic of the sub- order, and the one to which its name refers, is the way in which the two wings of each side are fastened together. There projects backward from the inner margin of the fore LEPIDOPTERA. 215 wing near its base a small lobe (Fig. 243,^'), which extends under the costal margin of the hind wing; while the greater part of the inner margin of the fore wing overlaps the hind wing. This arrangement assures the acting together of the two wings. This projecting lobe is named thefugum or yoke ; and the moths possessing this organ are termed the Jugatae or the Jugate Lepidoptera. This suborder includes only two families; one represented by minute moths, the other by moths of medium or large size. Family HEPIALID^E (He-pi-al'i-dae). The Swifts. The members of this family are of medium or large size. Figure 244 represents one of the larger species. Our best FIG. ztA.—Hepialus argcnteomacvlattu. known forms are brown or ashy gray in color, with the wings marked with silvery white spots. It is said that these moths fly near the earth, and only in the evening after sunset, hiding under some low plant, or clinging to the stalk of an herb during the day. Some of them fly with extreme rapidity, with an irregular mazy flight, and have, therefore, been named Swifts by collectors. They are attracted to lights. Figure 238 represents the venation of the wings of Hepialus (He-pi'a-lus). 216 THE STUDY OF INSECTS. The larvae are nearly naked, and grub-like in appearance, although furnished with sixteen legs. They feed upon wood, and are found at the roots or within the stems of plants. They transform either in their burrows, or, in the case of those that feed outside of roots, within loose cocoons. The pupae have transverse rows of teeth on the abdominal seg- ments ; these aid them in emerging from their burrows. The best known American species bores in the stems of the speckled or hoary alder (Alnus incand). Family MICROPTERYGID^E (Mi-crop-te-ryg'i-dae). The Little-winged Jugates (Ju' gates). These are very minute moths, which resemble Tineids in size and appearance. The largest species known to the writer expands but little more than half an inch. Figure 245 represents the venation of the wings. Only a single genus, vni vnaVIIi FIG. 245.— Wings of Micropteryx. Micropteryx (Mi-crop'te-ryx), occurs in this country. The larvae are leaf-miners. Suborder FRENAT^; (Fre-na'tse). The Frenate (Fre'nate) Lepidoptera. To the Frenatae belong nearly all of our moths, and all skippers and butterflies. With most moths of this suborder LEPIDOPTERA. 21 7 there exists near the base of the costal margin of the hind wings a strong bristle or bunch of bristles named the frenu- lum, or little bridle (Fig. 237, /). As the frenulum projects forward under the fore wing it tends to depress the hind wing when the fore wing is depressed, thus insuring the act- ing together of the twro pairs of wings. Usually the frenulum consists of two or more bristles in females and of a single stronger bristle in males. The difference is due to the fact that in males the bunch of bristles have grown together into a single strong bristle. There is also another sexual differ- ence. In the males the tip of the frenulum fits into a mem- branous hook borne on the lower surface of the fore wing, thus firmly tying together the two wings (Fig. 237, f.li). This frenulum hook is rarely found in females. In certain moths there is, besides the frenulum hook, a tuft of hairs projecting forwards from just behind the cubitus of the fore wing near its base, which tends also to keep the frenulum in place. With some moths and with all skippers and all butterflies the base of the costal portion of the hind wings, the humeral angle as it is termed, is largely developed, so that it projects far under the fore wing (Fig. 241). This overlapping of the two wings at the base to so great an extent insures their act- ing together without the aid of the frenulum ; and, conse- quently, there being no use for a frenulum, this organ has disappeared. In other words, the frenulum has been super- seded by the large development of the humeral angle. But as we believe that these moths, skippers, and butterflies have descended from forms which had a frenulum, we class them with the moths that still possess this organ under the sub- order Frenatae. A more easily observed character which serves to distin- guish members of this suborder is a striking difference in the venation of the two pairs of wings, the hind wings hav- ing fewer veins than the fore wings. 218 THE STUDY OF INSECTS. Family MEGALOPYGID^: (Me-gal-o-pyg'i-dse). The Flannel-moths. Sometimes there is attracted to our evening lamp a whitish moth, whose wings, being densely clothed with long curly hairs, resemble bits of flannel ; this is the Crinkled Flannel-moth, Megalopyge cris- pata (Me-gal-o-py'ge cris-pa'ta). It is cream-colored, with the fore wings marked with wavy lines of crinkled black and brownish hairs. The male is represented by Fig- ure 246 ; the female is larger, FIG. 246— Megalopyge crispata. expanding one and three fifths inches. In the female the antennae are very narrowly pecti- nate. The larva is said to feed on oak, elm, apple, and rasp- berry. In the Southern States there occur three other species of this family. These moths are easily distin- guished by the structure of their wings (Fig. 247). There are three anal veins in both fore and hind wings ; but in the fore wings the second and third anal veins (veins IX and XI) are partially grown together. The basal part of vein V is more or less distinctly preserved, and divides the discal cell into two nearly equal parts. Veins II and III of the hind ix vni Wings are grown tO- FlG< 247-~ Win&s of Megalopyge crispata. gether nearly to the end of the discal cell. LEPIDOPTERA. 219 The larvae of the Flannel-moths are remarkable for the possession of ten pairs of legs, three thoracic and seven abdomi- nal. All other known lepidopter- ous larvae, except perhaps those of Micropteryx, have lost some of the abdominal legs. The cocoons of these insects are also remark- FIG. 248.-Cocoon of . able, being furnished with a trap-door (Fig. 248). Family PSYCHID^E (Psy'chi-dae). The Bag-worm Moths. The Bag-worms are those caterpillars that have the curi- ous habit of building each for itself a silken sac covered with little twigs within which it lives (Figs. 249 and 250). When the caterpillar wishes to move from one place to another it pushes forth the front end of its body and creeps along, carrying its house with it. It is said that the species that inhabit Ceylon are be- lieved by the natives to be composed of individuals who in a previous incarnation were human beings and stole kindling-wood, and who now atone for the theft by repeat- ing the act as an insect. When a Bag-worm is fully grown, it fastens its sac to a twig and changes to a pupa within it. And here the females remain until death, leaving their eggs within their sacs. These females are grub- like creatures without wings. But the male pupa works his way out from the lower end of his sac and changes to a winged moth. Figure 250 rep- resents the sac of a male with the empty pupa-skin projecting FIG. 249.— Bag of Oiketicus abbotii. emales 4 FIG. 250. -Bag of FIG. 251 — Psyt confederatn. 220 THE STUDY OF INSECTS. FIG. v&.—Tkyridopttryx tphemirtfformis. from the lower end, and Figure 251 the fully developed male. These figures are of one of our smaller species, which belong to the genus Psyche (Psy'che). Abbot's Bag-worm, Oikettcus abbotii (Oi-ket'i-cus ab- bot'i-i). — This species occurs in the more southern part of our country. The larva makes a bag with sticks attached to it crosswise (Fig. 249). The Evergreen Bag-worm, TJiyridopteryx epJiemercufor- mis (Thyr-i-dop'te-ryx e-phem-e-rae-for'- mis). — This is our best known species, and on this account has been commonly called The Bag-worm. But as it is desir- able to have different names for the dif- ferent species, we call this one the Ever- green Bag-worm ; for although it feeds on many different trees, it prefers red cedar and arbor vitae. The bag of this species is about the same size as that of Abbot's Bag-worm; but it dif- fers in being covered with bits of leaves of cedar or arbor vitae, or with twigs attached lengthwise. The structure of the wings of the Psy- chidae is very char- acteristic (Fig. 253). Both the fore and the hind wings may have either two or FIG. FIG. 53-— Wings of Thyridopteryx ephetntratforntis. three anal veins ; but the anal veins of the fore wings are grown together so as to ap- pear as a single much-branched vein. The base of vein V is preserved and is forked LEPIDOPTERA. 221 within the discal cell. In the hind wings, veins I and II and veins II and III are grown together in an unusual way. In Figure 254 these veins are represented slightly separated in order to show their relation to each other. Family CossiDJi (Cos'si-dae). The Carpenter-moths. This family includes moths with spindle-shaped bodies, and narrow, strong wings, some of the species resembling Hawk-moths quite closely in this respect. The larvae are wood-borers, living in the solid wood of the trunks of trees. They are often very injurious to forest or shade trees, and one recently imported species is very injurious to pear trees. The wood-boring habits of the larvae suggest the popular name Carpenter-moths for the insects of this family. These moths fly by night, and lay their eggs on the bark FIG. 255.— Wings of Prionoxytus robinia . /, frenulum, enlarged. of trees, or within tunnels in trees from which adult Car- penter-moths have emerged. The caterpillars are nearly naked, and, although furnished with pro-legs as well as true legs, are grub-like in form. The pupa state is passed within 222 THE STUDY OF INSECTS. the burrow made by the larva. When ready to change to an adult, the pupa works its way partially out from its bur- row. This is accomplished by means of backward-project- ing, saw-like teeth, there being one or two rows of these on each abdominal segment. After the moths have emerged the empty pupa-skins can be found projecting from the deserted burrows. The Carpenter-moths are of medium or large size. Our more common species are of a pepper-and-salt color, due to strongly contrasting dark and light scales. The antennae are usually pectinate in both sexes, but in some species those of the female are simple ; the ocelli are wanting ; and the mouth-parts are obsolete. The structure of the wings is shown in Figure 255 There are two anal veins in the fore wing, and three in the hind wings. The base of vein V is preserved, and is forked within the discal cell. In the fore wings, the branches of vein III anastomose so as to form an accessory cell. The frenulum is rudimentary in most of our genera (Fig. 255), but is strongly developed in others. Our most common species is the Locust-tree Carpenter- FIG. z^.—Prionoxystus robinia. moth, Prionoxystus robinia (Pri-on-ox-ys'tus ro-bin'i-ae). Figure 256 represents the female natural size. The male is but little more than half as large as the female. It is much LEPID OP TERA . 223 darker than the female, from which it differs also in having a large yellow spot, which nearly covers the outer half of the hind wings. This species flies in June and July. As sug- gested by its name, it infests locust ; but its larva also bores in the trunks of oak, poplar, willow, and other trees. It is supposed that the species requires three years to com- plete its transformations. The Leopard -moth, Zeuzera pyrina (Zeu-ze'ra py-ri'na) is a large European species which has become common in the vicinity of New York City, and will doubtless spread to other parts of the country. It is white, spotted with numer- ous small black spots. Its larva is very injurious, especially to maple. It infests other shade trees, and also apple and pear. Family EUCLEID^: (Eu-cle'i-dae). The Slug-caterpillar Moths. One often finds on the leaves of shrubs or trees elliptical or oval larvae that resemble slugs in the form of the body and in their gliding motion. As these are larvae of moths they have been termed Slug-caterpillars ; but they present very little similarity in form to other caterpillars. The re- semblance to slugs is greatly increased by the fact that the FIG. 257.— Larva of Eulimacodes scapha. FIG. v$.—Euclta. delphinii, larva. FIG. 259. lower surface of the body is closely applied to the object upon which the larva is creeping, the pro-legs being replaced by mere swellings on the abdominal segments. Some species are naked (Fig. 257); but many of them are armed 224 THE STUDY OF INSECTS. with branching spines (Fig. 258). The larvae when full grown spin very dense cocoons of brown silk ; these are egg-shaped or nearly spherical (Fig. 259), and are usually spun between leaves. The moths are of medium or small size ; they vary greatly in appearance, and many of them are very prettily colored. Considerable variation exists in the venation of the wings in this family (Figs. 260, 261). The base of vein V may be preserved or wanting. In some species it is forked within the discal cell, in others not. There is also considerable variation in the coalescence of the branches of radius, but veins III3 and III4 co- alesce to a greater ex- tent than any other branches of this vein, and there is no accessory cell. The Skiff Caterpillar, Eulimacodes scaplia (Eu-lim-a-co'des sca'pha). — This remarkable larva (Fig. 257) is not uncommon on oak and other forest trees. It is pale apple-green, with a chestnut-brown patch on its back. The moth (Fig. 262) is light cinnamon-brown, with a tan-brown triangular spot on each fore wing. The Spiny Oak-slug, Euclea delphinii (Eu'cle-a del- phin'i-i). — This larva (Fig. 258) is one of the most common of our slug-caterpillars. It feeds on the leaves of oak, pear, willow, and other trees. The moth is cinnamon- brown, with a variable number of bright green spots on the fore wings (Fig. 263). VIII FIG. 260.— Wings of Adoneta sfinuloides. LEPIDOPTERA. 22$ The Saddle-back Caterpillar, Empretia stimulea (Em- pre'ti-a sti-mu'le-a).— This larva can be recognized by Fig- ure 264. Its most characteristic feature is a large gree^n XI vn, vii, IX ~~ VIII FIG. 261. — Wings of Packardia geminata. patch on the back, resembling a saddle-cloth, while the saddle is represented by an oval purplish-brown spot. The moth is dark, velvety, reddish brown, with two golden dots FIG. ite.—Eulimacodes scafha. FIG. z6^.—Euclea delphiitii. FIG. 264.— Emfirttia. stimulea, larva. near the apex of the fore wings. The larva feeds on oak and other forest trees. The prick of its spines is said to be venomous. 226 THE STUDY OF INSECTS. Family PYROMORPHID^E (Pyr-o-mor'phi-dae). The Smoky-moths. There are but few insects in our country pertaining to this family. These are small moths, that are chiefly of a smoky black color; some are marked with brighter colors. FM ^faharlul'. A tiny representative of the family which seems to be not uncommon in the East is Acoloitkus fal- sarius (Ac-o-loi'thus fal-sa'ri-us). This moth (Fig. 265) expands two thirds of an inch. It is black, with the pro- thorax of an orange color. The venation of its wings (Fig. 266) is peculiar in that subcosta and radius of the hind wings coalesce for only a short distance beyond the mid- dle of the discal cell, and a stump of radius pro- jects towards the base of the wing, from the point of union of the two veins. The larva feeds in early summer on the leaves of grape and of the Virginia creeper. It is said that the pupa state lasts fourteen days vn, IX VIII FIG. 266. — Wings of and is passed within a parchment-like cocoon. The adult frequents flowers in the daytime. The typical genus of the family is represented in the At- lantic and Western States by Pyromorpha dimidiata (Pyr-o- mor'pha di-mid-i-a'ta). The entire insect is smoky black, :cept the basal half of the fore wings in front of vein IX, basal half of the costa of the hind wings, which are 3w. The wings are thinly scaled, and expand a little than one inch. Figure 267 represents the venation of the wings. LEP1DOPTERA. 227 In Texas and Arizona there occur several species of Triprocris (Trip'ro-cris). The venation of one of them is shown in Figure 268. It is remarkable in that none of the branches of radius of the fore wings coalesce beyond the dis- cal cell. The genus Harrisina (Har-ris'i-na) seems to be closely allied to the preceding and is placed in this family provision- ally. It differs, how- ever, from the typical form of the family in that the anal area Of FlG- 267.— Wings of Pyromorpha dimidiata. the hind wings is greatly reduced, there being only two, short, strongly curved anal veins. As in the other members of the family there are J11* two,well-developed anal I111* veins preserved in the fore wings. In the East the most common species is Har- risina americana (H. a-mer-i-ca'na) (Fig. 269). VII, tt, FIG. 268.- Wings of Trifrocris marteni. FIG. a6g.—f/arrftfiia amtricana. The wings are long and narrow; the abdomen is long and widened towards the caudal end. It is greenish black in color, with the prothorax reddish orange. The larva feeds 228 THE STUD Y OF INSECTS. on the leaves of grape and of the Virginia creeper. An entire brood of these larvae will feed side by side on a single leaf while young. Harrisina texana (H. tex-a'na) occurs in the Southwest. It closely resembles the preceding; but is bluish black with a reddish orange prothorax. Harrisina coracina (H. cor-a-ci'na) also occurs in the Southwest. This species is entirely black. Superfamily PYRALIDINA (Pyr-a-li-di'na). The Pyralids (Pyr'a-lids\ This superfamily includes moths of medium or small size ; but so large a proportion of the species are small that the superfamily is commonly classed with the two following as Microlepidoptera. The members of the different families included in this superfamily differ so greatly in appearance that it is not possible to give a gen- eral description that will serve to distinguish it. It is necessary to study structural char- acters to find evidences of a common bond, and here as in other groups we find the structure of the wings most useful for this purpose. As a rule there are FIG. 270.— hind wings and two in the fore wings. In this respect this superfamily agrees with the preceding families and with the two following superfamilies. But in most cases the Pyralids can be recognized by the fact that the subcosta and radius of the hind wings are separate along the discal cell, but grown it, iir} in3 ll — LEPIDOPTERA. 229 vS* VIII FIG. 271.— Wings of Tlascala redttctelia. together for a short distance beyond the cell, after which they are again separate (Fig. 270). In some gen- era these two veins do not actually coalesce, but extend very near to- gether for a short dis- tance (Fig. 271). The two types, however, are essentially the same. This superfamily in- cludes seven families, which can be separated by the table given below. The Plume -moths are placed last in the series, as we believe that they depart more widely from the primitive type than do any of the other families. A. Wings not fissured. B. Hind wings without a fringe of hairs on the basal part of vein VII. Care must be taken not to mistake scattered hairs on the anal area of the wing for such a fringe. C. Fore wings with veins III4 and III5 separate, vein III* arising from the discal cell (Fig. 272). p. 230 PYRAUSTID*:. CC. Fore wings with veins IIL and Ills united at base (Fig. 277). p. 232 PYRALIDID^:. BB. Hind wings with a fringe of long hairs on the basal part of vein VII. C. Radius of fore wings five-branched. D. Maxillary palpi more or less developed, but not triangular as in the next family, p. 233 GALLERIID^:. DD. Labial palpi long, straight, projecting forward ; maxillary palpi well developed, strongly dilated at tip with scales, ap- pearing triangular when viewed from the side. p. 234. CRAMBIDiE. CC. Radius of fore wings four-branched, veins IIIi and III4 coalescing to edge of wing (Fig. 281). p. 235 PHYCITID*:. 230 THE STUDY OF INSECTS. AA. Wings fissured. B. Wings with less than five fissures; usually the fore wings have one fissure and the hind wings two. p. 237 PTEROPHORIDJE. BB. Each wing split into six parts, p. 238 ORNEODID^E. Family PYRAUSTID^; (Py-raus'ti-dse). The Pyraustids (Py-raus'tids). The members of this family differ from other Pyralids by the following combination of characters. There is no fringe of long hairs on the basal part of vein VII of the hind wings, and vein IIIB of the fore wings arises from the discal cell dis- tinct from vein III4 (Fig. 272). This family in- cludes many small moths; but it contains also the majority of the larger species of Pyra- lids. Some of the species are very striking in ap- pearance. The Grape Leaf- folder, Desntia fnneralis (Des'mi-a fu-ne-ra'lis) is a common species, the larva of which feeds on the leaves of grape. The larva folds the leaf by fastening two portions together by silken threads. When full grown, it changes to a pupa within the folded leaf. The moth is black with shining white spots. The male (Fig. 273) differs from the fe- male in having a knot-like enlargement near the middle of each antenna. There is some variation in the size and shape of the white spots on the wings. In some specimens the white spot of the hind wing is sepa- rated into two or three spots. FIG. 272. -Wings of Nomophila FIG. 273 — Desmia Juneralis. LEPIDOPTERA. 231 The Bass-wood Leaf-roller, Pantographa limata (Pan- tog'ra-pha li-ma'ta). — Our bass-wood trees often present a strange ap- pearance from the fact that nearly every leaf is cut more than half way across the middle, and the end rolled into a tube (Fig. 274). Within this tube there lives a bright green larva, with the head and thoracic shield black. This larva resembles cer- tain Tortricid larvae, both in ap- pearance and habits ; but a study of the adult shows it to be a Py- FIG. 274.— Nest of larva of Pantographa ralid. The moth expands about one and one half inches; it is straw-colored, with many elaborate markings of olive with a purplish iridescence (Fig. 275). There is one brood a year ; the winter is passed in the larval state. The Melon-worm, Margaronia hyalinata (Mar-ga-ro'ni-a hy-a-li-na'ta).— This beautiful moth (Fig. 276) is often a serious pest in our southern states, where the larva is very 232 THE STUDY OF INSECTS. destructive to melons and other allied plants, destroying both the foliage and the fruit. The moth is a superb FIG. ^.-Margaronia. hyalinata, larvae, cocoon, and adults. (From the Author's Report for 1879.) creature, with glistening white wings bordered with black, and with a spreading brush of long scales at the end of the abdomen. Family PYRALIDID.E (Pyr-a-lid'i-dae). The Typical Pyralids (Pyr'a-lids). The moths of this family are distinguished from other Pyr- alids, except the next family, by the absence of a fringe of hairs on the basal part of vein VII of the hind wings ; and they are distinguished from that family by the fact that veins IIIt and III, of the fore wings are united at base (Fig. 277). It is one of the smaller of the families of Pyralids ; fifty-four species are now enumerated in our lists. LEPIDOPTEKA. 233 The Meal-moth, Pyralis farinalis (Pyr'a-lis far-i-na'lis) is a common species. The larva feeds on meal, flour, and old clover-hay. The moth is commonly found near the food of the larva, but is often seen on the ceilings of rooms sitting with its tail curved over its back. It expands about an inch ; the fore wings are light brown, crossed by two curved white lines, and with a dark chocolate-brown spot on the base and tip of each. The Clover-hay Worm, Pyralis costalis (Pyr'a-lis cos-ta'- lis). The larva of this species sometimes abounds in old stacks of clover-hay, and especially near the bottom of such stacks. As the infested hay be- comes covered with a silken web spun by the larva, and by its black gunpowder-like excre- ment, much more is spoiled than is eaten by the insect. The moth expands about four fifths of an inch. It is of a beautiful lilac color, with golden bands and fringes (Fig. 278). Family GALLERIID^E (Gal-le-ri'i-dae). The Bee-motli Family. This is a small family, of which only seven species have been found in our fauna. The best known of these is the Bee-moth, Galleria mellonella (Gal-le'ri-a mel-lo-nel'la). The VIII FIG. 277.— Wings of Pyr iiialis. 234 THE STUDY OF INSECTS. larva of this species is a well-known pest in apiaries. It feeds upon wax ; and makes silk-lined galleries in the honey- comb, thus destroying it. When full grown the larva is about an inch in length. It lies hidden in its gallery dur- ing the day, and feeds only at night, when the tired-out bees are sleeping the sleep of the just. When ready to pupate the caterpillar spins a tough cocoon against the side of the hive. The moth has purplish-brown front wings, and brown or faded yellow hind wings. The fore wings of the male are deeply notched at the end, while those of the female (Fig. 279) are but slightly so. The female moth creeps into the hive at night to lay her eggs. This pest is found most often in weak FIG. 279.-G,iUeria ,neiio- colonies of bees, which it frequently destroys. The best preventive of its injuries is to keep the colonies of bees strong. Of course the moths and larvae should be destroyed whenever found. But the moths are slippery like other expert thieves, and run so rapidly when disturbed that it is very difficult to catch them. Family CRAMBID.E (Cram'bi-dae). The Close-wings. Although this is not a large family, there being only seventy-five species known in our fauna, the members of it are more often seen than any other Pyralids. The larvae of most of the species feed on grass; and the adults fly up before us whenever we walk through meadows or pastures. When at rest, the moths wrap their wings closely about the body ; this has suggested the name Close-wings for the FIG insects of this family. When one of these moths alights on a stalk of grass it quickly places its body LEPIDOPl^ERA. 235 parallel with the stalk, which renders it less conspicuous (Fig. 280). Many of the species are silvery white or are marked with stripes of that color. More than fifty of our species belong to the genus Cram- bus (Cram'bus). The moths of this genus are often seen; but the larvae usually escape observation. They occur chiefly near the surface of the ground, where they live in tubular nests constructed of bits of earth or vegetable matter. 1113*4 Family PHYCITID^E (Phy-cit'i-dae). The Phycitids (Phyc'i-tids\ Our most common members of this family are small moths with rather narrow but long fore wings, which are banded or mottled with various shades of gray or brown. The family is, however, a large one and other types of col- oration occur. The dis- tinctive characteristics are those given in the table above. Figure 281 represents the venation of the wings. The larvae of the dif- erent species vary greatly V \ "^ VIII FIG. 281.— Wings of Tlascala reductelta. in habits. Some live in flowers, some fold or roll leaves within which they live and feed; some are borers; others feed upon dried fruits, or flour and meal ; and one, at least, is preda- ceous, feeding on coccids. Usually the larva lives in a silken tube or case, lying concealed by day and feeding by night. 236 THE STUDY OF INSECTS. The case made by certain of the leaf-eating species is very characteristic in form (Fig. 282), being strongly taper- ing and much curved ; in this instance the case is composed largely of the excrement of the larva. The Indian-meal Moth, Plodia interpunc- tella (Plo'di-a in-ter-punc-tel'la) is the best known of the species that infest stored provisions. The larva is the small whitish worm, with a brownish - yellow head, that spins thin silken tubes through meal or among yeast-cakes, or in bags or boxes of dried fruits. The moth expands about five eighths of an inch. The basal two fifths of the fore wing is dull white or cream-colored ; the outer part reddish brown, with irregular bands of blackish scales. The Mediterranean Flour -moth, Ephestia kiihniella (E-phes'ti-a kiilin-i-el'la), is an even more serious pest than the preceding species, which it resembles in habits. It has become very troublesome in recent years in flouring-mills. The moth expands about one inch, and is grayish in color. Although it is called the Mediterranean Flour-moth, its source is not definitely known. Nor do we know of any easy way of ridding an infested mill of it. Carbon bisul- phide is perhaps the most available insecticide in this case. Zimmermann's Pine-pest, Pinipestis zimmermanni (Pin-i- pes'tis zim-mer-man'ni), is a common species, the larva of which is a borer. It infests the trunks of pine, causing large masses of gum to exude. The moths appear in mid- summer. The Coccid-eating Pyralid, Latilia coccidivora (Lae-til'i-a coc-ci-div'o-ra), differs from the other members of this family in being predaceous. It feeds on the eggs and young of various scale-insects (Pulvinaria, Dactylopius, and Lecanium}. Figure 283 represents the different stages of this insect enlarged, and the moths natural size resting on LEPIDOPTEKA. 237 egg-sacs of Pulvinaria. Like other members of this family the larva spins a silken tube, within which it lives. On a FIG. ^.-LBtilia coccidirora: a, egg; *, larva ; r, pupa; d, adult; e, t, moths natural size resting on egg-sacs of fulvinana. thickly-infested branch these tubes may be found extending from the remains of one coccid to another. Family Pterophoridae (Pter-o-phor'i-dse). The Plume-moths. The Plume -moths are so called on account of the remarkable form of the wings, which are split by longitu- 238 THE STUDY OF INSECTS. dinal fissures into more or less plume-like divisions. In most species the fore wing is separated into two parts, by a fissure extending about one half the length of the wing; while the hind wing is divided into three parts by fissures extending farther towards the base of the wing. Sixty species belonging to the family have been found in North America. One of our most common species is the Gartered Plume, Oxyptilus periscelidactyhis (Ox-yp'ti-lus per-is-cel-i-dac'ty-lus). This is a small moth, expanding about seven tenths of an inch. It is of a yellowish brown color marked with dull whitish streaks and spots (Fig. 284). The larvae hatch early in the 5PrmS» ancl feeci upon tne newly-expanded *H*c*iiresiaria fieracliana. L EPID OP TERA . 247 ever, in that the second anal vein of the hind wings is not forked towards the base (Fig. 296). The venation of the wings of the more generalized Tineids is quite primitive in type; there are two anal veins in the fore wings, three anal veins in the hind wings, and the base of vein V is preserved throughout the length of the discal cell. But the more specialized members of the superfamily present a wide departure from this gen- eralized type. With these the base of vein V has disappeared from both pairs of wings, and the venation of the hind wings is reduced to a greater extent than is seen elsewhere in winged Lepidoptera. Correlated with this great reduction of the hind wings there has been a great expansion of the fringe of the wing. It is evident that the fringe of the wing takes the place of the wing-membrane as an organ of flight. In those Tineids that we have studied carefully the hairs composing the fringe are inserted in the lower side of the wing- membrane a short distance back from the edge of the wing; and the edge of the wing is stiffened above by strong overlapping scales. This arrangement renders the fringe rigid during the downward stroke of the wing, but admits of its depression during the upward stroke ; a combination well adapted to facilitate flight. The substi- tution of wide fringes for the wing-membrane occurs in some other minute insects, as Thrips and certain minute, parasitic Hymenop- tera. To this superfamily belong the smallest of the Lepidop- tera ; many of them are so minute that the larvae live until full grown within the tissue of leaves. These tiny moths are often very beautiful, their wings being marked with scales that shine like silver or gold ; but they are so small that it is necessary to examine them with a lens to appreciate their beauty. The larvae of nearly all Tineids feed upon vegetable matter. The majority of them feed upon or within the leaves of plants, but many live within nuts, or seeds, or dried fruits; a few feed upon dead animal matter, as woolens, furs, and feathers; and some are predaceous, destroying scale-bugs. Entomologists have a custom of terminating the name of each species of Tineid with -ella. Thus we have Tinea 248 THE STUDY OF INSECTS. granella, Adela ridingsella, Bucculatrix pomonella, and many hundreds of others; until the syllable -ella always brings before us a vision of a tiny moth, with narrow wings bear- ing long delicate fringes. The Tineids are very numerous, there being nearly one thousand described American species ; and doubtless there are many undescribed as yet. The superfamily is composed of several families; but, as the study of these insects is too difficult to be carried far by the beginning student, we will not take the space to define these families in this work. We will merely describe the habits of a few species. At first thought the leaves of our common shrubs and trees seem quite as thin as if they had been cut out of sheets of paper. But the reader has doubtless learned in the study of Botany that the upper and the lower surfaces of a leaf are each covered with a thin skin or epidermis, and that between these two skins there is a fleshy portion called the parenchyma. But if botanists had failed to teach us this lesson, the Tineid larvae would have done so ; for many of these little creatures live until full grown between the two skins of a leaf, and derive their nourishment from the paren- chyma. As our coal-miners dig tunnels in the earth, so do these larvae eat out long passages in the substance of a leaf, without breaking through either epidermis. During the late summer and autumn there can be found on almost any shrub or tree leaves that are more or less dis- colored by white or grayish blotches or by long twisted lines that reveal the abiding-places of leaf-miners. Surely Mr. Lowell must have had these in mind when he wrote : " And there's never a leaf nor a blade too mean To be some happy creature's palace." Not only are very many kinds of plants infested by Tineid larvae, but the mines in the leaves differ greatly in form and in their position in the leaf. These differences in food-plant and in the shape and position of the mines do LEPIDOPTERA. 249 not indicate that these larvae are inconstant in their habits. In fact, the opposite is the case. Each species of Tineid infests a particular species of plant, or, at the most, several closely allied plants. And each species makes a mine of definite shape, although some species exhibit different habits in the different stages of their growth. So constant are these creatures in their habits that in most cases an expert can determine the species of Tineid that made a mine by merely examining the infested leaf. The various kinds of mines can be classed under a few distinct types. The long, narrow, and more or less winding mines are described as linear mines. Some of these are very narrow at their beginning and grad- ually enlarge, resembling in outline a serpent ; fre- quently the larger end is terminated by a blotch- like enlargement, suggest- ing a head. Such mines are termed serpentine mines. The leaves of the wild columbine are often marked by serpentine mines (Fig. 297). Other mines that start from a narrow beginning enlarge more rapidly and extend in a more or less regular curve ; these are trumpet mines. A common example of a trumpet mine is that made by the larva of Tischeria malifoliella (Tis-che'ri-a mal-i-fol-i-el'la) in the leaves of. apple. The mines of many species are mere disk-like blotches ; these are referred to as blotch mines (Fig. 298). Blotch mines differ in position ; some are immediately beneath the upper epider- mis, while others are nearer the lower surface of the leaf. This distinction exists also in most of the other types of FIG. 297.— Leaf with serpentine mines. 250 THE STUDY OF INSECTS. mines. In some of the blotch mines the epidermis of one side of the leaf is thrown into a fold by the growth of the leaf ; these are tentiform mines. In addition to peculiarities in shape many mines are marked by characteristic lines or spots composed of the droppings of the larva. The following species will serve to illustrate the habits of these remarkable insects. The White-blotch Oak-leaf Miner, LitJiocolletis hamadrya- della (Lith-o-col-le'tis ha-mad-ry-a-del'la). — This little miner infests the leaves of many different species of oak, and some- times it is extremely abundant. We have seen trees infested so badly that there were on an average four or five mines in each leaf. Figure 298 represents a leaf from such a tree. The nine is a whitish, blotch mine in the upper side of the leaf. LEPIDOPTERA. 2$ I The young larva is remarkable in resembling more the larva of a beetle than the ordinary type of lepidopterous larvae. It is nearly flat ; the first thoracic segment is much larger than any of the others ; the body tapers towards the hind end ; and there are only the faintest rudiments of legs discernible. The larvae molt seven times. At the seventh molt the form of the body undergoes a striking change. It now becomes cylindrical in form, there is a great change in the shape of the mouth-parts, and the fourteen feet are well developed. This change in form during the life of the larva is charac- teristic of a large group of Tineids of which this species may be taken as a type. The full-grown cylindrical larva meas- ures about one fifth inch in length. It spins a cocoon, which is simply a delicate, semi-transparent, circular sheet of white silk, stretched over a part of the floor of the mine. The pupa is dark brown in color, and bears a toothed crest upon its head, which enables it doubtless to pierce or saw its way out from the cocoon. The moth is a delicate little creature, whose wings expand a little more than one fourth inch. The fore wings are white, with three, broad, irregular, bronze bands across each, and each band is bordered with black on the inner side. The hind wings are silvery. As this insect passes the winter as a larva within the dry leaves, the best way to check its ravages when it becomes a pest is to rake up and burn such leaves. The Palmetto-leaf Miner, Laverna sabalella (La-ver'na sab-a-lel'la). — This species occurs only in the South where the saw-palmetto grows. But it is of general interest as illustrating a peculiar type of larval habit. The larvae can hardly be said to be leaf-miners ; for they feed upon the upper surface of the leaf, destroying the skin as well as the fleshy part of the leaf. They are social, working together in small companies, and make a nest consisting of a delicate sheet of silk covering that part of the leaf upon which they are feeding; this sheet is covered with what appears like sawdust, but which is really a mass of the droppings of the 252 THE STUDY OF INSECTS. larvae (Fig. 299). The full grown larva attains a length of half an inch. The pupa state is passed within the nest made by the larvae. The moth is quite large for a Tineid, the wings expanding five eighths of an inch. Its general color is FIG. 299.— Lt *na sabalella, larva, pupa, adult, and p; the Author's Report for 1879.) rt of injured leaf. (From a delicate silvery gray, with a tinge of lavender in some in- dividuals. The Pine-leaf Miner, Gelechiapinifoliclla(Ge-\erc\\\-3. pin-i- fol-i-el'la). — It often happens that the ends of the leaves of pine present a dead and brown appearance that is due to the interior of the leaf having been eaten out. This is the work of the Pine-leaf Miner (Fig. 300). At the right season it is easy to see the long, slender larva in its snug retreat by holding a leaf up to the light and looking through it ; and later the pupa can be seen in the same way. Near the lower end of the tunnel in each leaf there is a round hole through which the larva entered the leaf and from which the adult emerges. We have found this insect in several of the stouter-leaved species of pine, but never in the slender leaves of the white pine. In the North it is most abundant in the leaves of pitch-pine. LEPIDOPTERA. 253 ^ The Apple Bucculatrix, Bucculatrix pomifoliella (Buc-cu- 'trix pom-i-fol-i-el'la).— This insect differs in habits in sev- la'trix -Gelechia pinifoliella, larva, pupa, adult, and leaves mined by the larvj the Author's Report for 1879.) (From eral respects from any of the other Tineids described here. The larva infests the leaves of apple, and when full grown it makes a small white cocoon which is attached to the lower surface of a twig. These cocoons sometimes occur in great numbers, side by side, on the twigs of an infested tree (Fig. 301). They are easily recognized by their shape being slender, and ribbed lengthwise. It is these cocoons that usually first reveal the presence of this pest in an orchard. They are very conspicuous during the winter when the leaves are off the trees. At this time each cocoon contains a pupa. The adult moth emerges in early spring. The eggs are laid on the lower surface of the leaves. Each larva when it hatches bores directly from the egg to the upper surface of the leaf, where it makes a brown serpentine 254 THE STUDY OF INSECTS. mine. When these mines are abundant in a leaf it turns yellow and dies. When the larva has made a mine from one half to three fourths of an inch long, which it does in from four to five days, it eats its way out through the upper surface. Then somewhere on the upper surface of the leaf it weaves a circular silken covering about one-twelfth inch in diam- eter. Stretched out on this network the larva, which is now about one-tenth inch long, makes a small hole in it near its edge, then, as one would turn a somersault, it puts its head into this hole and disappears beneath the silken covering, where it undergoes a change of skin. It remains in the molting cocoon usually less than twenty-four hours. After leaving this cocoon it feeds upon the leaves without making a mine ; and in a few days makes a second molting cocoon which differs from the first only in being about one- eighth inch in diameter. After leaving this it FIG. 3oi. — Cocoons again feeds for a few days, and then mi- of Bucculatrix pom- . . . . . . grates to a twig where it makes the long ribbed cocoon within which the pupa state is passed. Thi very interesting life-history was first worked out by Mr. A. E. Brunn while a student in the writer's laboratory at Cornell University. When it is necessary to combat this pest the smaller twigs bearing cocoons should be pruned as far as practicable during the winter and burned, and those cocoons that remain on the larger branches should be washed with strong kerosene emulsion. The Resplendent Shield-bearer, Aspidisca splendoriferella (As-pi-dis'ca splen-do-rif-e-rel'la).— This Tineid is both a miner and a case-bearer. It feeds within apple-leaves, and at first makes a linear mine ; but later this is enlarged into a blotch mine. When full grown the larva makes an oval case LEPIDOPTERA, 2$$ cut from the walls of its mine and lined with silk. It then seeks a safe place in which to fasten this case and pass the winter. This is usually on the trunk or on a branch of the in fested tree (Fig. 302). Once some of these migrating larva, dropped from a tree upon the writer's hat and carefully FIG. ^oz.—Aspidisca sflendoriferella : a, leaf of apple showing work; 6, summer larva; c. larva in case travelling ; d, cases tied up for winter ; e, hibernating larva ; ./", pupa; £-, moth ; A, parasite. (From the Author's Report for 1879.) fastened themselves to the band with misplaced confidence that they could remain there till spring. The adult has gray and golden wings with silvery and dark markings. The Maple-leaf Cutter, Incurvaria acerifoliella (In-cur- va'ri-a a-cer-i-fol-i-eria).— This insect illustrates still another THE STUD Y OF INSECTS. curious type of larval habits. It infests the leaves of maple, and occasionally is so abundant that it does serious injury. The leaves of an infested tree present a strange appearance (Fig. 303). They are perforated with numerous elliptical holes, and marked by many more or less perfect ring-like patches in which the green substance of the leaf has been destroyed, but each of which incloses an uninjured spot. These inju- ries are produced as follows: The young larva cuts an oval piece out of a leaf, places it over its back, and fastens it down with silk around the edges. This serves as a house beneath which it lives. As it grows this house becomes too small for it. It then cuts out a larger piece which it fastens to the outer edges of the FIG. 3o3.-Leaf infested by incurvaria. smaller one, the larva being between the two. Then it fastens one edge of this case to the leaf by a silken hinge so that it will not fall to the ground " cradle and all," and then turns the case over so that the larger piece is over its back. When it wishes to change its location it thrusts out its head and fore legs fro*m the case and walks off, looking like a tiny turtle. When it wishes to eat it fastens the case to the leaf and, thrusting its head out, eats the fleshy part of the leaf as far as it can reach. This explains the circular form of the patches, the round spot in the center indicating the position of the case. The insect passes the winter in the pupa state within its case, which falls to the ground with the infested leaf. The moth is of a brilliant steel-blue or bluish-green color without spots ; it appears in early summer. LEPWOPTERA. 2tf Other Case-bearers.— The two case-bearers described above make their cases out of fragments of leaves • there are others that use the husks of seeds which they have eaten. Such cases are extremely protective, appearing to be merely seeds. But there are some Tineid case-bearers that make their cases entirely of silk. These are usually more or less nearly cylindrical, and are carried projecting out at a considerable angle from the object upon which the insect walks. When the insect is at rest and when it is undergoing its transformations the mouth of the case is closely fastened to some object, so that the insect is com- pletely concealed. Considerable differences exist in the form of these silken cases. In a quite common type the case is nearly cylindrical, with a flaring lip at the head end, and with the hind end three-sided, as if it had been pinched between one's thumb and two fingers. In another type the hind end of the case is somewhat enlarged and curved down- ward so that the case is shaped like a pistol. The Clothes-mot/is. — These are the dread of every house- keeper. The mere mention of the word "moths" is enough to conjure up visions of household treasures of woolen and fur eaten full of holes, their beauty gone, their usefulness past. It was formerly supposed that these well-known injuries were caused by a single species ; but it has since been dis- covered that we have in this country three species of clothes- moths. These differ in habits as well as in structure. The Case-bearing Clothes-moth, Tinea pellionella (Tin'e-a pel-li-o-nel'la). — The larva of this species is a true case- bearer, making a case out of bits of its food-material which are fastened together with silk. As the larva grows it en- larges its case by adding to each end and by slitting it and inserting a piece. Instructive specimens can be obtained by rearing the larvae, and changing them from time to time from flannel of one color to that of another. The shape of the successive additions to the case, being of different colors, can be easily seen. The pupa state is passed within the 258 THE STUDY OF INSECTS. case. The adult is a small brown moth with a few dark spots on its fore wings. The Tube-building Clothes-moth, Tinea tapetzella (T. tap-et-zel'la). — The larva of this species makes a gallery composed of silk mixed with fragments of cloth. This gal- lery is long and winding and can be easily distinguished from the case of the preceding species. The pupa state is passed within the gallery. The moth differs greatly in ap- pearance from the other two species, the fore wings being black from the base to the middle and white beyond. The Naked Clothes-moth, Tinea biselliella (T. bi-sel- li-eria). — Although this species spins some silk wherever it goes, it makes neither a case nor a gallery. It may be termed, therefore, the Naked Clothes-moth, in contradistinc- tion to the other two species. But when the larva is full grown it makes a cocoon, which is composed of fragments of its food-material fastened together with silk. The adult is of a delicate straw-color, without dark spots on its wings. Protection from Clothes-moths. — In late spring or early summer all winter clothing, flannels, furs, and other articles that are to be put away for the summer should be thor- oughly brushed or examined for these pests, and exposed to the sunlight as long as practicable. Then they should be wrapped carefully in stout paper, or better packed in paste- board boxes, which can be procured at small cost, and the crack between the cover and the box closed by pasting a strip of paper over it. The Angoumois Grain-moth, Gelechia cercalella (Ge- le'chi-a ce-re-a-lel'la).— Although this insect is closely allied to the Pine-leaf Miner, its habits are very different. This insect feeds upon seeds, and especially upon stored grain. It occurs throughout our country ; but it is especially de- structive in the Southern States. In that part of the coun- try it is extremely difficult to keep grain long on account of this pest and certain beetles that also feed on stored grain. The adult moth is of a very light grayish-brown LEPIDOPTERA. 259 color, more or less spotted with black ; it expands about half an inch. The common name is derived from the fact that it has been very destructive in the province of Angou- mois, France. Family SESIID^ (Se-si'i-dae). The Clear-winged Moths or Sesiids (Se' si-ids). The Clear-winged Moths constitute a very remarkable family, many of them resembling bees or wasps in appear- ance more than they do ordinary moths, a resemblance due to their clear wings and in some cases to their bright colors (Fig. 304). There are a few moths in other families, as the Clear- winged Sphinxes, and certain Zygaenids, that have a greater or less part of the wings devoid of scales ; but they are exceptions. Flc- a°«- Here it is the rule that the greater part of one or both pairs of wings are free from scales; hence the common name Clear-winged Moths. These insects are of moderate size ; as a rule they have spindle-shaped antennae, which are terminated by a small silky tuft ; sometimes the antennae are pectinate ; the margins of the wings and the veins of even the c 1 ea r- winged species are clothed with scales ; and at the end of the abdo- men there is FIG. 305.— Wings of Sanninn e.vi'tiota, female. a fan-like tuft of scales. The fore wings are remarkable for their extreme narrow- 260 THE STUDY OF INSECTS. ness and the great reduction of the anal area (Fig. 305) ; while the hind wings have a widely expanded anal area. There is great variation within the family in the number of anal veins in the hind wings, the number ranging from two to four. The maximum number of anal veins in the Lepi- doptera has generally been considered to be three ; but in certain forms belonging to this family a fourth (vein X) is quite well represented. Another remarkable feature of all tne forms that we have studied is that in the female the bristles composing the frenulum are consolidated as in the male. The females also possess a frenulum hook ; but this is not so highly specialized as that of the male. The adults fly very swiftly and during the hotter part of the day. They frequent flowers, thus increasing their resem- blance to bees or wasps. The larvae are borers, living within the more solid parts of plants. Some species cause serious injury to vegetation. Nearly one hundred and fifty species have been found in this country. Doubtless many more exist ; for the family has not been thoroughly studied as yet. The following species have attracted much attention on account of their serious ravages. The Peach-tree Borer, Sannina exitiosa (San-ni'na ex-it-i- o'sa). — This is the most important insect enemy of the peach-tree. In some parts of the country it is difficult to find a peach-tree that is not infested by it. The eggs are laid on the bark of the tree near the ground. The larvae bore downward in the bark of the trunk just below the sur- face of the ground. Their burrows become filled by a gummy secretion of the tree. As this oozes out in large masses the presence of the borer is easily detected by it. When full grown the larva comes to the surface of the ground and makes a cocoon of borings fastened together with silk. The perfect insects appear from May till October, but most of them in the latter part of June and early in July. There is a single generation each year. The adults 1 -' LEPIDOPTERA. 26 1 differ greatly in appearance. The general color of both sexes is a glassy steel-blue. In the female (Fig. 306) the fore wings are covered With scales, and there is a bright orange-colored band on the abdomen. In the male both pairs of wings are nearly free from scales. No better method of fighting this pest has been found than to care- FlG" 3o6.-J««««« «///««. fully watch the trees and remove the larvae with a knife as soon as discovered. The Pacific Peach-tree Borer, Sannina pacifica (S. pa- cif'i-ca). — On the Pacific Coast there is a peach-tree borer that is distinct from the above, and appears to be an even more serious pest. The larva is more difficult to remove from the tree, as it bores into the solid wood. The female of this species lacks the orange-colored band on the abdomen. The Currant Borer, Sesia tipuliformis (Se'si-a tip-u-li-for'- mis). — This species is closely allied to the two preceding, but is smaller, expanding only about three fourths of an inch. There are but few scales on either pair of wings except on the tip and discal vein of the fore wings and the outer margin of the hind wings. The eggs are laid on the twigs of currant. The larvae penetrate the stem, and de- vour the pith ; in this way they make a burrow in which they live and undergo their transformations. The perfect insects appear in June. Before this time the leaves of the infested plant turn yellow. If such plants be cut and burned in May the pest will be destroyed. The Pine Sesian, Harmonia pint (Har-mo'ni-a pi'ni).— Frequently there may be seen on the trunks of pine-trees large masses of resinous gum mingled with sawdust-like matter. These are the results of the work of the larva: of this insect, which bore under the bark and into the superficial layers of the wood. The adult resembles the female of the Peach-tree Borer, but the abdomen is more extensively marked with orange. 262 THE STUDY OF INSECTS. The Squash-vine Borer, Melittia ceto (Me-lit'ti-a ce'to). — The larva of this species (Fig. 307) does great damage by eating the interior of squash-vines. In some places it is FIG. 307.— Melittia ceto, larva in squash-vine. almost impossible to raise squashes on account of its rav- ages. The fore wings of the adult are covered with scales, and the hind legs are fringed with long orange-colored scales. Family DIOPTID.E (Di-op'ti-dae). The Dioptids (Di-op' tids). This family is represented in our fauna by a single known species, Phryganidia californica (Phryg-a-nid'i-a cal-i-for'- FIG. y&.—Pkryeanidia californica. ni-ca), which occurs in Califor- nia. This is a pale-brown insect, with nearly transparent wings (Fig. 308). The veins of the wings are dark, which renders them prominent. In the males there is a yellowish spot just beyond the discal cell FIG. 309.— Wings of Phryganidia. The venation of the wings LEPIDOPTERA. 26$ (Fig. 309) is very different from that of any other insect that occurs in this country. The larvae feed upon the leaves of live-oaks, and some- times occur so abundantly as to almost strip the trees of their foliage. They are said to feed singly, and appear to make little if any use of the anal feet as a means of loco- motion, generally carrying the last segment of the body elevated in the air. Family NOTODONTlDyE (No-to-don'ti-dae). The Prominents. This family includes moths of moderate size, only a few of the larger ones expanding more than two inches. With these moths the body is rather stout and densely clothed with hair, and the legs, especially the femora, are clothed with long hairs. The wings are strong, and not very broad, the anal angle of the hind wings rarely reaching the end of the abdomen. In their general appearance many of these moths bear a strong resemblance to the Owlet Moths or Noctuidae ; but they can be easily distinguished from the Noctuids by the position of vein V2 of the fore wings, which does not arise nearer to vein VII than to vein III, as it does in that family. In some species the front wing has a prominence or backward - project- ing lobe on the in- ner margin, which has suggested the common name of Prominents for these insects (Fig. 310). The name is more generally ap- propriate, however, for the larvae, as a much larger propor- tion of them than of the adults bear striking prominences. 264 THE STUDY OF INSECTS. The characteristic features in the structure of the wings are the following (Fig. 311): the fore wings have a single anal vein, the hind wings two ; in both wings cubitus is apparently three- branched ; and the subcosta of the hind wings does not make a sharp bend into the humeral angle as it does in the Geometridae (Fig. 323). In some forms the basal part of vein V is more or less distinctly pre- served ; and in some an accessory cell is present. FIG. 311.— Wings of Notodonta stragula. The larvae feed upon the leaves of shrubs and trees. Our most common species live exposed ; but some species live in folded leaves. They are either naked or thinly clothed with hairs. Many species have only four well-developed pro- legs, the anal pair being rudimentary, or transformed into elongated spikes. Some species are hump-backed; and spines or fleshy tubercles are often present. The trans- formations occur in slight cocoons or in the ground. The family is a large one, more than one hundred species occurring in the United States. The following are some of the more common species : — The Handmaid Moths, Datana (Da-ta'na).— Among the more common representatives of the Notodontidae are cer- tain brown moths that have the fore wings crossed with bars of a different shade (Fig. 312), and that bear on the LEPIDOPTERA. 265 fore part of the thorax a conspicuous patch of darker color, in most of our species the fore wings are also marked with a dot near the center of the discal, cell and a bar on the discal vein.1 These moths belong to the genus Datana. The common name, Handmaid, is a translation of the specific name of our most com- mon species, D. ministra (D. mi-nis'tra). But as this species is now generally known as the Yellow-necked Apple-tree Worm, and as all of our species are dressed in sober at- tire as becomes modest servants, we have applied the term Handmaid Moths to the entire genus. The larvae of the Handmaid Moths are easily recognized by their peculiar habits. They are common on various fruit and forest trees, but especially on apple, oak, and hickory. They feed in colonies ; and have the habit of assuming the FIG. 312.— Data FIG. 313. — Datatta, larva. curious attitude shown in Figure 313. The body is black or reddish, marked with lines or stripes of yellow or white. Owing to the gregarious habits of these larvae they can be easily collected from the trees they infest. All of the species that we have studied 'agree in being single-brooded, the moths appearing in midsummer; the 266 THE STUDY OF INSECTS. eggs are laid in a cluster on a leaf; the larvae are con- spicuous in August and September. In some of the species the larvae have the curious habit of leaving the branch upon which they are feeding when the time to molt arrives, the whole colony gathering in a large mass on the trunk of the tree, where the molt takes place. The pupa state is passed in the ground, in a very light cocoon or in none at all, and lasts about nine months in the species that we have bred. The White-tipped Moth, Edema albifrons (E-de'ma al'bi-frons). — This beautiful moth, which is quite common, can be easily recognized by the accompanying figure (Fig. •g^^v / ^^ 314); the white patch, which ^^fS^^^^^^^^Sfs extends along the costa of the RF f°re wing for half the length •*.- |& from the tip, being very char- **•*-->*" 5 I^KHr acteristic. The larva (Fig. 315} %? is quite common in the autumn FIG. y+.-Edema albifrons. on leaves of Oak. It IS SniOOth and shining, with no hairs; along each side of the back there is a yellow stripe, and between these, on the back, fine black lines on a pale lilac ground ; on each side below the yellow stripe there are three black lines, the lowest one just above the spiracles. The head is orange-red ; and there is an orange-red hump on the eighth abdominal segment. FIG. 315.— Edema albifrons, larva. The Two-lined Prominent, Seirodonta bilineata (Seir-o- don'ta bi-lin-e-a'ta).— The larva of this species (Fig. 316) is much more apt 'to be observed than the adult. It is com- mon in the latter part of the summer and in early autumn, LEPIDOPTERA. 267 feeding on the leaves of oak, elm, and basswood. It measures when full grown about one and one half inches in length. Its FIG. yiG.-seirodonta biiineata, ground-color is usually green, but larva- sometimes claret-red. There is a pale yellow stripe along the middle of the back, and on each side a stripe of the same color. The course of these side stripes is very characteristic ; passing back from the head, they converge on the prothorax ; on the mesothorax and metathorax they are separated from the dorsal line only by a narrow band of red or purple; on the first abdominal seg- ment they diverge to the lateral margin of the back, but converge again on the seventh and eighth abdominal seg- ments. This yellow subdorsal line is bordered without by a milk-white stripe ; and extending from this stripe over the side of the body there is a whitish shade which fades out below. The moth is ash-colored, with the fore wings crossed by two wavy lines between which the wing is darker ; be- tween the outer wavy line and the outer margin of the wing there is a faint band. The Red-humped Apple -worm, (Edemasia concinna (CEd-e-ma'si-a con-cin'na).— The larva of this species (Fig. 3 1 7) is common on apple and allied plants. The head is coral- FIG. 317.— (Edemasia concinna, larva. red, and there is a hump of the same color on the back of the first abdominal segment ; the body is striped with slender black, yellow, and white lines, and has two rows of black 268 THE STUDY OF INSECTS. spines along the back, and other shorter ones upon the sides. When not eating, the larvae remain close together, some- times completely covering the branch upon which they rest. This species passes the winter in the pupa state. The adults appear in June and July. The Mocha-stone Moths, Ichthyura (Ich-thy-u'ra). — To the genus Ichthyura belong several species of brownish-gray moths, whose fore wings are crossed by irregular whitish lines. It was these peculiar markings, resembling somewhat those of a moss-agate, that suggested the popular name given above. The larvae feed on poplar and willow, and conceal themselves within nests made by fastening leaves together. Our most common species is the following : — The Poplar Mocha-stone Moth, IchtJiyura inclusa (I. in- clu'sa). — The adult (Fig. 318) is a brownish-gray moth, with the fore wings crossed by three irregu- lar whitish lines. The basal line is broken near the middle of the wing ; afid the intermediate one forms an in- verted Y, the main stem of which joins FIG. y*.-ichthyura inciusa. the third line near the inner margin of the wing, making with it a prominent V. These lines are bordered without by rust-red ; there is a chocolate-colored spot near the apex of the fore wings, and an irregular row of blackish dots near the outer margin. The hairs of the thorax form a prominent crest, the fore side of which is a rich dark brown. The hind wings are crossed by a wavy band, which is light without and dark within. The eggs are nearly spherical and smooth; they are deposited in a cluster a single layer deep on a leaf (Fig. 319)- When the larvae hatch they make a nest either by fastening several leaves together or, as is the case when they infest poplar, by folding the two halves of a single leaf together; frequently in the latter case the tip of the leaf is folded in as shown in the figure. Within this nest the entire colony lives, feeding on the parenchyma, and causing the LEPIDOPTEtA. 269 leaf to turn brown. Later other leaves are added to this nest or additional nests are made among adjoining leaves. All of these infested leaves are securely fastened to the twig by bands of silk. When the larvae become large they leave their nests at night to feed upon other leaves. These they entirely consume excepting the petioles, midribs, and larger FIG. 319.— Eggs, larva, and nest of Ichthyura inclusa. veins. We have seen on poplar a nest composed of only three leaves which contained one hundred and twenty-five half-grown larvae ; all of the leaves, about thirty in number, arising from the end of the branch bearing this nest had been consumed. The full-grown larva measures one and one half inches in length. It is striped with pale yellow and brownish black, and bears a pair of black tubercles close together on the first abdominal segment, and a similar pair on the eighth abdominal segment. The cocoon is an irregular thin web ; it is made under leaves or other rubbish on the ground. The insect remains in the pupa state during the winter, and emerges as a moth in the latter part of June or later. In the South this species infests willow as well as poplar, and is double-brooded. Among the most grotesque of larvc-e be- longing to this family are those of the genus Calodasys \ 2;o THE STUDY OF INSECTS. (Cce-lod'a-sys), of which we have several species. One of these is represented by Figure 320. At the left in the figure is shown a front view of the longest tubercle. Superfamily GEOMETRINA (Ge-o-me-tri'na). The Geometrids (Ge-om1 e-trids), or the Measuring-worms, The peculiar way in which the larvae of Geometrids walk attracts general attention, and has won for them the name of Measuring-worms *^Pi!&2^ (Fig- 321)- As children we had |H \^^P^ *he dislike for "worms" that is ,8^,^>* common to people that are un- educated to the beauties of na- ^^^^^^W ture. All larvae were " worms "; and we never thought of admir- FIG. 321. — A Measuring-worm. . ., . , .. f , , c ing their beautiful colors, or of watching them build interesting houses, or of keeping them till they spun their silken cocoons. But the measuring- worms were excepted from this dislike. We always found these delicate, greenish or yellowish caterpillars with their looping motion vastly interesting. We allowed them to measure our fingers with their little tickling feet, and we counted each length as a yard. We were always delighted with the way they had of standing on their hind legs, rear- ing the body up into the air, and moving the head around, as if looking at the scenery. And then, if one became frightened in any way, it would drop suddenly, suspended by a silken cord, which it seemed to have mysteriously con- cealed in its mouth ; and down it would go, doubling and whirling around and around frantically until it reached the ground. Sometimes we found these fellows on branches of trees, clinging by their hind legs, standing out straight, stiff, and motionless, and appearing like twigs of the tree. We had not heard then of protective resemblances, and did not know that the assuming of this strange attitude protected LEPIDOPTERA. 271 these worms from the sharp-eyed birds. If so, we should have been still more interested in them ; and we should have been even more so could some one have told us of the transformation of these loopers first into pupae and then into beautiful moths. But in those days comparatively few people thought it worth while to study insects. The larvae of Geometrids have as a rule only the last two pairs of prolegs well developed ; and hence, as the middle part of the body is not supported, they are unable to walk in the way that other caterpillars walk. It is probable, however, that the loss of the first three pairs of prolegs is the result of the looping gait rather than the cause of it. That is to say, the ancient Geometrid lar- vae acquired the habit of looping, after which the prolegs under the middle of the body, being unnecessary and not used, dwindled away in succeeding generations. In the case of a few members of this family three or even four pairs of pro- legs have been re- tained. The Geometrid lar- vae are mostly leaf-eat- ing, and some species, as the Canker-worms, occur in such large numbers as to be serious pests. The pupae are slender, and some species are green or mottled in color in this state. The pupa state is passed in a very flimsy cocoon or in a cell in the ground. FlG. 323._wings of C 2/2 THE STUDY OF INSECTS. The moths are of medium size, sometimes small, but only rarely very large. Usually the body is slender, and the wings broad and delicate in appearance. This appearance is due to the fineness of the scales with which the wings are clothed. These moths occur on the borders of woods and in forests, rarely in meadows and pastures. Their flight is neither strong nor long sustained. When at rest the wings are spread horizontally and scarcely overlap each other. The distinguishing features in the venation of the wings of the Geometrina are that vein Vs of the fore wings is not more closely joined to cubitus than to radius, cubitus being apparently three-branched, and that the basal part of vein II of the hind wings makes a prominent bend into the hu- meral angle of the wing (Figs. 322, 323).* Except in the more specialized forms where it has disappeared there is a rudiment of vein I of the hind wings. This usually extends from near the base of the frenulum to the angle in vein II (Figs. 322, 324). In Eudule (Fig. 323) and allied forms the rudiment of vein I lies some distance from the margin of the wing. There occur in our fauna representatives of five families; these can be separated by the following table : — A. Vein V» of the hind wings wanting, being represented merely by a fold in the wing (Fig. 327). p. 277. ENNOMIDJE. AA. Vein Va of the hind wings present. B. Vein Va of the hind wings arising much nearer to vein Vi than to vein V, (Fig. 343). Wings usually green, p. 287. GEOMETRID^E. BB. Vein Va of the hind wings arising nearly midway between veins V, and V, or nearer to vein Va than to vein Vi. Wings rarely green. * In the more specialized forms the humeral angle is greatly expanded (Fig. 343), and in some the frenulum is completely supplanted by it (Fig. 335). The loss of the frenulum in this family, however, occurs only in highly spe- cialized forms ; while in that series of families that we have called the Fren- ulum-losers it has occurred in all except a very few extremely generalized forms. LEPID OP TERA . 2?$ C. Veins II and III of hind wings extending distinctly separate from each other, except that they are connected by a cross vein near the middle of the discal cell (Fig. 335). p. 282. HYDRIOMENID^E. CC. Veins II and III of hind wings approximated or coalesced for a greater or less distance. D. Veins II and III of the hind wings closely approximated but not coalesced along the second fourth (more or less) of the discal cell. E. Veins III and Vi of hind v/ings separating at or before the apex of the discal cell (Fig. 327). p. 277. ENNOMID^G. EE. Veins III and Vi of hind wings coalesced for a consider- able distance beyond the apex of the discal cell (Fig. 324). p. 273. MONOCTENIID.E. DD. Veins II and III of hind wings coalesced for a greater or less distance. E. Veins II and III of the hind wings coalesced for a short distance near the beginning of the second fourth of the discal cell, thence rapidly diverging (Fig. 341), p. 286. STERRHID^;. EE. Veins II and III of the hind wings coalesced to or be- yond the middle of the discal cell (Fig. 334). F. Fore wings with one or two accessory cells, p. 282. HYDRIOMENID/E. FF. Fore wings without an accessory cell (Alsophzla). , MONOCTENIID^E. Family MONOCTENIID.E (Mo-noc-te-ni'i-dae). The Monoctemids (Mon-oc-te' ni-ids). This family includes only a small number of North American species ; but among them are those that are the most important to us from an economic standpoint of all the Geometrids. The family is also of especial interest from a scientific point of view; for to it belong the most primitive forms of the Geometrina, certain genera, found in Australia, being closely allied to the Notodontidae, according to the observa- tions of Mr. Meyrick. 2/4 THE STUDY OF INSECTS. In the typical forms, vein Va of the hind wings is present, and veins II and III of the hind wings are closely approxi- mate, but do not co- alesce along the second fourth of the discal cell (Fig. 324). In many gen- era veins III and V, of the hind wings coalesce beyond the apex of the discal cell (Fig. 324). This character is of use in distinguishing certain members of this family from those of the En- nomidae that retain vein Va of the hind wings. In that family a similar coalescence of veins III and V, does not take place till after the loss of vein Va. In one of our genera veins II and III of the hind wings coalesce along the second fourth of the discal cell, as they do in the Hydriomenidae ; but the absence of an accessory cell in the fore wings at once distinguishes this genus from the Hydri- omenids. The following species are our best known repre- sentatives of the family. The Firstborn Geometer, Brephos infans (Bre'phos in'- fans). — This interesting species has been found only in the northeastern part of our country ; its range is from Labrador to New York. It is a blackish-brown moth with the fore wings marked with pinkish white and the hind wings with reddish orange ^ ™-Bre*hos **""• male- (F'g- 325). The specimen figured is a male. In the female FIG. 324.-Winfi:s of Brefhos infans. LEPIDOPTERA. 2?$ the black border on the outer margin of the hind wings is narrower, and the subterminal light band on the fore wings is more distinctly marked. The early stages of this species are unknown ; but the larvae of European species feed upon birch and poplar. With these the prolegs are all present ; but the first three pairs are stunted. As this is probably the most primitive Geometer occurring in our fauna, we suggest the popular name Firstborn for it. In Germany an allied species is known as the Jungfernkind. Canker-worms. — In many parts of our country Canker- worms are extremely abundant. In such localities they are among the more important of insect pests, often completely stripping the foliage from fruit and shade trees. There are two distinct species of Canker-worms; but they resemble each other so closely that they were long confounded ; and to this day they are distinguished only by entomologists. The two species agree in being loopers or measuring-worms in the larval state, in the possession of ample wings by the adult male, and in the adult female being wingless. They differ in structural characters, as indicated below, and also to a certain extent in habits. In one species the greater num- ber of moths mature in the autumn and emerge from the ground at this season ; in the other species the insects re- main in the pupa state during the winter, emerging as moths in the spring. The two species are therefore appropriately designated as the Fall Canker-worm and the Spring Canker- worm respectively. The Spring Canker-worm, Paleacrita vernata (Pal-e-ac'ri-ta ver-na'ta). — The eggs are ovoid in shape, and are secreted in irregular masses, usually under loose scales of bark or be- tween the leaflets of the expanding buds. The larvae hatch about the time the leaves expand, and become full grown in from three to four weeks. They vary greatly in color, and are marked on the back with eight narrow, pale, longitudinal lines which are barely discernible ; the two lateral lines of each side are much farther apart than the others ; and there are 276 THE STUDY OF INSECTS. no prolegs on the fifth abdominal segment. The pupa state is passed below the surface of the ground in a simple earthen cell, which is lined with very few silken threads. The adult moths usually emerge early in the spring before the leaves expand ; but they sometimes appear late in the fall, or on warm days during the winter when the ground is thawed. In both sexes the adult of this species is distinguished by the presence of two transverse rows of stiff reddish spines, pointing backwards, on each of the first seven abdominal seg- ments. In the male the venation of the wings very closely resembles that of Brephos (Fig. 324); veins II and III of the hind wings although closely approximate do not coalesce, and veins III and V, coalesce for a considerable distance be- yond the apex of the discal cell. The Fall Canker-worm, Alsophila pometaria (Al-soph'i-la pom-e-ta'ri-a). — The eggs appear as if cut off at the top, and have a central puncture and a brown circle near the border of the disk. They are laid side by side in regular rows and compact batches, and are generally exposed. They hatch in the spring at the time the leaves appear ; and the larvae mature in about three weeks. The larva is of a pale brown- ish color marked with dark brown and yellow ; the body is marked on the back with six broad and very distinct pale lines, those of each side equidistant ; and there is a pair of distinct prolegs on the fifth abdominal segment. As in the preceding species the pupa state is passed beneath the ground, but this species makes a perfect cocoon of fine densely spun silk. The adult moth usually emerges in the fall, generally beginning about the middle or latter part of October ; although a con- siderable number come out of the earth in the winter during warm F.G. 3a6.-x/,J^r~ weather and in the spring. The moths of both sexes lack the ab- dominal spines characteristic of the Spring Canker-worm. LEPIDOPTERA. 277 The male is represented by Figure 326. In this species veins II and III of the hind wings coalesce for a considerable distance along the second fourth of the discal cell ; and veins III and V, of the hind wings separate at the apex of the dis- cal cell. The two species of Canker-worms are sufficiently alike in habits to warrant our combating them by similar methods. The fact that in each the female is wingless and is thus forced to climb up the trunks of trees in order to place her eggs in a suitable place has suggested the method of defence that has been most generally used in the past. This is to place something about the trunks of the trees which will make it impossible for the wingless female to ascend them. Some viscid substance, as tar, printers' ink, or melted rubber, either painted on the trunk of the tree or upon a paper band which is tacked closely about the tree, is the means usually adopted. Many other devices have been recommended. In the use of this method of prevention, operations should be begun in the autumn, even when it is the Spring Canker- worm that is to be combated. For in this species some of the moths emerge in the fall or during the winter. Although the method just described is still the most avail- able one when tall shade-trees are to be protected, it is now rarely used in orchards. Here the spraying of the trees with Paris-green water soon after the leaves appear is found more practicable. This method has also the advantage of enabling the fruit-grower to reach other important pests, as the Codlin-moth, at the same time. Family ENNOMlD-fi (En-nom'i-dae). The Ennomids (En' no-mids). Nearly all of the members of this family can be easily recognized as such by the fact that vein V, of the hind wings is wanting, being represented merely by a fold. In a few species this vein has been preserved; these can be recog- 278 THE STUDY OF INSECTS. nized by the following combination of characters : Vein V, of the hind wings does not arise much nearer to vein V\ than to vein V3 (as it does in the Geomet- ridae), veins II and III of the hind wings are closely approximate but do not coalesce along the second fourth, more or less, of the discal cell (Fig. 327), and veins III and V\ of the hind wings do not coalesce beyond the apex of the discal cell. This last char- acter does not apply- to the family as a whole, but merely to those that retain vein V, of the hind wings; jn some of thOSe ill FIG. 327.-Wings of Caripeta angusti which this vein is lost, the coalescence of veins III and V, is carried beyond the apex of the cell. This is by far the largest of the families of the Geome- trina and contains the greater number of our larger species. The following will serve as illustrations of it : — The Notched-wing Ge- ometer, Ennomos magnarius (En'no-mos mag-na'ri-us), is one of the largest of our Geometrids. The larva is a common looper upon maple, chestnut, and birch trees, and measures about two and one third inches in length LEPIDOPTERA. 279 FIG. yg.—Diaitictis ribearia. when full grown. It spins a rather dense, spindle-shaped cocoon within a cluster of leaves. The moth (Fig. 328) is ochre-yellow with a reddish tinge. The wings are shaded towards the outer margin with brown, and are thickly spotted with small brown dots. The Currant Span-worm, Diastictis ribearia (Di-as-tic'tis rib-e-a'ri-a).— There are several species of insects that are popularly known as currant- worms. The most common of these are larvae of saw- flies, which can be easily recognized by the large number of prolegs with which the abdomen is fur- nished. In addition to the saw-flies there is a yellow looper spotted with black, which often appears in such great numbers on currant and gooseberry bushes as to suddenly strip them of their foliage. This larva has been named the Currant or Gooseberry Span-worm. When full grown it measures about one inch in length, and is of a bright yellow color, with white lines on the sides and with numerous black spots and round dots. It has only four prolegs. There is only a single brood ; the larva matures in May or June ; the pupa state lasts about a fortnight ; the moth flies during the summer months and oviposits on the twigs of the plants ; and the eggs remain un- hatched till the following spring. The moth (Fig. 329) is pale yellow, with the wings marked by ir- regular dusky spots, which sometimes form one or two indefinite bands across them. The Chaill-dotted GeOni- eter, Cingilia catcnaria (Cin-gil'i-a cat-e-na'ri-a). — This moth 28o THE STUDY OF INSECTS. has snow-white wings marked with zigzag lines and with dots of black as shown in Fig. 330. The head is ochreous- yellow in front ; and the thorax is yellowish at the base of the patagia. The moth flies during September and October. The larva feeds on various shrubs and trees. The pupa state is passed in a slight but well-formed web of yellow threads, which is formed between twigs or leaves, and through which the pupa can be seen. The Evergreen Cleora, Cleora semiclusaria (Cle'o-ra sem-i-clu-sa'ri-a).— This beautiful moth (Fig. 331) is common in the vicinity of pines, spruce, fir, and hemlock during August and September. It varies from a smoky-ash color to almost snow - white ; the wings are marked with black. The larva feeds on the leaves of Conifers. It is reddish yellow above, with on each side are two pairs of black hair-lines. There are black spots above on the segments. When full grown it is a little more than an inch long and spins a loose cocoon among the leaves. The chrysalid is green with white stripes and is very pretty. The Pepper-and-salt Currant-moth, Biston cognataria (Bis'ton cog-na-ta'ri-a). — This moth (Fig. 332) differs remark- ably in appearance from most Geometrids, the body being stouter, and the wings appearing heavier. It can be easily recog- nized by its evenly distributed pepper-and-salt markings. The FIG. 33*.-*"" larva feeds on various plants, but is found most often on currant. The Lime-tree Winter-moth, Erannis tiliaria (E-ran'nis LEPIDOPTERA. 28 1 til-i-a'ri-a).— This species (Fig. 333) resembles the Canker- worms in many particulars. The larva is a looper which infests both fruit and forest trees; and in the adult state the male has well-developed wings, while the female is wingless. The eggs are oval, of a pale yellow color, and covered with a network of raised lines. They are thrust by the FIG. 333. — Erannis tiliaria. (From the Author's Report for 1879.) female under loose bark and in crevices on the trunk and large limbs. They hatch in May, and the larvae attain their full growth in the latter part of June. The larva is yellow, marked with ten crinkled black lines along the top of the back; the head is rust-colored, and the venter yellowish white ; when full grown it measures about one and one fifth inches in length. The pupa state is passed in the ground, from three to six inches below the surface. The moths issue in October, and then the wingless females ascend the 282 THE STUDY OF INSECTS. trees to oviposit as do the females of the Canker-worms. The female is represented in the lower left-hand part of the figure. She is grayish in color, with two black spots on the back of each segment except the last, which has only one. The male has buff fore wings, with a central spot and a band beyond the middle, while the hind wings are much lighter. This insect can be combated by the same methods as are used against canker-worms. Family HYDRIOMENIDS (Hyd-ri-o-men'i-dae). The Hydriomenids (Hyd-ri-o-me'nids). The Hydriomenids are easily recognized by the structure of their wings. In the fore wings the branches of radius anastomose so as to form one or two accessory cells; and in the hind wings veins II and III coalesce along the second fourth of the discal cell, the co- alescence extending to or beyond the middle of the F.6- 334- Wings of Eudul, mendica. F,G. 335-Wings of Dyifteri* abo, tivaHa. LEPIDQPTERA. 283 discal cell (Fig. 334). The only exception to these char- acters known to us is shown by certain genera (e.g., Heteroph- leps and Dyspteris) in which, owing to a large expansion of the costal area of the hind wings, veins II and III have been pulled apart as it were, and are connected only by a cross-vein near the middle of the discal cell (Fig. 335). In a single genus (Paleacrita) not belonging to this* family veins II and III of the hind wings coalesce to the middle of the discal cell ; but this genus lacks the accessory cell in the fore wings characteristic of this family. This family ranks second in size among the Geometrid families, and contains many common species. The White-striped Black, Eucha?ca albovittata (Eu-chce'ca al-bo-vit-ta'ta). — This beautiful little moth, which occurs from the Atlantic to the Pacific, is the most easily recog- nized member of the family. It expands about seven eighths of an inch, and is of a uniform black color, with a single, very broad white band extending across the fore wing from the middle of the costa to the inner angle, where it is usually forked. The fringe of the wings is white at the apical and inner angles of both pairs ; sometimes the white is lacking on the inner angle of the hind wings. The early stages of this beautiful moth are unknown. The Spear-marked Black, Plemyria hastata (Ple-myr'i-a has-ta'ta). — This is another black-and-white species, occur- ring from the Atlantic to the Pacific. It is much larger than the preceding, expanding one and four tenths inches. It is black, striped and spotted with white. It varies greatly as to the number and extent of the white markings. The most constant mark is a broad white band crossing the middle of the fore wings, and often continued across the hind wings. Near the middle of its course on the fore wing this band makes a sharp angle pointing outward ; and just beyond the apex of this angle there is usually a white spot. This spot and angular band together form a mark shaped something like the head of a spear. In some speci- 284 THE STUDY OF INSECTS. mens the white predominates ; other specimens are almost entirely black, excepting the spear-mark. According to Eu- ropean authorities the larva is brown or blackish brown, with a darker line along the middle of the back, and a row of horse- shoe-shaped spots on the sides. It feeds on birch and sweet gale. It is gregarious, a colony of larvae spinning together the leaves of the food-plant, and thus forming a nest within which they live and feed. The larva has not yet been observed in this country. The Scallop-shell Moth, Calocalpe nndulata (Cal-o-cal'pe un-du-la'ta). — This is a pretty FIG. 336.— Calocalpe nndulata. moth, with its yellow wings crossed by so many fine, zigzag, dark brown lines that it is hard to tell which of the two is the ground-color (Fig. 336). It lays its eggs in a cluster on a leaf near the tip of a twig of cherry, usually wild cherry. The larvae make a snug nest by fastening together the leaves at the end of the twig; and within this nest (Fig. 337) they live, adding new leaves to the ^ • , , FIG. 337. — Eggs and nest of Calocalpe outside as more food is needed. unduiata. The leaves die and become brown, and thus render the nest conspicuous. The larvae are black above, with four white LEPIDOPTERA. 285 stripes, and flesh-colored below. When full grown they descend to the ground to transform, and pass the winter in the pupa state. The Diverse-line Moth, Eustroma diversilineata(£\\s-\.vQ'. ma di-ver-si-lin-e-a'ta)'.— This moth has pale ochre-yellow wings, with a brownish shade near the outer margin, and crossed by many diverging brown lines (Fig. 338). It varies from one inch and a half to two inches in expanse. We have often found this moth on the side of our room, resting on the wall, head downward, and with its abdomen hanging down over its head in a curious manner. The larva feeds on the leaves of grape. There are two broods ; the first brood infests the vines during June ; the second, in the autumn and early spring, wintering as larvae. FIG. 338. — Eustronta diversilineata. FIG. 339. — Eudule mcndica. The Beggar, Eudule mendica (Eu-du'le men-di'ca). — One of the most delicate winged moths that we have in the Northern Atlantic States is this species (Fig. 339). Although- the wings are yellowish white in color they are almost trans- parent. On the fore wings there are two transverse rows of pale gray spots, and a single spot near the outer margin be- tween veins V3 and VII,. (This spot was indistinct in the specimen figured.) The moth is common in midsummer. We do not know what fancy led the naturalist that de- scribed this species to name it mendica. But it seems ap- propriate now to call it a mendicant ; for during the thirty years that have elapsed since the species was described it has not been allowed a position in its own family, but has been catalogued in the Lithosiidae, although it was shown to be a Geometrid long ago. 286 THE STUDY OF INSECTS. The Bad-wing, Dyspteris abortivaria (Dys'pte-ris a-bor- ti-va'ri-a).— It is easy to recognize this moth (Fig. 340) by the peculiar shape of its wings, the hind wings being greatly reduced in size. It is of a beautiful pea-green color, with two white bands on the fore wings and one on the hind wings. Its color has led to its being placed heretofore in the Geometridae ; FlG. 340.— Dyspteris abortivaria. \>^ {fog structure of its willgS sllOWS it to be an Hydriomenid. The larva feeds on the leaves of grape, which it rolls. Family STERRHID^: (Ster'rhi-dae). The Sterrhids (Ster'rhids). The members of this family are most easily recognized by the venation of the hind wings (Fig. 341). In these veins II and III co- alesce for a short distance near the beginning of the second fourth of the dis- cal cell and then diverge rapidly. The greater number of our common species are of medium size, with whitish wings crossed by from two to four indistinct lines, and with the head black in front ; some are pure white, and others are brown marked with red- dish lines. About one hundred species have been found in this country. FlG. 34I._Wings of Synelys LEPIDOPTERA. 287 ' g * t**t*/ *-tt \llcC- w FlG. 342.— Hirmatopis grataria. The Chickweed Geometer, Hcematopis grataria (Hae- mat'o-pis gra-ta'ri-a). — This little moth (Fig. 342) is very common in our meadows and gardens during the summer and au- tumn months. Its wings are reddish yellow, with the fringes and two trans- verse bands pink. It is found from Maine to Texas. The larva feeds on the common chick-weed, Stellaria media* Family GEOMETRID^; (Ge-o-met'ri-dae). The Green Geometrids (G e-om' e-trids). As a rule the members of this family are bright green in color. And as we have but one other common Geometrid (Dysptcris, p. 286) of this color, the family may be well termed the Green Geometrids. vn, The distinctive structure that characterizes this family is the fact that vein Va of the hind wings arises much nearer to vein V, than to vein V, (Fig. 343). In this family the tendency to expan- sion of the humeral angle of the hind wings, which is exhibited by all Geo- metrina, and which is cor- related with the promi- nent bend into this angle of vein II, characteristic FIG. 343.— Wings of Geometra iridaria. of tllJS SUper-family, IS * This moth is figured and mentioned here because it is one of our most common species, and not as a typical illustration of the Sterrhidae. Il VII, 288 THE STUDY OF INSECTS. carried farther than in the other families (except in the Dyspteris division of the Hydriomenidae). In fact, in all of the forms known to the writer, the humeral angle ex- tends a considerable distance beyond the frenulum. In the fore wings there is also a more marked migration of the base of vein V, towards radius than occurs in other Geometrid families. All these characteristics lead us to consider the Geometridae the most specialized of the Geom- etrina. The Raspberry Geometer, Synchlora glaucaria (Syn- chlo'ra glau-ca'ri-a). — The different species of green Geom- etrids resemble each other to such an extent that it is difficult to describe any one of them in a few words so that it can be surely distinguished. The wings of the Raspberry Geometer are of a delicate pale green color crossed by two lines of a lighter shade, and when expanded measure from one half inch to one inch, there being great variation in size of specimens. The larva is more easily distinguished on account of its curious habits. It feeds on the fruit and foliage of raspberry, but chiefly on the fruit. It covers its body by attaching to it bits of vegetable matter, so that it is masked beneath a tiny heap of rubbish. Family AUZATID^: (Au-zat'i-dae). The Auzatids (Au-za'tids). Only a single species belonging to this family is known to occur in this country. This is a small moth with delicate snow-white wings which expand from three fourths of an inch to one inch. This is Eudeilinea herminiata (Eu-dei- lin'e-a her-min-i-a'ta). In the form of the body and in the structure of the wings (Fig. 344) the members of this family closely resemble the differs in important respects from the typical members of the family, and may belong elsewhere. LEPIDOPTERA. 289 indi- X— -~. ides. I <^ a Drepanidae. As in the Drepanidae vein VII appears to be four-branched, and the course of vein II of the hind wings is similar in the two families, except that in the Auzatidae this vein anastomoses with vein III beyond the discal cell; but the extent of this anastomosis varies greatly in different viduals of our species. In the Auzatidae the apex of the fore wings is not sickle-shaped ; and the branches of radius of the fore wings coalesce as in the Geometridae, ^ — "VITi Veins III3 and III4 COal- FIG. 344.— Wings of Eudetlinea herminiata. escing to near the apex of the wing.* Family DREPANID^; (Dre-pan'i-dae). The Hook-tip Moths. The members of this family are small, slender-bodied moths, which can be easily recognized by the sickle-shaped apex of the front wings (Fig. 345). An approach to this form of wing is pre- sented by some species of the Satur- niidae and by certain Geometrids. But the former are large, stout-bodied moths ; FIG. 345.— putypteryx arcu- and the latter differ in wing venation, cubitus of the fore wings appearing only * In the Drepanidae veins IIIj+» and III4 } » do not coalesce from the apex of the discal cell outward (Figs. 346 and 347); but veins IIIj and II I4 anastomose for a greater or less distance near the apex of the wing, thus forming an accessory cell. 290 THE STUDY OF INSECTS. three-branched with them, whereas it appears four-branched in the Drepanidae (Fig. 346). Although the humeral angle of the hind wings is greatly developed in these moths, some of them retain the frenulum. FIG. 346.— Wings of Oreta rosea. FIG. 347.— Wings of Platypteryx arcuata When the frenulum is present it is borne at the end of a long thickened portion of the wing, so that it is at a con- siderable distance from the point where the wing is attached to the body (Fig. 347).* The larvae are remarkable in having the anal prolegs rudimentary, and the caudal segment prolonged into a more * We class the Drepanidae among the Frenulum-conservers, although many of them have lost the frenulum. Among the true Frenulum-losers the loss of the frenulum occurs while the race is still in a very generalized con- dition, no trace of a frenulum being found among these insects except a rudi- ment in the most generalized forms (Bombyx, Cicinnus). In the Drepanidae, however, the frenulum is retained by very highly specialized forms. There is a striking similarity in this respect between this family and the more specialized Geometrids. LEPIDOPTEKA. 29 1 or less lizard-like tail. They live upon the foliage of shrubs and trees, and transform in a web between the leaves, or in a case in a rolled leaf. Only a small number of species occur in our fauna; at present we know only eight ; and all but one of these pertain to the eastern half of the continent. Our most common Hook-tip Moth is Platypteryx arcu- ata (Pla-typ'te-ryx ar-cu-a'ta). This species is of a dirty white color marked with dark brownish lines and bands as shown in Figure 345. Its larva feeds upon white birch. Pla- typteryx genicula (P. ge-nic'u-la), another eastern species, re- sembles the preceding, but differs in being of a light ochre- yellow color and in the course of the wavy lines on the front wings. A third similar species occurs in California; this is Platypteryx siculifera (P. sic-u-lif'e-ra). Family CYMATOPHORID^E (Cym-a-to-phor'i-dae). The Cymatophorids (Cym-a-toph' o-rids). The Cymatophoridae include moths of medium size, with elongated wings. The front wings are usually slightly widened at the inner angle (Fig. 348), and in our more common species are conspicuously marked with wavy or zigzag lines. The antennae are filiform and more or less velvety or pubescent in the male, and the maxillae are well developed. The moths fly by day, and when at rest fold their wings FlG. ^.- roof-like upon the abdomen. The venation of the wings is illustrated by Figure 349. The important features to be noted are the following: In the front wing vein V, arises midway between veins V, and V3 ; while in the hind wing vein V, arises much nearer to V, than to V,. In the hind wing the subcosta and radius are distinct, and vein V, is joined to radius by a comparatively 292 THE STUDY OF INSECTS. The larvae are naked, nil and long cross-vein (Fig. 349, c. z>.), so that the two appear to separate before the end of the discal cell. In the males the tip of the frenulum is knobbed. live upon the leaves of shrubs and trees. They often con- ceal themselves in a case, made by loosely fastening together leaves, or by folding a single leaf. There are in our fauna rep- resentatives of only four or five genera belonging to this family ; and the species that are common hardly exceed this number. One of the more common species is Thyatira scripta (Thy-a-ti'ra scrip'ta). This has faWtt-COlored front Vll, FIG. 349,-Wingsof Thyatirn scripta conspicuously marked with light bands and zigzag lines (Flg- 348). According to Thaxter, it lays its eggs late in July, in chains of five or six, on the leaves of raspberry, upon which the larvae feed. The mature larva is rich yellow- brown, often almost black, with a distinct dorsal black line. The lateral portions are more yellow with blackish mottlings. When at rest the larva either elevates the cephalic and caudal ends of the body, like the Notodontids, so that the head rests upon the caudal segments, or conceals itself in a case formed by curling down the edge of a leaf. It makes a very slight cocoon late in August. Another common species is Pseudothyatira cymatopho- roides (Pseu-do-thy-a-ti'ra cym-a-toph-o-roi'des). This spe- slightly larger than the preceding one, expanding nearly two inches. The front wings are silky gray tinted with rose. They are marked with a black spot at the base, a double or triple line, forming a black band at the end of LEPIDOPTERA. 293 the basal third of the wing, two black spots on the outer half of the costa, a black spot at the inner angle, and a row of black points on the outer margin. There is a variety which lacks the black band and the four black spots. The larva of this species has been found on red oak ; it is of a rich yellow-brown, mottled with fine dark lines, and lives in a case made by fastening leaves together. It makes a slight cocoon late in September ; the adult emerges in June. Family NOCTUID^: (Noc-tu'i-dae). The Owlet-moths or Noctuids (Noc1 tu-ids). This is the largest of all of the families of the Lepidop- tera ; more than eighteen hundred species are now known to occur in America north of Mexico. The great majority of the moths that fly into our houses at night, attracted by lights, are members of this family. The nocturnal habits of these insects, and the fact that often when they are in obscurity their eyes shine brightly, have suggested the name of the typical genus (Noctua, from the Latin for owl), as well as the popular name Owlet-moths, by which they are known. Similar popular names have been given to them in several other languages, Although there is almost no question regarding the lim- its of this family, as yet no structural character has been found by which they can be distinguished from certain other moths. Neither is there a general uniformity of appearance which we can use for this purpose, as the family includes great variations in size, form, and coloring. But most of the species are dull-colored moths of medium size. The greatest difficulty arises in attempting to separate this family from the three following. Of these the first two (Pericopidae and Agaristidae) differ in their highly contrast- ing colors, as pointed out in the analytical table (p. 212, N and NN). In the third of these families (Lymantriidae) the species have pectinate antennae and do not have ocelli. 294 THE STUDY OF INSECTS. Only a few Noctuids have pectinate antennae, and these, so far as they are known to the writer, lack ocelli. The venation of the wings of a member of this family is represented by Fig- ure 350. Vein V, of the fore wings arises much nearer to vein V3 than to vein V, ; there is usually an accessory cell ; and the anal vein may be forked towards the base or not. On the hind wings veins II and III usually coalesce for a short distance near the base of the wing; vein V4 may be either FIG. 350.— Wings of Agrotis ypsilon. well preserved or much weaker than the other veins; and there is considerable variation in the point of origin of this vein. In the typical Noctuids, the body is large in proportion to the size of the wings ; the front wings are strong, some- what narrow, and elongated, the outer margin being shorter than the inner margin ; and when at rest, the wings are folded upon the abdomen, giving the insect a triangular out- line. The antennae are thread-like, fringed with hairs, or brush-like, rarely pectinate in the males. Two ocelli are al- most always present. The labial palpi are well developed, and in some species quite prominent. The maxillae are quite long and stout in most species. The thorax is heavy and stout. In some species the scales on the dorsal surface of the thorax are turned up more or less, forming tufts. LEPIDOPTERA. 295 The abdomen is conical and extends beyond the inner angle of the hind wings, when these are spread. The majority of the larvae are naked, of dull colors, and provided with five pairs of prolegs. As a rule they feed on the leaves of plants, but some are borers and some gnaw into fruits. Among them are some of the most important insects injurious to agriculture. Although the Noctuidae is a very large family, the efforts that have been made to divide it into subfamilies have not given satisfactory results. Many subfamilies have been in- dicated ; but in most cases these proposed subfamilies appear to be merely groups of allied genera which cannot be dis- tinguished by any common character from the other similar groups. In the following pages we have given illustrations of a large proportion of these groups, in order to show,- as well as we can in a limited space, the variations in form in- cluded in this family. The sequence of groups adopted is that given in the latest catalogue of the family, that by Pro- fessor J. B. Smith ; in some respects we doubt its being natural. There is a group of moths, the Deltoids, which are placed at the foot of this family on account of their apparent re- lationship to the Geometrids and to the Pyralids. These moths are usually of dull colors and of medium size. The name Deltoids was suggested by the triangular outline of the wings when at rest, which is well represented by the Greek letter delta. When in this position the wings slope much less than with other Noctuids, the attitude being more like that assumed by the Geometrids ; but the hind wings are more nearly covered than with the Geometrids. Many of the Deltoids have very long palpi, resembling in their size those of the Pyralids. The Clover Hypena, Hypena scabra (Hy-pe'nasca'bra), is a common Deltoid. The larva feeds on the leaves of clover, and is a slender green worm. It measures when full grown two-thirds inch in length and only about one-tenth inch in 296 THE STUDY OF INSECTS. width in its widest part ; it has a narrow subdorsal whitish line and a lateral one of the same color. When ready to transform it webs together several leaves and passes the pupa state in the nest thus made. The adult (Fig. 35 1) is a blackish, brown moth, with an irregular grayish shade on the outer half of the fore wings, and with very broad hind wings. The palpi, which are not well shown in FIG. ^.-Hypena scab™, the figure, are long, wide, and flat- tened ; they project horizontally like a snout. The Hop-vine Hypena, Hypena humuli (H. hu'-mu-li), is closely allied to the preceding and has often been con- founded with it. The larva feeds on the leaves of hop, and is sometimes a serious pest. One of the most abundant of our Deltoids is Pseu- daglossa lubricalis (Pseu-da-glos'sa lu- bri-ca'lis.) In this species (Fig. 352) the fore wings are chocolate-brown, crossed with yellowish lines; the hind wings are much lighter. The palpi are long; but they are curved overFlGt &-p^f?/°*sa luM- the head, so that they appear short when seen from above, as represented in the figure. The larva feeds on grass. Next to the Deltoids there is placed a group of moths which may be called the Similar-winged Owlets, from the fact that both pairs of wings are similarly marked by trans- verse lines. The group includes the largest of our Noctuids. ^^^^ \ i ^dflft Tlie two f°U°wmg species H^^^L— ^l^tf| I wiU serve to illustrate this 'VN ^fe^k^l |y group. ^^' The Lunate Similar- <£;; ^^ wing, Homoptera lunata *^s^ ^^ '^ (Ho-mop'-te-ra lu-na'ta.) — This is a brownish moth FlG- 353-— Homoptera lunata. with marbled wittgS. It varies greatly in its markings. Figure 353 represents a LEPIDOPTEKA. 297 variety which has been named cdusa, and which does not show well the lunate mark on the hind wings that probably suggested the name of the species. The larva feeds on the leaves of rose, willow, maple, plum, and other plants. The Black Witch, Erebus odor a (Er'e-bus o-do'ra).— The most magnificent in size of our Noctuids is this species (Fig. 354). There is much variation in the depth of coloring. The specimen figured is a female ; in the male the fore wings are more pointed at the apex and the median band is FIG. 354. — Erebus odor a. indistinct. It is a native of the West Indies, and is not known to breed in the United States. But specimens are found as far north as Canada and west to Colorado, and even in California. It is believed that these specimens have flown north from Cuba or from Mexico. Recently some observations have been made which seem to indicate that the moth does breed within our territory ; but the question is not yet settled. Only isolated specimens are found in the North, and these in late summer or autumn. 298 THE STUDY OF INSECTS. Closely allied to the moths just described is another group ^^^ , ^^^ of species with broad wings, of jffife^Xn/^^i^HB 1 which the Two-lined Parallelia, pp^Jgi^^ «r Parallelia bistriaris (Par-al-lel'i-a bi-stri'a-ris) is a good example. ^Sr This moth (Fig. 355) is brown- ^^Br JB ^Iss^ jgh jn Color, and has the fore FIG. 3K.-paraiMia butriaris. wmgs crOssed by two parallel lines. The larva feeds on the leaves of maple. The most striking in appearance of the Noctuids, if we except the Black Witch and one or two allied species, are the moths belonging to the genus Catocala (Ca-toc'a-la). These moths are of large size, often expanding three inches or more. The fore wings are usually brown or gray, marked with wavy or zigzag lines. The ground-color of the hind wings is black; but in many species these wings are con- spicuously banded with red, yellow, or white. This pecu- liarity has suggested the name Underwings by which these insects are commonly known in England. The genus is a very large one ; about eighty species are now known from this country; and many of these are extremely variable, so that about twice that number of named forms are now recognized. The Ilia Underwing, Catocala ilia (C. il'i-a), will serve as an example (Fig. 356). The larvse of the LEPWOPTERA. 2. £. \ • Hi MI FIG. 360. — Plusia simplex. (rig. 360) is a well-known illustra- tion of this genus. About sixty species of this genus have been described from North America. In some of the species the metallic markings cover a large proportion of the fore wings, and in others they are wanting. The larva of Plusia brassicce (P. bras'si-cae) feeds on cabbage and other Cruciferce. In the cotton-growing States the most important insect pest is the Cotton-worm, Aletia argillacea (A-le'ti-a ar-gil-la'- ce-a). The adult of this insect (Fig. 361) is a brownish \ / moth with its fore wings crossed fcj^^-^iix^l^JBJp with wavy lines of darker color and ^ffS^SjfljSf marked with a bluish discal spot |^f and two white dots as shown in the figure. This moth is found in the Northern States and even in FIG. 36i.-AMfa argiiiacea. ^^fa jn the latter part of the summer and in the autumn. But this occurrence in the North is due to migrations from the South, as the insect can- not survive the winter north of the Gulf States. The larva feeds on the foliage of cotton ; and as there are five or six generations in a year, the multiplication of individuals is very rapid, and the injury to the cotton great. Detailed descriptions and colored figures of this insect in its different stages are given in the works cited above in the description of the Boll-worm. The best known way of combating this pest is by the use of Paris green. 3O2 THE STUDY OF INSECTS. The Hooded Owlets, Cucullia (Cu-cuTli-a). — We have several common grayish moths, in which the fore wings are marked with numerous irregular dashes of dark color, and -v _—-^^^ *n which the thorax is furnished ^SSto^m&^^&^f with 3- prominent tuft of scales. These moths belong to the genus Cucullia. Figure 362 represents Cucullia speyeri (C. spey'er-i). P These insects evidently have FIG. 362 .-Cucuina speyeri. the power of moving this tuft of scales ; for sometimes it projects forward over the head as shown in the figure, while in other specimens of the same species it will be directed backward ; in this case it is much less conspicuous. The larvae of the Hooded Owlets feed upon the leaves of goldenrod and other Compositae. The Scalloped Owlet, Scoleopteryx libatrix (Scol-e-op'ter- yx li-ba'trix). — This moth is easily recognized by the shape of the wings, the outer margins of which are deeply cut and scalloped (Fig. 363). The color of the fore wings is soft brownish gray, slightly pow- dered with rust - red, and frosted with white along the costa. There is an irregular FIG. 363.— Scot^piiryx patch of rust-red reaching from the base to the middle of the wing, a single, white, transverse line before the middle, and a double one beyond the middle. The larva feeds on willow. This species is found in all parts of the United States and in Europe. The American Copper Hind- wing, Ainphipyra pyramidoides (Am-phip'y-ra pyr-a-mi-doi'des). FIG. Tfx.-Amphipyra Pyramidoides. —The fore wings of this moth (Fig. 364) are dark brown, shaded with paler brown, and with dots and wavy lines of a glasey gray or dull whitish LEPIDOP TERA . 303 hue. The hind wings, except the costal third, are reddish, with more or less of a coppery lustre. This suggests the popular name. A closely-allied species found in Europe is known as the Copper Underwing ; but we prefer to reserve the name Underwing for the species of Catocala. The larva feeds on the leaves of grape and Virginia-creeper. The Many-dotted Apple-worm, Balsa malana (Bal'sa ma-la'na). — In June, and again in August or September, there is some- times found on apple-leaves, in considerable numbers, a rather thick, cylindrical, light-green worm, an inch or more in length, FIG. 365 - , . , Balsa malana. with fine, white, longitudinal lines and numerous whitish dots. These are the larvae of the little moth represented by Figure 365. The fore wings of this moth are ash-gray, marked by irregular, blackish lines. The larvae feed on the leaves of many other trees besides apple. The moth has been found throughout the eastern half of-our country. The Army-worm, Leucania unipuncta (Leu-ca'- ni-a u-ni-punc'ta). — The Army-worm is so called because it frequently appears in great numbers, and, after destroying the vegetation in the field where the eggs were laid, marches like an army to other fields. This insect occurs throughout the United States east of the Rocky Mountains, and is present every year; but it attracts attention only when it appears in great numbers. The larva (Fig. 366) is one and one-half inches long when VLeucan~a fulf grown, and is striped with black, yellow, and w"iarMi'"' green. The adult is of a dull brown color, marked in the center of each fore wing with a distinct white spot (Fig. 367). In seasons of serious outbreak of this pes usually appears first in limited areas, in meadows or pastures. 304 THE STUDY OF INSECTS. If it is discovered before it has spread from these places it can be confined by surrounding the field with a ditch, or it may be destroyed by spraying the grass with Paris-green water. Ordinarily, however, the worms are not observed until after they have begun to march and are wide-spread. In such cases it is customary 'VN^ N&\ to protect fields of grain in their path by surrounding them with ditches with ver- tical sides; it is well to dig ViG.&.-Leucaniaunifuncta. holes like pOSt-holeS at in- tervals of a few rods in the bottom of such ditches. The worms falling into the ditch are unable to get out, and crawl along at the bottom and fall into these deeper holes. We have seen these insects collected by the bushel in this way. The Diver, Bellura gortynides (Bel-lu'ra gor-tyn'i-des). — One of the most remarkable exceptions to what are usually the habits of members of this order is presented by the larva of this species. This larva is able to descend into water and remain there for a long time. It lives in the leaf- stalks of the pond-lily. It bores a hole from the upper side of the leaf into the petiole, which it tunnels in some instances to the depth of two feet or more below the surface of the water. This necessitates its remaining below the surface of the water while feeding. The writer has seen one of these larvae remain under water FlG- &--Beiiura voluntarily for the space of a half-hour. The tracheae of these larvae are unusually large, and we believe that they serve as reservoirs of air for the use of the insect while under water. The form of the hind end of the larva has also been modi- LEPIDOPTERA. 305 fied, so as to fit it for the peculiar life of the insect. The last segment appears as if the dorsal half had been cut away; and in the dorsal part of the hind end of the next to the last segment, which, on account of the peculiar shape of the last segment, is free, there open a pair of spiracles much larger than those on the other segments. When not feeding the larva rests at the upper end of its burrow, with the segment bearing these large spiracles projecting from the water. The adult insect is a brownish moth which varies greatly in size and markings. Figure 368 represents what seems to be the more common form. The Zebra. Caterpillar, Mamestra picta (Ma-mes'tra pic'ta). — Cabbage and other garden vegetables are often subject to the attacks of a naked caterpillar, which is of a light yellow color, with three broad, longitudinal, black FIG. 369.— Mamestra picta, larva. FIG. 370.— Mamettra picta, stripes, one on each side and the third on the top of the back. The stripes on the sides are broken by numerous pure white lines (Fig. 369). It passes the winter in the pupa state. The adult (Fig. 370) has dark chestnut-brown fore wings and pale yellowish hind wings. Cut-worms. — Few pests are more annoying than the ras- cally little harvesters that nightly, in the spring, cut off our corn and other plants before they are fairly started. There are many species of these cut-worms, but they are all the larvae of Owlet-moths. In general their habits are as follows: The moths lay their eggs during midsummer. The larvae soon hatch, and feed upon the roots and tender shoots of herbaceous plants. At this time, as the larvae are small and their food is abundant, they are rarely observed. On the 306 THE STUDY OF INSECTS. approach of cold weather they bury themselves in the ground and here pass the winter. In the spring they renew their attacks on vegetation ; but now, as they are larger and in cultivated fields the plants are smaller, their ravages quickly attract attention. It would not be so bad if they merely destroyed what they eat ; but they have the unfortu- nate habit of cutting off the young plants at the surface of the ground, and thus destroy much more than they consume. They do their work at night, remaining concealed in the ground during the daytime. When full grown they form oval chambers in the ground in which they pass the pupa state. The moths appear during the months of June, July, and August. There are some exceptions to these generalizations : some species of cut-worms ascend trees during the night and destroy the young buds ; some pass through two generations in the course of a year ; and a few pass the winter in the pupa state. Cut-worms can be destroyed by poisoned baits of fresh clover or 9ther green vegetation, or with poisoned dough made of bran. Much can be done by making holes in the ground with a sharpened stick, as a broom-handle. The holes should be vertical, a foot deep, and with smooth sides. On the approach of day the cut-worms will crawl into such holes to FIG. yi\.—Noctua c-nigru»t. hide, and will be unable to crawl out again. Climbing cut-worms can be jarred from the trees during the night, and caught upon sheets, and then destroyed. One of our cut-worms, which is known as the Spotted Cut-worm, is the larva of the Black-c Owlet, Noctua c-mgrum (Noc'tu-a c-ni'grum). This moth (Fig. 371) is one of the most common species attracted to lights. It occurs throughout our country and in Europe. At the end of the Noctuid series there is placed a group LEPIDOPTERA. 307 of genera, which contain species that differ in appearance from other Noctuids, the larvae of many being hairy like those of Arctiids. The fore wings of the moths are gener- ally light gray with dark spots, and in many species have a dagger-like mark near the anal angle. On this account these moths have received the name Daggers. The Ochre Dagger, Acronycta morula (Ac-ro-nyc'ta mor'u- la). — This moth (Fig. 372) is pale gray with a yellowish tinge. Besides the black line forming part of the dagger near the anal angle of the fore wing, there is a similar black line near the base of the wing, and a third near the outer margin between _ _ ITT TM i FlG. 372. — Acronycta morufa. veins V, and Va. The larva feeds on elm and bassvvood. When full grown it is mottled brown and greenish like the bark, it is clothed with but few scattered hairs, and has a hump on the first, fourth, and eighth abdominal segments. The American Dagger, Ac- ronycta ainericana (Ac-ro-nyc'- ta a-mer-i-ca'na). — This is a gray moth resembling in its general appearance the pre- ceding, but with the black lines on the fore wings much less distinct. Its larva, how- ever, is very different (Fig. 373). This larva looks like an Arctiid, being densely clothed with yellow hairs. But these hairs are scattered over the surface of the body instead of growing from tubercles, as with the larvae of Arctiids. Along 308 THE STUDY OF INSECTS. the sides of the body and at each end are a few scattered hairs that are longer than the general clothing, and there are two pairs of long black pencils borne by the first and third abdominal segments, and a single pencil on the eighth abdominal segment. When at rest the larva remains curled sidewise on a leaf, as shown in the figure. It feeds on maple, elm, and other forest trees. The Witch-hazel Dagger, Acronycta Jiamamelis (Ac-ro- ^^^^^^^ nyc'ta ham-a-me'lis). — In the latter ^^^^ part of summer and in autumn the *•<**: BJ^ larva of this species is common on the Cy>*ji ^w leaves of witch-hazel, oak, and other HHBp forest trees. It differs greatly in ap- ^1 pearance from the preceding species, being nearly naked (Fig. 374). When at rest it usually lies curled as shown TSHBT in the figure. It varies in color from light yellow to reddish brown. Its most characteristic feature is a double ™m*nZ\2£ ha'"a~ row of milk-white spots along the middle of the back. Family LYMANTRIID^; (Lym-an-tri'i-dae). The Tussock-mot/is. The larvae of these moths are among the most beautiful of our caterpillars, being clothed with brightly-colored tufts of hairs ; and it is to this characteristic clothing of the larvae that the popular name Tussock-moths refers. The adult moths are much plainer in appearance than the larvae : and in the genus Notolophus, to which our most common species belong, the females are practically wingless, the wings being at most short pads, of no use as organs of flight. The Tussock-moths are of medium size, with the antennae of both sexes when winged pectinated, those of the males LEPIDOPTEKA. 309 m, in, very broadly so ; the wingless females have serrate or nar- rowly pectinate antennae. The ocelli are wanting. The legs are clothed with woolly hairs; when the insect is at rest the fore legs are usu- ally stretched for- ward, and are very conspicuous on ac- count of these long hairs. The venation of the wings is rep- resented by Figure 375 ; in this respect these moths are very similar to the Noc- tuids ; in fact we have been unable to find as yet any con- stant feature in the structureof the wings FlG- 375-— wings of Notohpkus of either family that will serve to separate the two. But in the Lymantriidae the antennae are pectinate and the ocelli are absent ; while in the Noctuidae the antennae are usually sim- ple and the ocelli are usually present; and when the antennas are pectinate the ocelli, in all cases known to us, are pres- ent : in this way a distinction is preserved between the two families. Although it is hard to find a distinction betw.een the two that can be put into words, the general appearance of the Tussoxrk-moths is very different from that of the Noctuids, and entomologists have no difficulty in deciding to which family any species belongs. The Tussock-moths are chiefly nocturnal ; but the males of Notolophus fly in the daytime. The larvae of our native species are very characteristic in appearance. The body is hairy; there are several con- 3IO THE STUDY OF INSECTS. spicuous tufts of hairs on the dorsal aspect of the abdomen, and at each end of the body there are long pencils of hairs ; on the sixth and seventh abdominal segments there is on the middle of the back of each an eversible gland supposed to be a scent-organ similar to the osmateria in the larvae of Papilio, and it is stated that a fine spray of liquid is some- times thrown from them. Excepting a few rare forms, our native species fall into two genera — Notolophus and Parorgyia. In Notolophus the males have short, broad wings ; the females are nearly wingless. In Parorgyia both sexes are winged, and the wings are relatively longer than in Notolophus. Our most common species belong to Notoloplius. Of this genus the three best-known species are the following : — The White-marked Tussock-moth, Notolophus leucostigma (No-tol'o-phus leu-co-stig'ma). — This is our most common rep- resentative of the family. It frequently °ccurs in such great numbers that it seriously injures the foliage of shade- trees and orchards. The male (Fig. F,C. 3, - stigma. wings are crossed by undulated bands of darker shade and bear a conspicuous white spot near the anal angle. The female is white and resembles a hairy grub FIG. 377.— Notolophus leucostigma, larva. more than a moth. She emerges from her cocoon and after pairing lays her eggs upon it, covering them with a LEPID OP TERA . 3 I I frothy mass. The larva (Fig. 377) is one of the most beau- tiful of our caterpillars. The head and the glands on the sixth and seventh abdominal segments are bright vermilion- red. There is a velvety black dorsal band, bordered with yellow subdorsal stripes ; and there is another yellow band on each side just below the spiracles. The prothorax bears on each side a pencil of long black hairs with plume-like tips; a similar brush is borne on the back of the eighth abdominal segment, and the first four abdominal segments bear dense brush-like tufts of cream-colored or white hairs. When this insect becomes a pest the larvae can be de- stroyed by spraying the infested trees with Paris-green water ; or the egg-bearing cocoons can be collected during the win- ter and destroyed. These cocoons are attached to the trunks of the trees and to neighboring objects, or to twigs. In the latter case they are usually partially enclosed in a leaf. Co- coons not bearing eggs should not be destroyed, as many of them contain parasites. Owing to the wingless condition of the female this pest spreads slowly. The Well-marked Tussock-moth, Notolophus definita (N. def-i ni'ta). — The male, like that of the preceding species, is of an ashy gray color ; but the markings of the fore wings are much more distinct. The female is light brown. She lays her eggs in a mass on her cocoon, covering them with hair from her body. The larva closely resembles the pre- ceding species in the form and arrangement of its tufts of hair, but differs markedly in color, being almost entirely light yellow. There is a dusky dorsal stripe and a velvety black spot behind each of the tufts of the first four abdominal seg- ments. The head and the glands on the sixth and seventh abdominal segments are, like the body, light yellow. The Old Tussock-moth, Notolophus antiqua (N. an-ti'qua). —The male is of a rust-brown color ; the fore wings are crossed by two deeper brown bands and have a conspicuous white spot near the anal angle. The body of the grub-like female is black, clothed with yellowish white hairs ; she lays 312 THE STUDY OF INSECTS. her eggs on her cocoon, but, unlike the two preceding species, does not cover them with anything. The larva differs from either of the preceding in having an extra pair of pencils of plume-like hairs arising from the sides of the second abdominal segment ; the head is jet-black ; the glands on the sixth and seventh abdominal segments are vermilion-red or sometimes bright orange ; and the tubercles on the sides of the back of the second and third thoracic and the sixth and seventh abdominal segments are orange-red or yellow margined with pale yellow. The Gipsy M.o\h,Porthetria ^y/dr(Por-the'tri-a dis'par). — This is a European species which has been introduced into Massachusetts. It has become such a serious pest that the Legislature of that State has appropriated a large sum of money to be expended in efforts to eradicate it ; this work is now going on. The male is yellowish brown ; the female, white (Fig. 378). In each the fore wings are crossed by many dark lines and bear a black lunule on the discal vein. The specimen figured is unusually small. The eggs are laid in a mass on any convenient object and are covered with hair from the abdomen of the female. The larva differs greatly in appearance from that of the preceding genus, lacking the peculiar pencils and tufts of hair ; but the characteristic glands of the sixth and seventh abdominal segments are present and are red. The body is dark brown or black, finely reticulated with pale yellow, and with narrow yellow dorsal and subdorsal lines. On the dorsal aspect of each segment there is a pair of prominent, rounded tubercles bearing spiny black hairs. The first five pairs of these tubercles are bluish, the others dark crimson-red. There are also two rows of tubercles on each side of the body which bear longer hairs. LEP1DOPTERA. 3'3 Family AGARISTID^: (Ag-a-ris'ti-dae). The Wood-nymph Moths. These gayly-dressed moths are a delight to the collector. We have but few species of them in this country, and an even smaller number are common. These moths are either black with large, white or yellow, rounded patches upon the wings, or they have the front wings white, margined with brown, and the hind wings pale yellow. They are chiefly day-flying; but some of them are attracted to lights at night. The shape of the antennae varies greatly in the different genera. In Euthisanotia the antennae are fili- form ; in Alypia slightly enlarged near the tip ; and in Psychomorpha they are filiform in the female and pectinated in the male. The max- illae are moderately well developed and spirally rolled. The venation of the wings (Fig. 379) is very similar to that of some Noctuids ; but there is no difficulty in separating the two fam- ilies, the Wood-nymph Moths being very dif- FIG. 379.- wings of ferent in appearance from any Noctuids. The larvae are but slightly clothed, and live exposed on the leaves of plants. Our more common species feed chiefly on grape and Virginia-creeper, which they some- times injure to a serious extent. In such cases they can b destroyed by the use of Paris green. This substance can 314 THE STUDY OF INSECTS. be used even in vineyards in the East, as the application would have to be made early in the season, and the sum- mer rains would wash the poison from the vines. The pupa state is passed either in an earthen cell or in a very slight cocoon. The family is one of limited extent ; less than thirty North American species are known. The larger number of these occur in the far West or in the Gulf States. The following are the most common species : — The Eight-spotted Forester, Alypia octomactilata (A-lyp'- i-a oc-to-mac-u-la'ta). — This species is of a deep velvety-black color. The front wings have two large sulphur-yellow spots ; and the hind wings, two white spots (Fig. 380). The figure represents a male ; the female is some- what larSer' The Patagia are sulphur- yellow. The legs are black with orange- colored scales on the tibiae of the first and second pairs. The larva (Fig. 381) feeds upon the leaves of grape and Vir- ginia-creeper, and sometimes occurs in such large numbers as to do serious injury. The ground-color of the larva is white, with eight black stripes on each segment, and a FIG. 381.— Alypia octomaculata, larva. broader orange band, bounded by the two middle stripes ; the orange bands are marked by black, conical, elevated spots. There are usually two broods each year, the moths appearing on the wing in May and August, the caterpillars in June and July, and in September. The pupa state is passed in an earthen cell in the ground. Langton's Forester, Alypia langtonii (A. lang-to'ni-i), resembles the preceding species in general appearance, but LEP1DOP TERA . 315 can be readily distinguished by the hind wings bearing only a single spot. It is not a common species, and its early stages have not yet been described. The Grape-vine Epimenis, Psychomorpha epimenis (Psy- cho-mor'pha ep-i-me'nis). — This is a velvety-black species with a large white patch on the outer third of the front wings and a brick-red patch on the hind wings (Fig. 382). The larva resembles somewhat that of Alypia figured above; but it is bluish and has only four light and four dark stripes to each segment. F:c It feeds upon the terminal shoots of grape and Virginia-creeper in spring, drawing the leaves to- gether by a weak silken thread and destroying them. When ready to transform, which is usually towards the end of May, it either enters the ground or bores into soft wood to form a cell. Within this it remains until the following spring. The Beautiful Wood-nymph, Enthisanotia grata (Eu-this- a-no'ti-a gra'ta). — This moth (Fig. 383) well deserves the popular name that has been applied to it. Its front wings are creamy white, with a glassy surface ; a wide brownish- purple stripe extends along the costal margin, reaching from the base to a little beyond the middle of the wing, and on the outer margin is a band of the same hue, which has a wavy white line running through it, and is margined internally with a narrow olive-green band. FIG. ^.—Euthisanotia. grata. Qn j.J.,e jnner margin JS B, yel- lowish olive-green cloud. The hind wings are clear pale ochre-yellow, with a brown band on the outer margin. The wing expanse is about one and three-fourths inches. The moth appears during the latter part of June or early in July. The larva of this species is pale bluish, crossed by bands of orange and many fine black lines. It also bears a THE STUDY OF INSECTS. resemblance to that of Alypia, but may be distinguished by having only six transverse black lines on each segment. It has the same food-plants as the species described above. It transforms in a cell in the ground or in soft wood. The Pearl Wood-nymph, Euthisanotia unto (E. u'ni-o). — This moth closely resembles the species just described, but is smaller, expanding a little less than one and one half inches. The outer border of the front wings is paler and mottled ; and the band on the hind wings extends from the inner angle to the apex. The larva resembles that of E. grata ; it feeds upon the leaves of Euphorbia coloratum, and perhaps on grape also. Family PERICOPID^E (Per-i-cop'i-dae). The Pericopids (Pe-ric' o-pids}. These beautiful insects occur within the limits of our country only in the far West and in the Gulf States. They resemble the ™,J%^\L Wood-«ymPh Moths in their strongly contrast- ing colors; but can be distin- guished from them by the po- sition of the ori- gin of vein V, of the hind wings, which appears to be a branch of cubitus (Fig. 384). Our most com- mon species be- long to the genus Gnophala (Gno- F,G. 384 -Wings of Gnophvla hopfferi. phse'la). TllCSC black with conspicuous yellow spots. G. vermiculata are LEPIDOPTERA. 317 Colorado ; it is represented FIG. ^.— (G. ver-mic-u-la'ta) occurs by Figure 385. G. hopf- feri (G. hopf'fe-ri) is found in California, in the foot-hills of the Sierra Nevadas. It has three yellow spots near the mid- dle of the fore wing, and a transverse row of from three to five spots near the outer margin ; on the hind wings there are two spots near the base and another pair between these and the apex of the wing. Family ARCTIID^: (Arc-ti'i-dae). The Tiger-moths, or Arctiids (Arc' ti-ids). The Arctiidae includes stout-bodied moths, with moder- ately broad wings, which in the majority of cases are con- spicuously striped or spotted, suggesting the popular name Tiger-moths ; some of the species, however, are unspotted. A large proportion of the species are exceed- ingly beautiful ; this renders the family a favorite one with collec- tors. As a rule, when at rest, the wings are folded roof-like upon the body. The moths fly at night, and are at- tracted to lights. These moths differ from the following fam- jn haying ocem. these are often prominent, at other times they are difficult to see on account of the long hairs with which the head is THE STUD Y OF INSECTS. clothed. The palpi are short, usually but little developed ; and the maxillae are present. The most important features in the venation of the wings (Figs. 386, 387) is the union of veins Va and V, of the fore wings with cubitus, making it apparently four-branched ; and the growing together of subcosta and radius of the hind wings for a considerable distance. The extent of the union of these two veins varies greatly in the different genera; but so far as we have ob- served it is always less Trrj:r4 than four fifths of the length of the discal cell. This character is of use in separating these insects from the Zygaenidae in which the union of these two veins is carried farther. The larvae of the Tiger-moths are clothed with dense clusters of hairs. In fact a large proportion of our com- mon hairy caterpillars are members of this FIG. 387.— Wings of Pygoctenucha funerea. family. In some species, certain of the clusters of hairs are much larger than the others, resembling in this respect the clothing of the Tussock-moths. Most larvae of the Arctiids feed upon herbaceous plants, and many species seem to have but little choice of food-plant ; but certain common species feed upon leaves of forest- trees. About one hundred and fifty North American species have been described. The following are some of the more common representatives. Among the more beautiful of the Tiger-moths is a genus the species of which are snow-white or light yellow with the LEPIDOPTERA. 3*9 In most species the fore wings banded with dark brown. hind wings are unspot- ted and are snow- white, but in some the hind wings are yellow. These moths constitute the genus Haploa (Hap'lo-a). A species common in the Atlantic States and rep- resented by Figure 388 is Haploa contigua (H. con-tig'u-a). The insects of this genus vary greatly in their markings. The Bella-moth, Utetheisa bella (U-te-thei'sa bel'la) is a whitish moth with lemon-yellow or orange-colored fore wings, crossed by six transverse white bands, each containing a series of black dots (Fig. 389); the FIG. iSg.- > black outer margin, which is bordered within by a narrow white line. The species occurs throughout the Atlantic States. The Harlequin Milkweed Cater- pillar, Cycnia egle (Cyc'ni-a eg'le). — This larva is the most common cat- erpillar found on milkweed. It is clothed with tufts of orange, black, and white ; those at each end of the body are longer than the others, F'r- 39«>.-c>c*/«i «*. 'arva and are arranged radiately (Fig. 390). When full grown 320 THE STUDY OF INSECTS. the larva makes a felt-like cocoon composed largely of its hairs. The adult has mouse-gray, unspotted wings ; the abdomen is yellow, with a row of black spots along the middle of the back. The Hickory Tiger-moth, Halisidota carya (Ha-lis-i- do'ta ca'ry-ae). — One of the most abundant of caterpillars in the Atlantic States and westward during the months of August and September is one clothed with dense tufts of finely barbed white hairs (Fig. 391) ; there is a ridge or crest FIG. 391.— Halisidota carya . larva. of black hairs on the middle of the back of the abdominal segments, a few long white hairs projecting over the head from the thorax, and others projecting back from the last seg- ment ; there are also two pairs of pencils of black hairs, one on the first and one on the seventh abdominal segment, and a similar pair of pencils of white hairs on the eighth abdominal segment. This larva feeds on hickory, FIG. w.-Haiisidcta cary* butternut, and other forest-trees. Its grayish cocoons, composed >st entirely of the hair of the larva, are often found under stones, fences, and other similar places. The fore wings of ie adult (Fig. 392) are dark brown spotted with white. LEPIDOPTERA. 321 The Salt-marsh Caterpillar, Estigmene acrcea (Es-tig-me'ne a-crae'a). — The popular name of this insect was given to it by Harris, and was suggested by the fact that the salt- marsh meadows about Boston were overrun and laid waste in his time by swarms of the larvae. But the name is mis- leading, as the species is widely distributed throughout the United States. The moth (Fig. 393) is white, marked with yellow and black. There are many black dots on the wings, a row of black spots on the back of the abdomen, another row on the venter, and two rows on each side. The sexes differ greatly in the ground-color of the wings ; in the female, this is white throughout ; in the male, only the upper surface of the fore wings is white, the lower surface of the fore wings and the hind wings above and below being yellow. The num- ber and size of the Black spots on the wings vary greatly. There are usually more submarginal spots on the hind wings than represented in our figure. The Fall Web-\vorm, Hyphantria cunea (Hy-phan'tri-a cu'ne-a). — A very common sight in autumn in all parts of our country is large ugly webs enclosing branches of fruit or forest trees. These webs are especially common on apple and on ash. Each web is the residence of a colony of larvae which have hatched from a cluster of eggs, laid on a leaf by a snow-white moth. There is a variety of this moth in which the fore wings are thickly studded with dark brown spots. Every gradation exists between this form and those that are spotless. The species winters in the pupa state, and the moths emerge during May or June. The webs made by this insect should not be confounded with those made by the Apple-tree Tent-caterpillar. The webs of the Fall Web-worm are made in the autumn, and 322 THE STUDY OF INSECTS. are much lighter in texture, being extended over all of the leaves fed upon by the colony. The Isabella Tiger-moth, Pyrrharctia Isabella (Pyr-rharc'- ti-a is-a-bel'la).— " Hurrying along like a caterpillar in the fall" is a common saying among country people in New England, and probably had its origin in observations made upon the larva of the Isabella Tiger-moth. This is the evenly clipped, furry caterpillar, reddish brown in the middle and black at either end, which is seen so commonly in the autumn and early spring (Fig. 394). Its evident haste to get somewhere, in the autumn, is almost painful to witness. A nervous anxiety is apparent in every undulat- ^. ^.-Pyrrharctia nabella, larva. jng movement Qf its body . and frequently its shining black head is raised high in the air, and moved from side to side, while it gets its bearings. Occasionally after such an observation it evidently finds it is mistaken, and turns sharply and hastens along faster than ever in another direction. So far as we can judge, its ex- citement comes from a sudden fear that winter will over- take it before it can find a cosy, protected corner in which to pass its winter sleep. In the spring it comes forth again, and after feeding for a time makes a blackish-brown cocoon composed largely of its hair. The adult is of a dull grayish tawny-yellow, with a few black dots on the wings, and fre- quently with the hinder pair tinged with orange-red. On the middle of the back of the abdomen there is a row of about six black dots, and on each side of the body a similar row of dots. The Yellow-bear, Spilosoma virginica (Spil-o-so'ma vir- gin'i-ca). — The larva of this species is one of the most com- mon hairy caterpillars found feeding on herbaceous plants. It was named by Harris the Yellow-bear on account of the long yellow hairs with which the body is clothed. These hairs are uneven in length, some scattered ones being twice LEPIDOPTERA. 323 as long as the greater number of hairs. The long hairs are more numerous near the caudal end than elsewhere, but are nowhere gathered into pencils as with the Tussock-cater- pillars. This larva varies greatly in color. The body is most often of a pale yellow or straw color, with a black, more or less interrupted, longitudinal line along each side, and a more or less distinct transverse line of the same color be- tween each of the segments. Sometimes the hairs are foxy red or light brown, and the body brownish or even dark brown. The head and the ends of the feet and forelegs are yellowish, and the venter is dusky. The larva feeds on almost any plant. The cocoon is light, and is composed almost entirely of the hairs of the caterpillar. This insect passes the winter in the pupa state ; and it is probable that there are usually two or more broods each year ; but these are not well marked. The moth (Fig. 395) is snowy white, with the wings marked by a few black dots ; these vary in num- ber, but there are rarely more than three on either wing. There is a row of black spots on the back of the abdomen, and another on each side, and between these a longitudinal deep yellow stripe. A very large number of species of Tiger-moths belong to the genus Eyprepia (Ey-pre'pi-a). These are perhaps the most striking in appear- ance of all members of the family. The fore wings are velvety black marked with FIG. 396 — Eypnpia virgo- yellowish Or pink bands ; in some species the lighter color predominates, so that the fore wings appear to be yellow or pink, spotted (FlG. 395 — Sfilosoma virfinica. 324 THE STUDY OF INSECTS. with black. The hind wings are red, pink, or yellow, and are margined or spotted with black. The thorax is usually marked with three black stripes, of which the lateral ones are borne by the patagia. There is also a black line or a row of black spots along the middle of the back of the ab- domen, and a similar row of spots on each side. Our most common species of this genus is Eyprepia virgo (Fig. 396). The larva of this species feeds on pigweed and other un- cultivated plants. Family LlTHOSHD^E (Lith-o-si'i-dae). The Footman-moths or Lithosiids (Li-tho si-ids). The Lithosiidae include small moths with rather slender bodies, filiform antennae, and usually narrow front wings and broad hind wings. As a rule they are closely scaled insects of sombre colors, a fact that has won for them the title of Footman-moths; but in case of some of the species their livery is very gay. Some species fly by day, while others are attracted to lights at night. This family is closely allied to the Arctiidse ; in fact it is sometimes difficult to tell to which of these families a species belongs. Usually the Footman-moths can be distinguished by the absence of ocelli ; but some species possess very small ones. The palpi are small or moderately developed ; the maxillae are present and quite well developed. The vena- tion of the waigs differs greatly in the different genera ; but in its more important features it resembles that of the Arc- tiidae. The larvae are cylindrical and covered with short, stiff hairs. The majority of the species whose transformations are known feed upon lichens. They transform in very deli- cate cocoons or have naked pupae. Among our more com- mon species are the following: — The Pale Footman, Crambidia pallida (Cram-bid'i-a pal'- li-da. — This moth is of a uniform drab color, with the abdo- men and the inner part of hind wings paler; it expands nine LEPIDOP TERA . 325 tenths of an inch. The moths of the genus Crambidia can be recognized by the fact that veins V, and V, of the fore wings are both wanting, leaving cubitus only two-branched. The Two-colored Footman, Lithosia bicolor (Li-tho'si-a bi'co-lor). — This is larger than the preceding species, expand- ing from one to one and one half inches. It is slate-colored, with the palpi, the prothorax, the costa of the fore wings, and the tip of the abdomen yellow. Vein V, of the fore wings is wanting, leaving cubitus apparently three-branched The Striped Footman, Hypoprepia miniata (Hy-po-pre' pi-a min-i-a'ta). — This beautiful moth is of a deep scarlet color, with three broad lead-colored stripes on the front wings. Two of the stripes extend the entire length of the wings ; while the third is between these and extends from the end of the discal cell to the outer margin (Fig. 397). The outer half of the hind wings is also slate-colored. Vein Va of the fore wings is pres- FlG- 397.-/frA»/«>/« «"«**«• ent ; but vein Va of the hind wings is wanting. The larva feeds upon lichens, and may be found under loose stones or on the trunks of trees. It is dusky, and thinly covered with stiff, sharp, and barbed black bristles, which grow singly from small warts. The cocoon is thin and silky. The Painted Footman, Hypoprepia fucosa (Hy-po-pre'pi-a fu-co'sa). — This species is very similar to the preceding and has been confounded with it. With the Painted Footman the ground-color of the fore wings is partly yellow and partly red. The Clothed-in-white Footman, Clemensia albata (< men'si-a al-ba'ta).— The specific name of this insect is some- what misleading ; for although the general color of the moth is white, there are so many ashen and gray scales, and dark spots, that the general effect is gray. On the front wings the more prominent black spots are six or seven on the costa, one on the discal vein, and a row of small ones on the 326 THE STUDY OF INSECTS. outer margin. The hind wings are white, but finely dusted with gray scales. With this species vein V, is present in both fore and hind wings. The Banded Footman, Cisthene unifascia (Cis-the'ne u-ni-fas'ci-a). — This little beauty (Fig. 398) occurs in the Atlantic States from New York to Texas. The fore wings are lead-colored, and crossed by a FIG 08 —dttkene ye^ow band, which extends also along the inner HHifasda. margin to the base of the wings. The hind wings are pink except the apex, which is lead-colored. There is much variation in the width of the yellow band. Family ZYG^ENID^E (Zy-gaen'i-dae). The Zygcenids (Zy-gce nids). These moths are most easily distinguished from the allied families that are rep- resented in this coun- nil try by the structure of the hind wings. Here we find the tendency of veins II and III to coalesce carried to the great- est extreme, aiey being joined clear to the margin of the wing (Fig. 399) ; oc- casionally forms are found in which the tips of these two veins are separate for a short distance near the apex Of the Wing; FIG. 399— Wings of Ctenucha Virginia. and usually they are separated for a short distance near the base of the wing, as shown in the figure. In some of the more LEPIDOPTERA. $2? specialized forms, as Cosmosoma (Fig. 400), the hind wings are greatly reduced in size, and the branches of radius and cubitus coalesce to a remarkable degree. To the first division of this family belong a small number of bluish-black or brown moths which have more or less vermilion or yellow on the head, prothorax, FlG' v»--c*»*°*»«« •»&• and patagia. These moths are of medium size, expanding from one and one fifth to two inches. The dull color of the wings is usually relieved by the bright color of the head and patagia, and by a layer of blue scales covering the thorax and abdomen ; but in some species these are wanting. The larvae feed on grasses. Some of them strongly resemble those of the Arctiidae in appearance as well as in habits, being thickly clothed with hair ; they also spin cocoons simi- lar to those of Arctiids. Our common forms represent two FIG. 401.— Ctenucha. virginica. FIG. 402 — Scepsis fulvicolht. genera, Ctenucha (Cte-nu'cha) and Scepsis (Scep'sis). In the East we have only a single species of each of these genera, Ctenucha virginica (C. vir-gin'i-ca), which is represented by Figure 401, and Scepsis fulvicollis (S. ful-vi-col'lis), repre- sented by Figure 402. The second division of the family includes a much larger number and a much greater variety of forms. Our most common species is Lycomorpha pholus (Ly-co-mor'pha pho'lus). This is black with the basal half of the fore wings and the basal third of the hind PIG. 403 — L.ycot pholus. >-//;.. 328 THE STUDY OF INSECTS. wings yellow (Fig. 403). A variety of this species occurs in California in which the lighter parts of the wings are pinkish instead of yellow. These moths occur in stony places, where the larvae feed on lichens growing on rocks. In the extreme southern part of our country and in the regions south of that, there occur highly specialized mem- bers of this family, in which the hind wings are greatly re- duced in size, and the veins of the hind wings coalesce to a remarkable degree. In some of these forms the discal por- tion of the wings bears but few if any scales. Cosmosoma auge (Cos-mo-so'ma au'ge) from Florida (Fig. 400) will serve as an example of these. In this species the body and legs are bright red, with the head, end of abdomen, and a dorsal band blue-black ; the veins and borders of the wings are also black. Family THYRIDID.E (Thy-rid'i-dae). The Window-winged Moths. These little moths can be easily recognized by the presence of curious white or yellowish translucent spots upon the wings ; it is these spots that suggests the name Window- winged Moths for the family. In this family the antennae are either strictly filiform or slightly thickened in the middle ; the ocelli are wanting ; the palpi project horizontally, and are somewhat longer than the head ; and the maxillae are strongly developed. The venation of the wings differs from that of all other families of moths, in that all five branches of radius of the fore wings are preserved and arise from the discal cell (Fig. 404).* A similar type of venation is FIG. 404.— Wings of Thy * In a single genus of the Pyromorphids, Triprocris (p. 227, Fig. 268), all the branches of radius arise from the discal cell. LEPIDOPTERA. 329 possessed by the Skippers (Hesperina); but the Window- winged Moths differ from the Skippers in having a well- developed frenulum. The early stages of our species are not known ; but the larva of a European species lives upon the leaves of Cle- matis, which it rolls like a Tortricid. This larva is said to appear like that of a Chrysomelid beetle. It descends to the surface of the ground and makes a dense silken cocoon, more or less mixed with grains of sand. The most common representative of this family in the Eastern and Middle States is the Spotted Thyris, Thyris maculata (Thy'ris mac-u-la'ta). This species (Fig. 405) is brownish black, sprinkled with rust- yellow dots ; the outer margin of the wings, especially of the hind wings, is deeply scal.loped, FIG 4oj _Thyris with the edges of the indentations white. maculata. There is on each wing a translucent white spot ; that of the hind wing is larger, kidney-shaped, and almost divided in two. This species occurs also in the West, as there are specimens from Montana in the Cornell University collection. The Mournful Thyris, Thyris lugnbris (Thy'ris lu-gu'bris), is a larger species found in the Southern States. It can be recognized by Figure 406. It is brownish black, marked with yellow, ns and with the translucent spots yellowish. . w-J -Family SPHINGID^: (Sphin'gi-dae). The Hawk-moths or Sphinxes. Hawk-moths are easily recognized by the form of the body, wings, and antennae. The body is very stout and spin- dle-shaped ; the wings are long, narrow, and very strong ; the antennae are more or less thickened in the middle or towards the tip, which is frequently curved back in the form of a hook ; rarely the antennae are pectinated. The sucking-tube (maxillae) is usually very long, being in some instances twice 330 THE STUDY OF INSECTS. as long as the body ; but in one subfamily it is short and membranous. When not in use it is closely coiled like a watch-spring beneath the head. None of the species have ocelli. The venation of the wings (Fig. 407) is quite character- istic ; the most distinctive feature is the presence of what VII FIG. 407. — Whigs of Phlegethontius celeus. appears to be a cross-vein between subcosta and radius of the hind wing. This apparent cross-vein is due to the fact that veins II and III are grown together for a short distance, and then vein II separates and joins vein I. The obvious presence of vein I in the hind wings is unusual ; but it occurs in the Psychidae, in the Bombycidae, and in the Anthroceridae (a family not represented in our fauna) also. This basal part of vein I is probably preserved in other cases where it appears to be the base of vein II. Thus in Citheronia (Fig. 417) there is a rudiment of the so-called cross-vein, which has entirely disappeared in the more specialized forms of the family to LEPIDOPTERA. 331 which this genus belongs. In the Hawk-moths the frenu- lum is usually well preserved, but in a few it is wanting or rudimentary. In many genera vein III, of the fore wings coalesces with vein III3to its tip, so that vein III is only four-branched. Some of the Hawk-moths are small or of medium size ; but most of them are large. They have the most powerful wings of all Lepidoptera. As a rule they fly in the twilight, and have the habit of remaining poised over a flower while extracting the nectar, holding themselves in this position by a rapid motion of the wings. This attitude and the whir of the vibrating wings gives them a strong resemblance to hum- ming-birds, hence they are sometimes called Humming-bird Moths ; but they are more often called Hawk-moths, on ac- count of their long, narrow wings and strong flight. Of all the beautifully arrayed Lepidoptera some of the Hawk-moths are the most truly elegant. There is a high-bred tailor-made air about their clear-cut wings, their closely fitted scales, and their quiet but exquisite colors. The harmony of the combined hues of olive and tan, ochre and brown, black and yellow, and grays of every conceivable shade, with touches here and there of rose color, is a perpetual joy to the artistic eye. They seldom have vivid colors except touches of yel- low or pink on the abdomen or hind wings, as if their fas- tidious taste allowed petticoats only of brilliant colors always to be worn beneath quiet-toned overdresses. The larvse of the Sphingidae feed upon leaves of various plants and trees, and are often large and quite remarkable in appearance (Fig. 408). The body is cylindrical and naked and usually has a horn behind near the end of the body on the eighth abdominal segment. Sometimes instead of the horn there is a shiny tubercle or knob. We cannot even guess the use of this horn, unless it is ornamental, for it is never provided with a sting. These caterpillars when resting rear the front of the body up in the air, curl the head down in the most majestic manner, and remain thus 332 THE STUDY OF INSECTS. rigid and motionless for hours. When in this attitude they are supposed to resemble the Egyptian Sphinx, and so the typical genus was named Sphinx and the family the Sphingidae. But we think they deserve the name independently of their habits because of the riddle they constantly propound to us as to why they wear this horn on the rear end of the body instead of on the head, where it ought to be in order to be of FIG. 408.— Sphinx ckersis, larva. any use whatever as a horn. These caterpillars are usually of some shade of green and often are ornamented with a series of diagonal stripes along each side. Most species pass the pupa state in the ground in simple cells made in the earth ; some, however, transform on the surface of the ground in imperfect cocoons composed of leaves fastened together with silk. Nearly one hundred species of Hawk-moths occur in this country. The following are some of the more common ones. LEP1DOPTERA. 333 The Modest Sphinx, Marumba modesta (Ma-rum'ba mo-des'ta). — It was, probably, the quiet olive tints in which the moth is chiefly clothed that suggested the name modesta for it, but it is one of the most beautiful of our Hawk-moths. The body and basal third of the fore wings are pale olive ; the outer third of the fore wings is a darker shade of the same color ; while the middle third is still darker (Fig. 409). FlG. 409 — Marumba modest a. The hind wings are dull carmine-red in the middle ; there is a bluish-gray patch with a curved black streak over it near the anal angle. The larva feeds on poplar and cotton- wood. When full grown it is three inches long, of a pale green color, and coarsely granulated, the granules studded with fine white points, giving the skin a frosted appearance. The Twin-spotted Sphinx, Smerinthus geminatus (Sme- rin'thus gem-i-na'- tus). — This exquis- itely colored moth expands about two and one half inches. The thorax is gray with a velvety dark brown spot in the middle. The fore wings are gray, with a faint rosy tint in some specimens, FIG. 4io.-SmeriutAits geminatus. 334 THE STUDY OF INSECTS. and tipped and banded with brown as shown in Figure 410. The hind wings are deep carmine at the middle, and are bordered with pale tan or gray. Near the anal angle there is a large black spot in which there is a pair of blue spots, which suggested the name geminatus. The larva feeds upon the leaves of apple, plum, elm, ash, and willow, Harris's Sphinx, Ellema harrisii (El-le'ma har-ris'i-i). — . This sphinx has interested us chiefly on account of the habits and markings of its larva (Fig. 411). It feeds upon the foliage of pine, and is colored with alternating green and white longitudi- nal strips ; the dorsal stripe is green spotted with red. It has a way of hanging head downward in a pine tas- sel that conceals it entirely from the sight of all but very sharp eyes, its stripes giving a close resemblance to a bunch of pine leaves. The moth ex- pands about two inches ; it is gray with the fore wings marked by several series of small brown spots. The Pen- marked Sphinx, Sphinx chcrsis (Sphinx cher'sis). — This moth is of an almost evenly distributed ashy- gray color. This sombre color is relieved somewhat by a black band on each side of the abdomen, marked with four or five white transverse bars ; by two dark brown, smoky bands which cross the hind wings ; and by a series of black dashes on the fore wings, one in each cell between the apex of the wing and the anal vein. These dashes appear as if drawn casually with a pen. The larva (Fig. 408) is not uncommon upon ash and lilac ; it is greenish or bluish white above, and darker below ; there are seven oblique yellow bands on the sides of the body, each edged FIG. i.- Ellema harrisii, larva. LEPIDOPTERA. 335 above with dark green. When disturbed it assumes the threatening attitude shown in the figure. The Tomato-worm, Phlegethontius celeus (Phleg-e-thon'- ti-us ce'le-us). — This larva is the best known of all our Sphinxes, as it may be found feeding on the leaves of tomato, tobacco, or potato wherever these plants are grown in our country. It resembles in its general appearance the larva of Sphinx chersis (Fig. 408); but its favorite attitude is with the fore end of the body slightly raised. It is usu- ally green, but individuals are often found that are brown, or even black. There appear at frequent intervals in the newspapers accounts of people being injured by a poison excreted by the caudal horn of this larva; but there is absolutely no foundation whatever for such stories. The pupa (Fig. 412) is often ploughed up in gardens, and attracts attention on account of its curious tongue-case, which is free, resembling the handle of a pitcher. The moth is a superb ,. r FIG. 412. — Phlegethontius celtus. creature, expanding four or five inches. It is of many delicate shades of ash-gray, marked with black or very dark gray ; there are a few short black dashes on the fore part of the thorax, and some irregular black spots edged with white on the posterior part; the abdomen is gray with a black middle line, and five yellow, almost square spots along each side. Each of these spots is bordered with black, and has a white spot above and be- low, on the edge of the segment. The hind wings are crossed by four blackish lines, of which the two interme- diate are zigzag. The Tobacco-worm, Phlegethontius Carolina (Phleg-e-thon'- ti-us car-o-li'na).— This species closely resembles the preced- ing, and the two are often mistaken the one for the other. The larvae have similar habits, feeding on the same plants. But the moths are easily distinguished. This species is brown- 336 THE STUDY OF INSECTS. ish gray instead of ashy gray ; at the end of the discal cell of the fore wings there is a distinct white spot ; and the two dark bands crossing the middle of the hind wings are not zigzag, and are less distinctly separate ; often they are united into a single broad band. The Hog-caterpillar of the Vine, Ampelophaga myron (Am-pe-loph'a-ga my'ron). — There is a group of Hawk- moths the larvae of which have the head and first two thoracic segments small, while the two following segments are greatly swollen. These larvae from a fancied resemblance to fat swine have been termed Hog-caterpillars ; and the present species, which is common on grape, has been named the Hog-caterpillar of the Vine. It is a comparatively small species, the full-grown larva being but little more than two inches long. There is a row of seven spots varying in color from red to pale lilac, each set in a patch of pale yellow, along the middle of the back. A white stripe with dark green margins extends along the side from the head F,o. n-Antclopkaga myron, larva with tO the Caudal ^Om, and be- low this are seven oblique stripes. This larva is often infested by Braconid parasites; and it is a common occurrence to find one of them with the cocoons of the parasites attached to it (Fig. 413). The pupa state is passed on the surface of the ground within a rude cocoon made by fastening leaves together with loose silken threads. The adult expands about two and one fourth inches. The fore wings are olive-gray, with a curved, olive-green, oblique band crossing the basal third, a discal point of the same color, and beyond this a large triangular spot with its apex on the costa and its base on the inner margin. The Pandorus Sphinx, Philampclus pandorus (Phi-lam'pe- lus pan-do'rus).— This magnificent moth expands from four to four and one half inches. The ground-color of its wings LEPIDOPTERA, 337 is pale olive, verging in some places into gray ; the markings consist of patches and stripes of dark, rich velvety olive, sometimes almost black (Fig. 414). Near the inner margins of both pairs -of wings the lighter color shades out into pale yellow, which is tinged in places with delicate rose-color. FIG. 414 — Philampelus pandorus. These markings show a harmony of contrasting shades rarely equalled elsewhere by nature or art. The larva is one of the Hog-caterpillars. It feeds upon the leaves of Virginia-creeper. When young it is pinkish in color, and has a long pinkish caudal horn ; as it matures it changes to a reddish brown, and the horn shortens and curls up like a dog's tail and finally disappears, leaving an eye-like tuber- cle. The caterpillar has on each side six cream-colored oval spots, enveloping the spiracles. The White-lined Sphinx, Deilephila lineata (Dei-leph'i-la lin-e-a'ta). — This moth can be easily recognized by Figure 415. Its body and fore wings are olive-brown; there are three parallel white stripes along each side of the thorax ; the outer one of these extends forward over the eyes to the base of the palpi ; on the fore wings there is a buff stripe extending from near the base of the inner margin to the apex, and veins III6 to IX are lined with white; the hind THE STUDY OF INSECTS. 338 wings are black with a central reddish band. The larva is extremely variable in color and markings. It feeds on many plants, among which are apple, grape, plum, and currant. FIG. n\*,.—Deilephila h The Thysbe Clear-wing, Hemaris thysbe (He-ma'ris thys'be). — There is a group of Hawk-moths that have the middle portion of the wings transparent, resembling in this respect the Sesiidae and certain Zygaenids; but they are easily recognized as Hawk- moths by the form of the body, wings, and antennas. One of the more common of these is the Thysbe Clear- wing (Fig. 416). The scaled portions of the wings are of a dark reddish brown ; but this species is most easily distin- guished from our other common species by a line of scales dividing the discal cell lengthwise and representing the po- sition of the base of vein V. The larva of this species feeds on the different species of Viburnum, the snowberry, and hawthorn. The Bumblebee Hawk-moth, Hemaris diffinis (He-ma'ris dif-fi'nis). — This Clear-wing appears to be about as common LEPIDOPTERA. 339 as the preceding, and resembles it somewhat. It lacks, however, the line of scales in the discal cell, and the body is more nearly yellow. This color probably suggested the name Bumblebee Hawk-moth, given to this insect nearly one hundred years ago by Smith and Abbot. The larva feeds on the bush honeysuckle (Diervilld) and the snow- berry (Symphoricarpus). Superfamily SATURNIINA (Sa-tur-ni-i'na). The Saturnians (Sa-tur'ni-ans). The group of families constituting the superfamily Sa- turniina includes the largest of our native moths ; in fact nearly all of our very large moths belong to it ; but it also includes a considerable number of species of moderate size. These moths are most easily distinguished from other moths by the structure of the wings (Fig. 417). Here, as with the Skip- pers and the Butterflies, the frenulum is lost (or nearly so in the low- est family), and its place is taken by a greatly ex- panded humeral angle of the hind wing, which, projecting under the fore wing, insures the acting together of the two in flight without the aid of a frenulum. This losing of the frenulum is also characteristic of the Lasiocampidae. But the Saturnians differ from this family in that vein Vs arises midway between radius and cubitus, or is viu ? _Wings o( cithtronia regalit. 340 THE STUDY OF INSECTS. more closely united to radius than to cubitus, leaVwig the latter apparently three-branched ; while in the Lasiocampidae cubitus appears to be four-branched. This superfamily includes the Bombycidae which are represented in this country only by the Chinese Silkworm and three families of native moths. These can be separated by the following table : — A. Vein Va of the fore wings arising midway between veins Vi and V3. p. 340 BOMBYCID^E. AA. Vein Va of the fore wings arising nearer to vein Vi than to vein V8. B. Hind wings with two anal veins. C. The stalk of veins Vi and V2 of the fore wings separating from radius before the end of the discal cell (Fig. 420, c. v.). p. 342 HEMILEUCID.E. CC. Vein Vi of ih&fore wings separating from radius beyond the apex of the discal cell. D. Veins V, and V2 of the hind wings joined to radius by a dis- tinct Stalk (Fig. 417, C. Z/.). p. 343 CITHERONHD/E. DD. Vein Vi and V2 of the hind wings not stalked (Coloradid). p. 350 SATURNIID^E. BB. Hind wings with only one anal vein. p. 350. . .SATURNIIDJE. Family BOMBYCID.E (Bom-byc'i-dae). The Silk-worm. The Bombycidae as now restricted are not represented in our fauna ; but a single species, the Silk-worm, is frequently bred in this country, and is usually present in collections of Lepidoptera. The Silk-worm, Bombyx mori (Bom'byx mo'ri). — • The moth (Fig. 418) is of a FIG. v&.-Bombyx mori. cream-color with two or three more or less distinct brownish lines across the fore LEPIDOPTERA. 341 wings and sometimes a faint double bar at the end of the discal cell. The head is small ; the antennae are pectinated broadly in both sexes; and the ocelli, palpi, and maxillae are wanting. The abdomen and thorax are densely clothed with woolly hair. The distinctive feature in the venation of the wings (Fig. 419) is the obvious presence of vein I on the hind wings. The usual food of the Silk-worm is the leaf of the mul- berry. Our native species, however, are not suitable. The species that are most used are the white mulberry (Moms alba), of which there are several varieties, and the black mul- berry (Morus ni- >^V -^" /vib grd); the former is the better. The leaves of osage orange (Madura aurantiacd) have also been used as silk-worm food to a considerable ex- tent. In case silk- worms hatch in the springbef ore either mulberry or osage- orange leaves can be obtained, they may be quite sue- M cessfully fed, for a few days, upon lettuce-leaves. The newly-hatched larva is black or dark gray, and i covered with long stiff hairs, which spring from pale-coloi tubercles. The hairs and tubercles are not not.ceable after 342 THE STUDY OF INSECTS. the first molt, and the worm becomes lighter and lighter, until in the last larval period it is of a cream-white color. There is a prominent tubercle on the back of the eighth ab- dominal segment, resembling those borne by certain larvae of the Sphingidae. There are many special treatises on this insect, some of which should be consulted by any one intending to raise silk- worms. Family HEMILEUCID^E (Hem-i-leu'ci-dae). The Hemilencids (Hem-i-leu'cids). This is a small family containing rather large and con- spicuously marked insects. The antennas are broadly pec- tinated in the males and narrowly so or nearly serrate in the females. There is only a iiij+, single pair of teeth to each segment of the antennae. The thorax and abdomen are usually thickly clothed with long woolly hair ; but in some species the cloth- ing of the antennae is less woolly and more scale-like. As to the wings, the frenu- lum is wanting, the humer- al angle of the hind wings being largely developed (Fig. 420); and in both fore and hind wings veins V, and V3 are joined to radius by a common stalk. Our best-known repre- sentative is the Maia-moth, FIG. 4ao.— Wings of H entile Hemileuca maia (Hem-i-leu'ca ma'i-a). In this species (Fig. 421) the wings are thinly scaled, sometimes semi-transparent ; PLATE IV. LEPIDOPTERA. 343 they are black with a common white band near their middle; and the discal veins are usually white and broadly bordered with black. There are great variations in the width of the white band on the wings. The larva feeds on the leaves of oak; it is brownish black, with a lat- FlG. 421. — Hemileuca ttiaia. i 11 • eral yellow stripe ; and is armed on each segment with large branching spines. This species pertains to the eastern part of the continent ; but there are several western species belonging to the genus. In the West there occur also two species of the genus Pseudohazis (Pseu-do-ha'zis). These are P. hero. (P. he'ra), in which the ground-color of the wings is white (Plate IV), and P. eglanterina (P. eg-lan-te-ri'na), in which the ground-color is brown. Both species are spotted and striped with black. In each the abdomen is ringed with black ; there is a large discal spot on each wing, which frequently has a white center due to white scales borne by the discal vein. The base of the wings is dusky. There is a transverse band at the end of the basal third, which is sometimes wanting on the hind wings ; and a broader, wavy, transverse band crossing both wings at the end of the basal two thirds ; and on each wing there is a series of six or seven triangular black spots situ- ated on the ends of the veins, at the outer margin of the wing. It should be said that both in the ground-color and in the markings these two forms vary much ; and it is possi- ble that they are merely varieties of one species. Family ClTHERONHD/E (Cith-e-ro-ni'i-dae). The Royal-moths. The Royal-moths are stout-bodied and hairy, with sunken heads and strong wings. The species are of medium or large 344 THE STUDY OF INSECTS. size, some of them being nearly as large as the largest of our moths. The most obvious character limiting this family is the structure of the antennae of the male. These agree with those of the Saturniidae in having two pairs of teeth to each segment, but differ in being pectinated for only a little more than half their length. These moths also differ from most .Saturniidae in having two anal veins in the hind wings. Al- though the antennae of the male are broadly pectinated, those of the female are filiform. The palpi and maxillae are very small. The thorax and abdomen are densely clothed FIG. 422.-Wings of Cithcronia regali* FIG. 423.— Wings of Anisota ensis. with long hairs. The wings are strong, with prominent veins. The frenulum is wanting, and the humeral angle of the hind wings is very largely developed. In the fore wings vein V, arises from the discal vein (Figs. 422, 423). The larvae are armed with horns or spines, of which those on the second thoracic segment, and sometimes also LEPIDOPTERA. 345 346 THE STUDY OF INSECTS. those on the third, are long and curved. These caterpillars eat the leaves of forest-trees, and go into the ground to trans- form, which they do without making cocoons. The rings of the pupa bear little notched ridges, the teeth of which, to- gether with some strong prickles at the hinder end of the body, assist it in forcing its way upwards out of the earth. This is a small family ; it is not represented in Europe, and less than twenty species are known to occur in this country. The more common ones are the following : — The Regal-moth, CitJieronia regalis (Cith-e-ro'ni-a re-ga'- lis). — This is the largest and most magnificent of the Royal- moths (Fig. 424). The fore wings are olive-colored, spotted with yellow, and with the veins heavily bordered with red scales. The hind wings are orange-red, spotted with yellow, and with a more or less distinctly marked band outside the middle olive. The wings expand from four to six inches. When fully grown the larva measures from four to five inches in length. It is our largest caterpillar, and can be readily recognized by the very long spiny horns with which it is armed. Those of the mesothorax and metathorax are much longer than the others. Of these there are four on each segment ; the intermediate ones measure about three fifths inch in length. This larva feeds on various trees and shrubs. The Imperial-moth, Basilona imperialis (Bas-i-lo'na im- pe-ri-a'lis). — This moth rivals the preceding species in size, expanding from four to five and one half inches. It is sulphur-yellow, banded and speckled with purplish brown. The full-grown larva (Fig. 425) measures from three to four inches in length. It is thinly clothed with long hairs, and bears prominent spiny horns on the second and third thoracic segments. In the early larval stages these thoracic horns are very long and spiny, resembling those of the larva of the Regal-moth. The larva feeds on hickory butternut, and other forest-trees. The Two-colored Royal-moth, Sphingicampa bicolor LEPIDOPTERA. 347 (Sphin-gi-cam'pa bi'co-lor).— In this species the upper side of the fore wings and the under side of the hind wings are yellowish brown, speckled with black. The under side of the fore wings and the upper side of the hind wings are to a con- FIG. 425. — Basilona imperialis, larva. siderable extent pink. There is usually a dark discal spot on the fore wings, upon which, especially in the males, there may be two white dots. This species is more common in the Southern States than in the North. The expanse of wings in the male is two inches ; in the female, two and one half inches. The larva feeds on the leaves of the Honey- locust and of the Kentucky Coffee-tree. Anisota (An-i-so'ta). — To the genus Anisota belong three species of moths that occur in the Eastern United States. These moths are dark yellow, purplish red, or brownish in color, and agree in having the fore wings marked with a white discal dot. The larvae feed on the leaves of oak ; they are more or less striped and are armed with spines. These insects hibernate as pupae. In determining these moths the student should remem- ber that the two sexes of the same species may differ more in appearance than do individuals of different species but of the same sex. The sexes can be distinguished, as already indicated, by the antennae. The three species can be sepa- rated as follows : — 348 THE STUD Y OF INSECTS. The Rosy-striped Oak-worm, Anisota virginiensis (A. vir- gin-i-en'sis). — The wings of the female are purplish red, blended with ochre-yellow ; they are very thinly scaled, and consequently almost transparent ; and are not speckled with small dark spots (Fig. 426). The wings of the male are FlG. 427. — Anisota virg-iniensis, FIG. 426.— Anisota virginiensis, female. male. purplish brown, with a large transparent space on the middle (Fig. 427). The larva is of an obscure gray or greenish color, with dull brownish yellow or rosy stripes, and with its skin rough with small white warts. There is a row of short spines on each segment, and two long spines on the mesothorax. The Orange-striped Oak-worm, Anisota senatoria (A. sen- a-to'ri-a). — The wings of the female are more thickly scaled than in the preceding species and are sprinkled with numer- ous blackish dots ; in other respects the two are quite similar in coloring. The male differs from that of A. virginiensis in lacking the large transparent space on the middle of the wings. The larva is black, with four orange-yellow stripes on the back and two along each side ; its spines are similar to those of the preceding species. The Spiny O^k-worm, Anisota stigma (A. stig'ma). — The female closely resembles that of A. senatoria; and as both species are variable it is sometimes difficult to determine to which a given specimen belongs. In A. stigma the wings are rather darker and have a greater number of blackish spots, and the hind wings are furnished with a middle band which is heavier and more distinct than in A. senatoria. The male differs from that of the other two species in quite closely LEPIDOPTERA. 349 resembling the female in coloring, and in having the wings speckled. The larva differs from the other species of Ani- sota in having long spines on the dorsal aspect of the third thoracic and each abdominal segment in addition to the much longer spines on the mesothorax. It is of a bright tawny or orange color, with a dusky stripe along its back and dusky bands along its sides. The Rosy Dryocampa, Dryocampa rubicunda (Dry-o- cam'pa ru-bi-cun'da). — The wings of this moth (Fig. 428) are pale yellow, banded with rose-color. The dis- tribution of the color varies greatly in different speci- mens. In some the pink of the fore wings predomi- nates, the yellow being re- duced to a broad discal . . FIG. 428.— Dryocampa rubicunda. band, while in one variety the ground-color is yellowish white and the pink is reduced to a shade at the base and a narrow stripe outside the mid- dle. The hind wings may be entirely yellow, or may have a pink band outside the middle. The expanse of wings in the male is one and one half to one and three fourths inches ; in the female, two inches or more. The larva of this species is known as the Green-striped Maple-worm, and is sometimes a serious pest on soft-maple shade-trees. It measures when full grown about one and one half inches. It is pale yellowish green, striped abov< with eight very light, yellowish-green lines, alternating with seven of a darker green, inclining to black. There are two prominent horns on the second thoracic segment, and two rows of spines on each side of the body, one above and one below the spiracles. And on the eighth and ninth abdomi- nal segments there are four prominent dorsal spines, species is one- or two-brooded, and winters in the pupa state. 350 THE STUDY OF INSECTS. Family SATURNIID^: (Sat-ur-ni'i-dae). The Giant Silk-worms. The large size of the members of the Saturniidae, arid the ease with which the cocoons of most of the species can be collected, render them well known to every beginner in the study of entomology. The family includes our largest lepi- dopterous insects ; and all of the species known to us are above medium size. They are stout-bodied, hairy moths, with more or less sunken heads, and strong, wide wings. They may be distinguished from the Citheroniidae, some of which rival them in size, by the form of the antennae of the males, and by the fact that except in the lowest genus, Coloradia, which is a rare insect from the far West, the hind wings are furnished with only one inner vein. The adults fly at night, and are attracted by lights. The head is small and deeply sunken in the thorax ; the antennae are either fili- form or pectinated in the females, but always pecti- nated in the males ; and the pectinations extend to the tip. Where the antennae of both sexes are pectinated, the males can be distin- guished by the larger size of their antennae. The palpi are small, and the maxillae p.. w. but little developed, often rio. 429.— Wings of Samia cecropia. obsolete. The thorax is densely clothed with hair. The wings are broad, and are often furnished with transparent, window- like spots. The frenulum is wanting. The humeral angle LEPIDOPTERA. 351 of the hind wing is largely developed, and is usually strength- ened by a deep furrow, the bottom of which is sometimes thickened so as to appear like a humeral vein (Fig. 429). The larvae live exposed on the leaves of trees and shrubs ; they are more or less armed with tubercles and spines, and are very conspicuous on account of their large size. They transform within silken cocoons, which are usually very dense, and in some cases have been utilized by man. These cocoons are often attached to trees and shrubs, and are sometimes inclosed in a leaf. They can be easily collected during the winter months, and the adults bred from them. The following species are those that the young student is most likely to find : — The lo-moth, Automeris io (Au-tom'e-ris i'o). — This is the most common of the smaller species of the family. The female is represented by Figure 430. In this sex the i 430^ — A utomeris io. ground-color of the fore wings is purplish red. The male differs greatly in appearance from the female, being some- what smaller and of a deep yellow color, but it can be easily recognized by its general resemblance to the female in other respects. The larva is one that the student should learn to recog- nize in order that he may avoid handling it ; for it is armed 352 THE STUDY OF INSECTS. with spines the prick of which is venomous (Fig. 431). It is green, with a broad brown or reddish stripe, edged below with white, on each side of the abdo- men. The spines are The Polyphemus-moth, Telea polyphemus (Te'le-a pol-y- phe'mus). — This is a yellowish or brownish moth with a window-like spot in each wing. There is a gray band on the costal margin of the fore wings ; and near the outer mar- gin of both pairs of wings there is a dusky band, edged FIG. 432.— Telea polyphe, . without with pink ; the fore wings are crossed by a broken sky or reddish line near the base, edged within with white :>r pink. The transparent spot on each wing is divided by discal vein, and encircled by yellow and black rings. PLATE V. LEPIDOPTERA. 353 On the hind wings the black surrounding the transparent spot is much widened, especially toward the base of the wing, and is sprinkled with blue scales. The wings expand from five to six inches. The larva (Fig. 432) feeds on oak, butternut, basswood, elm, maple, apple, plum, and other trees. When full grown it measures three inches or more in length. It is of a light green color with an oblique yellow line on each side of each abdominal segment except the first and last ; the last segment is bordered by a purplish-brown V-shaped mark. The tubercles on the body are small, of an orange color with me- tallic reflections. The co- coon (Fig. 433) is dense and usually enclosed in a leaf ; it can be utilized for the manufacture of silk. When the adult is ready to emerge, it excretes a fluid which softens the cocoon at one end, and FlG" 433.-™ breaking the threads it makes its exit through a large round hole. The Luna Moth, Tropaa luna (Tro-pae'a lu'na). — This magnificent moth is a great favorite with amateur collectors (Plate V). Its wings are of a delicate light green color, with a purple-brown band on the costaof the fore wings; there is an eye-like spot with a transparent center on the discal vein of each wing; and the anal angle of the hind wings is greatly prolonged. The larva feeds on the leaves of wal- nut, hickory, and other forest-trees. It measures when full grown about three inches in length. It is pale bluish green with a pearl-colored head. It has a pale yellow stripe along each side of the body, and a transverse yellow line on the back between each two abdominal segments. The cocoon resembles that of the preceding species in form, but is very thin, containing but little silk. 354 THE STUDY OF INSECTS. The Promethea Moth, Callosamiapromcthea(Ca\-\o-s2i'rc\\-di pro-me'the-a).— This is the most common of the Giant Silk- worms. The wings of the female (Fig. 434) are light reddish j. \T>\.—Callosa.mia fromethea, female. brown ; the transverse line crossing the middle of the wings is whitish, bordered within with black ; the outer margin of the wings is clay-colored, and each wing bears an angular discal spot. The discal spots vary in size and distinctness in different specimens. The male differs so greatly from the female that it is liable to be mistaken for a distinct species. It is black- ish, with the transverse lines very faint, and with the discal spots wanting or very faintly indicated. The fore wings also differ markedly in shape from those of the female, the apex being much more distinctly sickle-shaped. The larva when full grown' measures two inches or more in length. It is of a clear and pale bluish-green color ; the legs and anal shield are yellowish ; and the body is armed with longitudinal rows of tubercles. The tubercles are black, polished, wart-like elevations, excepting two each on the second and third thoracic segments, which are larger and rich coral-red, and one similar in size to these but of a yellow color on the eighth abdominal segment. This larva feeds on the leaves LEPIDOPTERA. 355 of a large proportion of our common fruit and forest trees ; but we have found it more frequently on wild cherry and ash than on others. The cocoons can be easily collected during the winter from these trees. This is the best way to obtain fresh specimens of the moths, which will emerge from the cocoons in the spring or early summer. The cocoon (Fig. 435) is interesting in structure. It is greatly elongated and is enclosed in a leaf, the petiole of which is securely fast- ened to the branch by a band of silk extending from the co- coon ; thus the leaf and enclosed cocoon hang upon the tree throughout the winter. At the upper end of the cocoon there is a conical valve like arrange- ment which allows the adult to emerge without the necessity of making a hole through the cocoon. This structure is char- acteristic of the cocoons of the moths of this and the following genus. The Angulifera Moth, Callo- samia angulifera (C. an-gu-lif'e- ra). — This is a somewhat rare in- sect which so closely resembles the Promethea Moth that by many it is considered a variety of it. Specimens of it are usu- ally a little larger than those of C. promethea, and the transverse line and discal spots are more angular. The most important FlG^_Ca^amia/rfme(Jkf<,>cocooa. differences, however, are pre- sented by the male, which quite closely resembles the female 356 THE STUDY OF INSECTS. of the Promethea Moth in color and markings, and thus differs decidedly from the male of that species. The Cecropia Moth, Samia cecropia (Sa'mi-a ce-cro'pi-a).— This is the largest of our Giant Silk-worms, the wings of the adult expanding from five to six and one half inches. The ground color of the wings is a grizzled dusky brown, espe- cially on the central area. The wings are crossed beyond the middle by a white band, which is broadly margined without with red. and there is a red spot near the apex of the fore wing just outside of a zigzag line. Each wing bears near its center a crescent-shaped white spot bordered with red. The outer margin of the wings is clay-colored. The larva is known to feed on at least fifty species of plants, including apple, plum, and the more common forest trees. When full grown it measures from three to four inches in length and is dull bluish green in color. The body is armed with six rows of tubercles, extending nearly its entire length, and there is an additional short row on each side on the ventral aspect of the first five segments follow- ing the head. The tubercles on the second and third thoracic segments are larger than the others, and are coral-red. The other dorsal tubercles are yellow, excepting those of the first thoracic and last abdominal segments, which with the lateral tubercles are blue ; all are armed with black bristles. The FIG. 436.— Sa FIG. 437. — Samia c LEPIDOPTERA. 357 pupa is represented by Figure 436 and the cocoon by Figure 437- The Cecropia-moth occurs from the Atlantic coast to the Rocky Mountains. In the far West its place is taken by very closely allied forms, which are supposed to be distinct. In these the ground-color of the wings is usually a reddish or dusky brown. The form occurring in Utah and Arizona is Samia gloveri (S. glov'er-i) ; that found on the Pacific coast is Samia californica. The Ailanthus-worm, Philosamia cynthia (Phil-o-sa'mi-a cyn'thi-a), is an Asiatic species that has been introduced into this country. It has become a pest in the vicinity of New York, where it infests the Ailanthus shade-trees. The moth differs from all our native species of this family in having rows of tufts of white hairs on the abdomen. The cocoon resembles that of the Promethea-moth. Family LACOSOMID^E (Lac-o-som'i-dae). The Sack-bearing Frenulum-losers. This family so far as is now known includes only two species that are found in the United States, and both of these are rare ; farther south several other species occur. They are our only native Frenulum-losers that retain a rudi- ment of thefrenulum, but, as in the silk-worm, this frenulum is very small and the humeral angle is greatly expanded, so it is probable that the frenulum is of but little if any use (Fig. 438). It was the presence of this rudiment that first suggested to the writer that those families of the Lepidop- tera that we have termed Frenulum-losers were descended from frenulum-bearing ancestors. The Lacosomidse seem to be the sole survivors of a very distinct line of descent. In many respects they appear to be closely allied to the Saturniina, especially to the Bom- bycidae. But they differ markedly both in the structure and in the habits of the larvae ; and, too, the wings of the adult, 358 THE STUDY OF INSECTS, although at first sight resembling those of the silk-worm, are really quite different. In the coalescence of the branches of ra- dius of the fore wings veins III, and III4 remain separate, while in the Satur- niina these are the first branches to coa- lesce. And in the hind wings there is no indication that vein I becomes joined to the base of vein II as is shown to be the case in the most generalized S a t u r - niina (Figs. 417 and 419). The members of FIG. 438.-Wing8of cidnnus mehheimeriL this family in the lar- val state feed upon leaves, and protect themselves by mak- ing a case of leaves within which they live (Fig. 439). FIG. 439.— Case of larva of FIG. 440. — Cicinnus inelsheimerii Melsheimer's Sack-bearer, Cicinnus melsheimerii (Ci-cin'- nus mels-hei-me'ri-i). — The larva of this species feeds on oak. The adult moth (Fig. 440) is of a reddish gray color, finely sprinkled all over with minute black dots ; there is a small black spot at the end of the discal cell of the fore wings ; LEPIDOPTERA. 359 and both pairs of wings are crossed by a narrow blackish band. This species is quite widely distributed ; but is quite rare in most places. The other representative of this family found in the United States is Lacosoma chiridota (Lac-o-so'ma chir-i-do'- ta). This species is even more rare than the preceding; it is somewhat smaller, and dark yellowish brown in color ; but its general appearance is very similar. The venation of the wings is also similar to that of Cicinnus except that vein VIII of the hind wing is wanting. Family LASIOCAMPID^E (Las-i-o-cam'pi-dae). The Lasiocampids (Las-i-o-cam pids). This family includes the Tent-caterpillars and the Lap- pet-caterpillars. The adults are stout-bodied, hairy moths of medium size. The antennae are pectinated in both sexes, and are from one fourth to one half as long as the front wings; the teeth of the an- tennae of the male are usu- ally much longer than those of the female. The ocelli a wanting ; and the palpi are usually short and woolly. But the most distinctive char- acteristic is found in the wings. The frenulum is want- ing, there being instead, as in the Saturniina, a largely- expanded humeral angle of the hind wings. But these moths differ from the Satur- niina in having cubitus ap- "=• 44.-w.-n of c/**™/. *.* parently four-branched and in having the humeral angle 360 THE STUDY OF INSECTS. strengthened by the development of some extra veins, the humeral veins (Fig. 441, //. v.\* The larvae of the Lasiocampids feed upon the foliage of trees, and are frequently very destructive. The family is a small one, less than thirty North Ameri- can species being known to entomologists. Our more com- mon ones represent three genera : Clisiocampa (Clis-i-o-cam'- pa), which includes the Tent-caterpillars, and PJiyllodesma (Phyl-lo-des'ma) and Tolype (Tol'y-pe), which include the Lappet-caterpillars. There are several species of Tent-caterpillars in this country. Most of them belong to the Pacific coast; but two are common in the East. Of these the most com- mon one is the Apple-tree Tent -caterpillar, Clisiocampa americana (C. a-mer-i-ca'na). This is the insect that builds large webs in apple and wild cherry trees in early spring. Figure 442 represents its transformations. The moth is dull yellowish brown or reddish brown, with two transverse whitish or pale yellowish lines on the fore wings. The figure represents a male ; the female is somewhat larger. These moths appear early in the summer. The eggs are soon laid, each female laying all her eggs in a single ring-like cluster about a twig; and here they remain unhatched for about nine months. This cluster is covered with a substance which protects it during the winter. The eggs hatch in early spring, at the time or just before the leaves appear. The larvae that hatch early feed upon the unopened buds till the leaves expand. The larvae are social, the entire brood that hatch from a cluster of eggs keeping together and building a tent in which they live when not feeding. The figure represents a specimen in our collection. In this case the tent was begun near the cluster of eggs. But usu- *So far as we know, humeral veins occur nowhere else in the Lepidoptera, although in many butterflies vein I of the hind wings is preserved and appears like a humeral vein. The humeral veins of the Lasiocampida do not represent any of the primitive veins, but are developed secondarily. LEPIDOPTERA, 361 ally the larvae soon after hatching migrate down the branch towards the trunk of the tree until a fork of considerable size is reached before they begin their tent. This is neces sary, as the completed tent often measures two feet or more m length. The larvae leave the nest daily in order to feed • and spin a silken thread wherever they go. The larvae be' FIG. 442. — Clisiocatnpa antericana, eggs, tent, larva, cocoons, and adult. come full grown early in June ; one of them is represented on a partially-eaten leaf in the figure. When ready to transform they leave the trees and make their cocoons in some sheltered place. These cocoons are quite peculiar in appearance, having a yellowish white powder mixed with the silk. The pupa state lasts about three weeks. The easiest way to fight this pest is to destroy the webs containing the larvae as soon as they appear in the spring. This should be done early in the morning, or late in the 362 THE STUDY OF INSECTS. afternoon, or on a cold day, when the larvae are not scat- tered over the tree feeding. The other Eastern species of this genus is the Tent-cater- pillar of the Forest, Clisiocampa disstria (C. dis'stri-a). This species resembles the preceding in habits. It is more apt, however, to feed upon forest-trees. The moth differs from C. americana in having the oblique lines on the wings dark instead of light; the larva differs in having a row of spots along the back instead of a continuous narrow line ; and the egg-masses differ in ending squarely instead of being rounded at each end. The more common species of the Pacific coast are Clisio- campa californica, whose nests may be found on oaks in March and April, and Clisiocampa constricta, which infests fruit-trees later in the season. The caterpillars of the last- named species do not make a tent, although they live in colonies. The larvae of Tolype and Phyllodesma are remarkable for having on each side of each segment a little lappet or flat lobe ; from these many long hairs are given out, forming a fringe to the body. When at rest the body of the larva is flattened, and the fringes on the sides are closely applied to the surface of the limb on which the insect is. Thus all ap- pearance of an abrupt elevation is obliterated ; the colors of these larvae are also protective, resembling those of the bark. The genus Tolype includes only two common North ^^^ v . .^fift -American species ; both of these f$bb^jj££^^KKj/ occur in the East. The more com- V^s- JR? mon of the two is the Velleda B& Lappet, Tolype -velleda (Tol'y-pe ^^ I 1^^^ vel'le-da). The body of the moth PP is milk-white, with a large black- „„ ish spot on the middle of its back FIG. 443-— retype velleda. . r (Fig. 443). That part of this spot which is on the thorax is composed of erect scales ; the cau- LEPIDOPTERA. 363 dal part, of recumbent hairs. The wings are dusky gray, crossed by white lines as shown in the figure. The figure represents the male ; the female is much larger. The moths are found in August and September. The larva feeds upon the leaves of apple, poplar, and syringa. Its body is bluish gray, with many faint longitudinal lines ; and across the back of the last thoracic segment there is a narrow velvety-black band. The larva reaches maturity during July. The cocoon is brownish gray, and is usually attached to one of the branches of the tree on which the larva has fed. The second species of this genus is known as the Larch Lappet, Tolype laricis (T. lar'i-cis). This is a smaller species, the females being about the size of the male of the preced- ing species, and the males expanding only about one and one fourth inches. The wings of the females are marked much like those of T. velleda, except that the basal two thirds of the front wings are much lighter, and the dark band on the outer third is narrower and much darker than the other dark bands. The males are bluish black, with the markings indistinct. The larva feeds upon the larch. When mature it is of a dull brown color and less than one and one half inches in length. When extended the front of the first thoracic segment is pale green, and the incision between the second and third is shining black. The larva matures during July. The cocoon is ash-gray, flattened and moulded to the limb to which it is attached, and partially surround- ing it. The moths appear in August or September. The winter is passed in the egg state. The genus Phyllodesma includes three Califcrnian and two Eastern species. The more common one of the latter is the American Lappet, P. americana (Fig. 444). The moth is reddish brown, with the inner angle FIG. of the front wings and the costal margin of the hind wings deeply notched. Beyond the mid- 364 THE STUDY OF INSECTS. die of each wing there is a pale band edged with zigzag, dark brown lines. The larva lives upon apple, cherry, oak, birch, maple, and ash. When full grown it measures two and one half inches in length and one half inch in breadth. The upper side is slate-gray, mottled with black, with two transverse scarlet bands, one on the second and one on the third thoracic segments. There is a black spot at each end and in the middle of each of these bands. The larva is found during July and August. It is said that the cocoons are attached to limbs like those of Tolype ; but the larvae of this species which we have bred made their cocoons between leaves, or in the folds of the muslin bag enclosing the limb upon which they were feeding. The species passes the winter in the pupa state ; and the moth appears in y ' June, when it lays its eggs upon the leaves of the trees it infests. Superfamily HESPERIINA (Hes-per-i-i'na). The Skippers. The Skippers are so called on account of their peculiar mode of flight. They fly in the daytime and dart suddenly from place to place. When at rest most species hold the wings erect in a vertical position like butterflies; in some the fore wings are thus held while the hind wings are extend- few extend both pairs of wings horizontally. The antennae LEPIDOPTERA. 365 are thread-like, and enlarged toward the tip; but in most cases the extreme tip is pointed and recurved, forming a hook. The abdomen is usually stout, resembling that of a moth rather than that of a butterfly. The skippers are most easily distinguished by the peculiar venation of the fore wings, vein III being five-branched, and all the branches arising from the discal cell (Fig. 445). In some butterflies all the branches of vein III appear to arise from the discal cell ; but this is because two of the branches coalesce to the margin of the wing. In such butterflies vein III appears to be only four-branched. This superfamily includes two families — the Giant Skip- pers, Megathymida, and the Common Skippers, Hesperiidce. These can be distinguished as follows: — A. Head of moderate size ; club of antenna large, neither drawn out at the tip nor recurved. Large skippers, with wing expanse of two inches or more. p. 365 MEGATHYMID^E. AA. Head very large ; club of antenna usually drawn out at the tip, and with a distinct recurved apical crook. In a few forms the crook of the antennae is wanting; such forms can be distin- guished from the Megathymidae by their smaller size, the wing expanse being less than one and one fourth inches, p. 368. HESPERIID^G. Family MEGATHYMID^: (Meg-a-thym'i-dae). The Giant Skippers. This family includes a small number of large skippers, which are found in the South and far West. In the adult insect the head is of moderate size, the width, includ- ing the eyes, being much less than that of the metathorax. The club of the antennae is large ; and, although the tip is turned slightly to one side, it is neither drawn out to a point nor recurved. The body is very robust, even more so than in the Hesperiidae. These insects fly in the day- time and with a rapid, darting flight. When at rest they fold their wings in a vertical position. In the more general features of their venation the wings 366 THE STUDY OF INSECTS. closely resemble those of the Hesperiidae. But the Giant Skippers exhibit a very peculiar specialization of wing struc- ture in the male sex. Here the two branches of vein VII of the fore wings separate from each other and from the cross- vein connecting them with vein V,, near the base of the wing (Fig. 446). In this sex this cross-vein, the branches of FIG. 447.— Wings of Megathymus * co/agui, female. FIG. 446 —Wings of Megatkymus yucca, male. vein VII, and vein IX are all very stout. The strengthening of these veins is evidently a specialization that increases the power of flight of this sex. For these stout veins must aid in depressing the hind wings during the downward stroke of the wings, as the hind wing is overlapped by that part of the fore wing traversed by these veins. The separation of the branches of vein VII from each other and from the cross- vein, so near the base of the wing, is directly correlated with the strengthening of these veins. In the course of the perfecting of the powers of flight in the male these LEPIDOPTERA. 367 veins have split apart, so that they overlie the hind wings to a greater extent than they do in the female (Fig. 447), which probably represents a more primitive condition. It is a common occurrence for the wings of the male to be more highly specialized than those of the female, for, in the seeking of mates, the males fly more than do the females. But it is unusual for veins to coalesce to a smaller extent in specialized forms than in those more generalized. In other words, the ordinary course of specialization is for FlG> **>-*'#"**""« •«<- the costal margin, which forms a long slit-like pocket, cor usually have a long w 370 THE STUDY OF INSECTS. taining a sort of silky down. This is supposed to be a scent-organ. When this pocket is tightly closed it is diffi- cult to see it. Nearly seventy species belonging to this subfamily have been found in America north of Mexico. The following are some of the more common of these : — The Silver-spotted Skipper, Epargyreus tityrus ( Ep-ar- gy're-us tit'y-rus). — This skipper is represented on our colored plate (Plate I, Fig. 4). It is dark chocolate-brown, with a row of yellowish spots extending across the fore wing and with a large silvery-white spot on the lower side of the hind wing. It is found in nearly the whole United States, from Massachusetts to California, except in the extreme Northeast and Northwest. The larva (Fig. 450) feeds upon various 'papilionaceous plants. We have found it common on locust. It makes a nest, within which it re- mains concealed, by fastening together, with silk, the leaf- lets of a compound leaf (Fig. 452). FlG. 452.— Nest of larva of Epargyreus tityrus. The Long-tailed Skipper, Etidamus proteus (Eu'da-mus pro'te-us).— This Skipper by the shape of its wings reminds one of a swallow-tail butterfly, the hind wings being furnished with long tails. It expands about one and three fourths inches; and the greatest length of the hind wings is about one and one fourth inches. The wings are very dark choc- olate-brown ; the front wings contain several silvery-white spots ; and the body and base of the wings bear metallic- LEPIDOPTERA. 371 green hairs. The larvae feed upon both Leguminosae and Cruciferae. In the South it is sometimes a pest in gardens, cutting and rolling the leaves of beans, turnips, and cabbage, and feeding within the rolls thus formed. It is found on the Atlantic border from New York southward into Mexico. There are two common skippers which are nearly as large as the two described above, but which have neither the yellow band of the first nor the long tails of the second ; neither do they have the brown spots characteristic of the following genus. These two skippers belong to the genus Thorybes. The wings are of an even dark brown ; the fore wings are flecked with small or very small irregular white spots, and the hind wings are crossed beneath by two rather narrow, parallel, inconspicuous darker bands. These skippers are distinguished as follows : — The Northern Cloudy-wing, Thorybes pylades (Thor'y-bes pyl'a-des). — In this species the white spots on the fore wing are usually mere points, although their number and size vary. The species is found in nearly all parts of the United States. The larva commonly feeds on clover. The Southern Cloudy-wing, Thorybes bathyllus (T. ba-thyl'lus).— In this species the white spots are larger than in the preceding, almost forming a continuous band. This skipper is widely distributed over the eastern United States, except the more northern portions. To the genus Thanaos belong a large number of species which on account of their dark colors have been named Dusky-wings. These species resemble each other so closely in markings that it is very difficult to separate them with- out longer descriptions than we can give here. The one following will serve as an example. Martial's Dusky-wing, Thanaos martialis (Than'a-os mar-ti-a'lis). — The wings are grayish brown with FIG. 453.- T*« **« ***&•*. many dark brown spots evenly distributed and with several 372 THE STUDY OF INSECTS. minute white ones on the outer half of the fore wings (Fig. 453). This skipper is found throughout the greater part of the United States east of the Rocky Mountains. Among the smaller members of this subfamily are the skippers of the genus Pliolisora. The most widely dis- tributed species of this genus is the Sooty-wing, Pholisora catnllus (Phol-i-so'ra ca-tul'lus). The expanse of the wings is a little more than one inch. The wings are nearly black, marked with minute white spots, which vary in size and number. This species is found throughout the United States except along the extreme northern border. The genus Hesperia includes a considerable number of small skippers, which are easily recognized by their check- ered markings of white upon a dark brown ground. Small white spots on the wings are common in this subfamily, but in this genus the white spots are unusually large, so large in some cases that they occupy the greater part of the wing. One of the more common species is the Variegated Tessellate, Hesperia montivaga (Hes-pe'ri-a mon-tiv'a-ga). This is distributed from the Atlantic to the Pacific, and is the only one common in the Eastern United States. In this species more than one half of the outer two thirds of both fore and hind wings is white. Subfamily PAMPHILIN.E (Pam-phi-li'nse). Skippers with a Discal Patch. This subfamily includes the greater number of our smaller skippers. Some of the species, however, surpass in ^^ -v r ^^ size many of the Hesperiinae. To the BJ^^W^^HB Pamphilinae belong all of our common ^f tawny skippers, as well as some black ^R or dark brown species. The antennae ^^F w ^^r usually have a stout club, with a short, FIG. w.-Limocho,es pon recurve(^ t{P ' sometimes this tip is Mac, male. wanting. In the majority of our species the males can be recognized at a glance by a conspicuous LEPIDOPTERA. 373 discal patch, which usually appears to the naked eye like a scorched, oblique streak near the center of each fore wing (Fig. 454). This patch is a complicated organ, com- posed of tubular scales that are outlets of scent-glands and other scales of various shapes. The females can be recognized by their resemblance in other respects to the males. In some species the discal patch is wanting in the males also. This subfamily is an exceedingly difficult one to study. More than one hundred species have been described from America north of Mexico ; and in many cases the differences between allied species are not well marked. The following two are named merely as examples, The first is easily recognized. But it is not worth while for the beginning student to attempt to distinguish other members of this subfamily. The Least Skipper, Ancyloxipha numitor (An-cy-lox'i-pha nu'mi-tor). — This skipper is the smallest of our common species, and is also remarkable for lacking the recurved hook at the tip of the antennae. The wings are tawny, broadly margined with dark brown. In some specimens the fore wings are almost entirely brown. The larger in- dividuals expand about one inch. The larva feeds upon grass in damp places. The Black Dash, Limochores pontiac (Li-moch'o-res pon'ti-ac).— The male of this species is represented by Figure 454. It is blackish brown, with considerable yellow on the basal half of the fore wings. The discal patch is velvety black. This species is distributed from Massachu- setts to Nebraska. Superfamily PAPILIONINA (Pa-pil-i-o-ni'na). The Butterflies. The butterflies differ from moths in that they have clubbed antennae., fly only in the daytime, and hold the 374 THE STUDY OF INSECTS. wings erect above the back when at rest. There are some moths that have clubbed antennae,and others that fly by day but no moth presents all three of the charac- teristics given above. It is more difficult to distinguish the but- terflies from the skip- pers ; yet this can be easily done. In but- terflies the club of the antenna is bluntly rounded at the tip instead of being fur- nished with a re- curved point as in most skippers ; the abdomen is very slen- der ; and some of the branches of radius of the fore wings co- alesce beyond the There are butterflies in vn. VII FIG. 455.— Wings of Basilarchia astyanax. apex of the discal cell (Fig. 455). which all of the branches of radius present arise from the discal cell ; but this is due to the fact that two of the branches coalesce to the edge of the wing, as is shown by the fact that in these butterflies radius has less than five branches. This superfamily includes four families, which can be separated as follows : — A. Cubitus of the fore wings apparently four-branched (Fig. 456). P- 375 PAPILIONIDJE. A A. Cubitus of the fore wings apparently three-branched (Fig. 455). B. With six well-developed legs, although in some species the fore LEPIDOPTEKA. 375 legs of the male are a little shorter, and the tarsi of these lack one or both claws ; radius of the fore wings, with rare exceptions, only three- or four-branched. To determine the number of branches of radius, count the two cubital and the three medial branches first ; the branches left between veins Vi and II belong to radius. C. Vein V, of the fore wings arising at or near the apex of the ' discal cell (Fig. 465) except in Feniseca tarquinius, in which the wings are dark brown, with a large fulvous spot on each. p. 388 LYCJENID^. CC. The first branch of media of the fore wings united with the last branch of radius for a considerable distance beyond the apex of the discal cell (Fig. 460). Ground color of wings white, yellow, or orange, p. 381 PIERID^E. BB. With only four well-developed legs, the fore legs being un- used, much shorter than the others, and folded on the breast like a tippet (except in the female of Hypatus). Radius of fore wings five-branched (Fig. 467), p. 395 NYMPHALIDA:. Family PAPILIONID^: (Pa-pil-i-on'i-dae). The Swallow-tails and the Parnassians. This family includes the swallow-tail butterflies, which are common throughout our country, and the Parnassians, which are found only on high mountains or far north. These insects are distinguished from all other butterflies by the fact that vein V, of the fore wings appears to be a branch of cubitus, making this vein appear four-branched (Fig. 456), and also by the fact that the anal area of the hind wings is more reduced than the anal area of the fore wings, the former containing only a single anal vein, the latter two or three. The caterpillars are never furnished with spines, but are either naked or clothed with a few fine hairs. In a single species in our fauna (Laertias philenor) the body of the larva bears fleshy filaments. A striking peculiarity of the larvae of this family is the presence of a pair of bright-colored fleshy " horns," which can be projected from a slit in the dorsal wall of the pro- 376 THE STUDY OF INSECTS. thorax. These have been termed osmateria (os-ma-te'ria), and are supposed to be organs of defence ; for they exhale when pushed mj out an odor which in some species is exceedingly dis- agreeable. The chrysalids are thickened in the middle and taper considerably at each end ; they are more or less angulated, and have certain parts excessively produced ; they are sus- pended by the tail and by a loose girth around the middle. This family includes two well-marked subfami- lies, which are distin- guished as follows : — . Hind wings with a tail- like prolongation ; ground- color of wings black ; radius of fore wings five-branched ; the base of vein VIII of fore wings preserved as a spur-like branch of vein VII (Fig. 456). p. 376 PA PI LI ON I N^E. AA. Hind wings without tail-like prolongation ; ground color of wings white; radius of fore wings four-branched ; vein VIII of fore wings wanting, p. 380 PARNASSIIN^E Subfamily PAPILIONIN^E (Pa-pil-i-o-ni'nse). The Swallow-tails. These magnificent butterflies are easily recognized by their large size and the tail-like prolongations of the hind wings. The ground color of the wings is black, which is FIG. 456.— Wings cf Papilla polyxenes. LEPIDOPTERA. 377 usually marked with yellow, and often with metallic blue or green. There are about twenty-five species of swallow-tails in America north of Mexico. The following well-known spe- cies will serve as illustrations. The Black Swallow-tail, Papilio polyxenes (Pa-pil'i-o po- lyx'e-nes). — The larva of this swallow-tail (Fig. 457) is well known to most country children. It is the green worm, ringed with black and spotted with yellow, that eats the leaves of caraway in the back yards of coun- try houses. It feeds also on parsnip and other umbelliferous plants. These caterpillars always fascinated us in our childhood ; we have spent many idle moments in poking them with straws to see them rear upward and project their yellow horns, which gave off a sickening odor. When ready to transform the caterpillar crawls away to a fence or the side of the house and changes to an angular pupa, sus- pended by the tail and by a little silken girth around the middle. In the adult the wings are black, crossed with two rows of yellow spots, and with marginal lunules of the same color. The two rows of spots are much more'distinct in the male than in the female the in- ner row on the hind wing forming a continuous band crossed FIG. 457.— Papilio folyxenes, larva. 378 THE STUDY OF INSECTS. with black lines on the veins. Between the two rows of spots on the hind wings there are many blue scales ; these are more abundant in the female. Near the anal angle of the hind wing there is an orange spot with a black center. On the lower surface of the wings the yellow markings become mostly orange and are heavier. This species is found throughout the United States and in the southern parts of Canada. The Tiger Swallow-tail, Jasoniades g/aucus(JaiS-o-m'a.-des glau'cus). — The larva of this butterfly (Fig. 458) is even more striking in appearance than that of the preceding species. When full grown it is dark green, and bears on each side of the third thoracic segment a large greenish- yellow spot, edged with black, and enclos- ing a small purple spot bordered with black. This caterpillar has the curious habit of weaving upon a leaf a carpet of silk, upon which it rests when not feed- ing ; when nearly full grown, instead of spinning a simple carpet as before, it stretches a web across the hollow of a leaf and thus makes a spring bed upon which it sleeps (Fig. 458). In the adult state two distinct forms of this insect occur. These differ so greatly in appearance that they were long con- sidered distinct species. They may be FIG. ta.-Jwniadesglau- ..... va upon its bed. distinguished aS follows : (i) The Turnus ¥orm,Jasoniades glaucus turnus. — The wings are bright straw-yellow above, and pale, faded straw- yellow beneath, with a very broad black outer margin, in which there is a row of yellow spots. On the fore wings there are four black bars, extending back from the costa ; the inner one of these crosses the hind wings also. This form LEPIDOPTERA. 379 is represented by both sexes, and is found in nearly all parts of the United States and Canada. (2) The Glaucus Form, Jasoniades glaucus glaucus. — In this form the disk of the wings is entirely black, but the black bands of the Turnus form are faintly indicated, espe- cially on the lower surface, by a darker shade. The mar- ginal row of yellow spots is present, and also the orange spots and blue scales of the hind wings. This form is rep- resented only by the female sex, and occurs only in the more southern part of the range of the species, i.e., from Delaware to Montana and southward. The Zebra Swallow-tail, Iphiclidcs ajax (Iph-i-cli'des a'jax).— This butterfly (Fig. 459) differs from all other swal- low-tails found in the eastern half of the United States in hav- ing the wings crossed by several bands of greenish white. This is one of the most in- teresting of our but- terflies, as it occurs under three distinct forms, two of which were considered for a long time distinct species. Without tak- . , FIG 450. — ipkiclidts ajax. ing into account the more minute differences these forms can be separated as follows : — (1) The Early-spring Form, Iphiclides ajax marc dins (mar-cel'lus).— This is the form figured here. It expands from two and six tenths inches to two and eight tenths inches ; and the tails of the hind wings are about six tenths inch in length and tipped with white. (2) The Late-spring Form, Iphiclides ajax telamonidcs 380 THE STUDY OF INSECTS. (tel-a-mon'i-des). — This form is a little larger than marcellus and has tails nearly one third longer ; these tails are bordered with white on each side of the distal half or two thirds of their length. (3) The Summer Form, Iphiclides ajax ajax. — The sum- mer form is still larger, expanding from three and two tenths inches to three and one half inches, and has tails nearly two thirds longer than the early-spring form. The life-history of this species has been carefully worked out by Mr. W. H. Edwards. He has shown that there are several generations each year, and that the winter is passed in the chrysalis state. But the early-spring form and the late-spring form are not successive broods ; these are both composed of individuals that have wintered as chrysalids, those that emerge early developing into marcellus, and those that emerge later developing into telamonides. All of the butterflies produced from eggs of the same season, and there are several successive broods, are of the summer form, ajax ajax. The larva feeds upon papaw (Asimina). This insect is found throughout the eastern half of the United States except in the extreme north. Subfamily PARXASSIIN.E (Par-nas-si-i'nae). The Parnassians (Par-nas1 si-ans). The Parnassians differ from the Swallow-tails in lacking the tail-like prolongations of the hind wings and in that the ground-color of the wings is white ; but resemble them in the general plan of the venation of the wings, and in pos- sessing similar scent-organs (osmateria) in the larval state. The wings of the butterflies are usually conspicuously marked with black spots and shades, and with red spots. Only four species have been found in North America. These belong to the genus Parnassius (Par-nas'si-us). They are found only on high mountains or far north. LEPIDOPTERA. 381 Family PiERID^E (Pi-er'i-dae). The Pierids (Pi'e-rids). These butterflies are usually of medium size, but some of them are small; they are nearly always white, yellow, or orange, and are usually marked with black. They are the most abundant of all our butterflies, being common every- where in fields and roads. Some species are so abundant as to be serious pests, the larvae feeding on cultivated plants. The characteristic features of the venation of the wings are the following (Fig. 460): Vein V, of the fore wings is more closely connected with radius than with cubitus, the latter appear- ing to be three-branched ; vein V, of the fore wings coalesces with radius for a considerable distance beyond the apex of the discal cell ; and only three or four of the branches of radius remain distinct. In this family the fore legs are well developed in both sexes, there being no tendency to their reduc- tion in size, as in the two following families. The larvae are usual- ly slender green worms , . . . f 1 c. F»G- 460.— Wings of t'omtfa fret edit*. clothed with short, fine hairs; the well-known Cabbage-worms are typical illus- trations (Fig. 461). The chrysalids are supported by the tail and by a loose girth around the middle. They may be distinguished at a glance by the presence of a single pointed projection in front (Fig. 461). 382 THE STUDY OF INSECTS. Our genera of this family can be separated into three groups, which seem hardly distinct enough to be ranked as FIG. 461. — Pieris rapce, larvae and pupa. subfamilies. These are the Whites, the Yellows, and the Orange-tips. I. The Whites. — The more common representatives of this group are the well-known Cabbage-butterflies. They are white butterflies more or less marked with black. Occa- sionally the white is tinged with yellow ; and sometimes yel- low varieties of our white species occur. About a dozen North American species of this group are known. The Cabbage-butterfly, Pieris rapes (Pi'e-ris ra'pse). —The wings of this butter fly are dull white above, occasionally tinged with yellowish, especially in the female ; below, the apex of the fore wings and the entire FIG. 462.— Pieris rajxz. LEPIDOPTERA. 383 surface of the hind wings are pale lemon-yellow. In the female there are two spots on the outer part of the fore wing besides the black tip, in the male only one (Fig. 462). There is considerable variation in the intensity of the black markings, and in the extent of the yellow tinge of the wings. The larva of this species (Fig. 461) feeds'principally on cabbage, but it also attacks many other cruciferous plants. Its color is the green of the cabbage-leaf, with a narrow, greenish, lemon-yellow dorsal band, and a narrow, inter- rupted stigmatal band of the same color. The body is clothed with very fine short hairs. Pieris rapce is without doubt the most injurious to agri- culture of all our species of butterflies. It is an introduced species, but has spread over the greater part of this coun- try. As it is three-brooded in the North and probably more in the South, it is present nearly the entire season, so that it needs to be fought constantly. Owing to the im- practicability of using poison upon cabbage, and to the fact that the larva bores into the heart of the cabbage beyond the reach of applications to the plant, it is an exceedingly difficult insect to combat. Obviously it is important in fighting this insect to thoroughly subdue the spring and summer broods, so that the bulk of the fighting can be done before the cabbage begins to head. For this purpose pyrethrum and kerosene emulsion have been found most useful. The Gray-veined White, Pieris oleracea (Pi'e-ris ol-e-ra'- ce-a).— The wings are white above and below, with a scarcely perceptible tinge of greenish yellow. Sometimes there is a dark spot on the fore wing between veins V, and VII, , but usually the wings are unspotted. The base of the wings, however, and the basal half of the costa of the front wings, are powdered more or less with dark scales, and the veins of the wings, especially on the lower side, are grayish. This species occurs throughout Canada and in the more 384 THE STUDY -OF INSECTS. northern portions of the United States. The larva feeds on cabbage. The Checkered White, Pontia protodice (Pon'ti-a pro- tod'i-ce). — The two sexes of this species differ greatly in appearance, the female being much more darkly marked than the male. The wings are white, marked above with grayish brown. There is a bar of this color at the end of the discal cell ; beyond this there is in the male a row of three more or less distinct spots, and in the female an almost continuous band of spots. Besides these there is in the female a row of triangular spots on the outer margin of both fore and hind wings, and on the hind wings a submar- ginal zigzag bar. The larva of this species is colored with alternating stripes of bright golden yellow and dark greenish purple, upon which are numerous black spots. It feeds upon cab- bage and other cruciferous plants, and occurs in nearly the whole of the United States. Both this and the preceding species seem to become greatly lessened in numbers by the increase of the imported Pieris rapes. II. The Orange-tips. — These, like the butterflies compris- ing the preceding group, are white, marked with black. Their most characteristic feature is the presence on the lower surface of the hind wings of a greenish network, or a marbled green mottling. This usually shows through the wing so as to appear as a dark shade when the wings are seen from above (Fig. 463). Many species have a con- spicuous orange spot on the api- cal portion of the front wings. This has suggested the common name Orange-tips for the group. But it should be remembered that some species lack this mark, and that in some others it is confined to the males. Nearly ^.-iynchloe olympia. ' all of our species are confined to the far West. The two following occur in the East. LEPIDOPTEKA. 385 The Falcate Orange-tip, A nthocharis genutia (An-thoch'- a-ris ge-nu'ti-a). — In this species the apex of the fore wings is hooked, reminding one of the Hook-tip Moths. In the males there is a large apical orange patch. This butterfly is found throughout the southeastern part of the United States, not including Florida. It occurs as far north as New Haven, Conn. It is nowhere abundant. Synchloe olympia (Syn'chlo-e o-lym'pi-a). — In this species the orange patch is wanting in both sexes. There is a con- spicuous black bar at the end of the discal cell of the fore wings, and the apical portion of these wings is gray, includ- ing a large irregular white band (Fig. 463). This species occurs in the Mississippi Valley. III. The -Yellows. — The Yellows are easily recognized by their bright yellow colors, although in some species whitish forms occur. They abound almost everywhere in open fields, and are common about wet places in roads. To this group belong the larger number of our Pierids. The Clouded Sulphur, Eurymus philodice ( Eu'ry-m us phi- lod'i-ce). — The wings above are rather pale greenish yellow, with the outer borders black- ish brown. Figure 464 repre- sents the male ; in the female the border on the fore wings is broader, and contains a sub- marginal row of yellow spots. The discal dot of the fore FIC. ^.-/r^,—* //./A.,//, wings is black, that of the hind wings is orange. The under surface is sulphur-yellow. This species is dimorphic. The second form is repre- sented only by the female sex, and differs in having 1 ground-color of the wings white instead of yellow. The Clouded Sulphur occurs from the mouth of the , Lawrence to South Carolina and westward to the Mountains. Its larva feeds upon clover and minosae. 386 THE STUDY OF INSECTS. The Orange Sulphur, Eurymus eurytheme (E. eu- ryth'e-me). — This species closely resembles philodice in- size, shape, and markings. The typical form differs from philodice in being of an orange color above instead of a yellow. The Orange Sulphur is a Western species, occurring in the Mississippi Valley and west to the Pacific Ocean. It is one of the most polymorphic of all butterflies ; the forms differ so much in appearance that four or five of them have been described as distinct species. The larva feeds on clover. The Dog's-head, Zerene casonia (Ze-re'ne cae-so'ni-a.) — The wings are lemon-yellow above, bordered on the outer margin with black. On the hind wings the border is nar row, but on the fore wings it is broad. The outline of the yellow of the fore wings suggests a head of a dog or of a duck, a prominent black spot on the discal vein serving as the eye. This is an abundant species in the Southeastern and Southwestern States, extending from the Atlantic to the Pacific. The larva feeds on clover. The Black-bordered Yellow, Xanthidia nicippe (Xan- thid'i-a ni-cip'pe). — The wings above are bright orange, marked with blackish brown as follows : on the fore wings a narrow bar at the apex of the discal cell, the apical portion of the wings, and the outer margin ; on the hind wings, the outer margin. In the female the outer marginal band is in- terrupted at the anal angle of each wing, and on the hind wings it may be reduced to an apical patch. The expanse of wings is from one and six tenths inches to one and nine tenths inches. The species occurs from Southern New England to Florida and west to Lower California. The larva feeds on several species of Cassia. The Little Sulphur, Eurema lisa (Eu-re'ma li'sa). — Although this species is larger than the following one it is considerably below the average size of our yellows, the LEP1DOPTEKA. 387 larger specimens expanding less than one inch and a half. The wings are canary-yellow above, with the apex of the fore wing and the outer margin of both fore and hind wings blackish brown. The border of the hind wing is narrow and sometimes wanting. The distribution of this species is similar to that of the preceding. The larva feeds on Cassia. The Dainty Sulphur, Nathalis iole (Na-tha'lis i'o-le). — This little butterfly can be distinguished from all others de- scribed here by its small size, as it expands only from less than one inch to one and one fifth inches. It is of a pale canary-yellow color, with dark brown markings. There is a large apical patch on the fore wings, and a broad band par- allel with the inner margin ; on the hind wings there is a stripe on the basal two thirds of the costa, and spots on the ends of the veins ; these are more or less connected on the margin of the wing, especially in the female.' This species also is found from Southern New England to Florida and west to Lower California. It, too, feeds on Cassia. The Cloudless Sulphur, Callidryas cubule (Cal-lid'ry-as eu-bu'le). — This large butterfly differs greatly in appearance from those described above. It expands two and one half inches. The wings above are of uniform bright canary- yellow. In the male they are without spots, except fre- quently an inconspicuous brown dot at the tip of each vein, and a lilac-brown edging of the costal border. In«the female there is a discal dot on the fore wing and a mar- ginal row of brown spots at the ends of the veins. This is a southern species which occasionally extends as far north on the coast as New York City, and in the Missis- sippi Valley as far as Southern Wisconsin. The larva feeds on Cassia. 388 THE STUDY OF INSECTS. Family LYC/ENID^E (Ly-caen'i-dae). The Gossamer-winged Butterflies. The family Lycaenidae includes butterflies which are of small size and delicate structure. In size they resemble the smaller Hesperiidae ; but they can be distinguished at a glance from the skippers, as they present an entirely differ- ent appearance. The body is slender, the wings delicate and often brightly colored, and the club of the antenna straight. The antennae are nearly always ringed with white, and a conspicuous rim of white scales encircles the eyes. An easily-observed combination of characters by which the members of this fam- ily can be distinguished is the absence of one or two of the branches of radius of the fore wings, this vein being only three- or four-branched, and the origin of vein V, of the fore wings at or near the apex of the discal cell (Fig. 465). In all other butterflies occurring in our fauna in which radius is only three- or four-branched, vein V, of the fore wings coalesces with radius for a considerable distance beyond the apex of the discal cell. An excep- 465.-wings of chrysophanus thoe. tion to the characters of the Lycaenidae is presented by Feniseca, as indicated in the table of families, p. 375. A remarkable characteristic of this family is that while in Vllt PLATE VI. fa* m i m LEPIDOPTERA. 389 the female the front legs are like the other legs, in the male they are shorter, without tarsal claws, and with the tarsi more or less aborted. This reduction of the fore legs is carried even farther in the next family, where it extends to both sexes, and the fore legs are unused. The caterpillars of the Lycaenidae present a very unusual form, being more or less slug-like, reminding one of the larvae of the Eucleidae. The body is short and broad ; the legs and prolegs are short and small, allowing the body to be closely pressed to the object upon which the insect is moving — in fact some of the species glide rather than creep ; and the head is small, and can be retracted more or less within the prothorax. The body is armed with no conspic- uous appendages ; but some of the species are remarkable for having honey-tubes which can be pushed out from the seventh and eighth abdominal segments, and through which honey-dew is excreted for the use of ants. Certain other species are remarkable in being carnivorous ; one American species feeds exclusively upon plant-lice. The chrysalids are short, broad, ovate, and without angu- lations. They are attached by the caudal extremity, and by a loop passing over the body near its middle. The ventral aspect of the body is straight and often closely pressed to the object to which the chrysalis is attached. The Lycaenidse include two subfamilies; these can be be separated as follows : — A. Vein II of the hind wings without a branch near the base of the wing (Fig. 465) .................... ......... LYCJSNINAS. A A. Vein II of the hind wings giving off a spur (the tip of vein I) near the base of the wing. p. 394 ................... LEMONIIN^. Subfamily LYC^NIN^: (Ly-cae-ni'nse). The Common Gossamer-winged Butterflies. This subfamily includes all of our common members of the Lycamidre ; it is composed of three well-marked groups 390 THE STUDY OF INSECTS, of gene/a, which have been distinguished as the Coppers, the Blues, and the Hair-streaks. I. The Coppers. — The Coppers are easily distinguished from other gossamer-winged butterflies by their orange-red and brown colors, each with a coppery tinge, and conspicu- ous black markings. They are the stoutest of the Lycsenidae. About twenty species are known to occur in this country ; the three following will serve-as illustrations: — The American Copper, Heodes kypophlaas (He-o'des hyp-o-phlae'as). — This is the most common of our coppers in the Northeastern States and in Canada. Its range ex- tends also along the boundary between the United States and Canada to the Pacific Ocean, and southward into Cali- fornia ; and in the east along the Alleghany Mountains south to Georgia. It is represented on Plate I (Fig. 4). The fore wings are orange-red above, spotted with black, and with a blackish brown outer border ; the hind wings are coppery brown, with a broad orange-red band on the outer margin ; this band is indented by four black spots. The larva feeds on the common sorrel (Rumex acetosella). The Bronze Copper, Chrysoplianus thoe (Chrys-o-pha'nus tho'e). — This is larger than the preceding species, the wings expanding one and one half inches or more. In the male the wings are coppery brown above, spotted with black, and with a broad orange-red band on the outer margin of the hind wings. The female differs in having the fore wings orange-red above, with prominent black spots. This species occurs in the Middle and Western States from the Connecticut Valley to Nebraska. The larva feeds on curled dock (Rumex crispus). The Wanderer, Feniseca tarquinius (Fe-nis'e-ca tar-quin'i- us).— This butterfly can be readily distinguished from all other Lycaenids in our fauna by the fact that vein V, of the fore wings coalesces with radius for a considerable dis- tance beyond the apex of the discal cell. The upper surface of the wings is dark brown, with a large, irregular, orange- LEPIDOP TERA . 39 1 yellow patch on the disk of the fore wing, and one of the same color next the anal angle of the hind wing. This species is of unusual interest, as the larva is carniv- orous in its habits. It feeds on plant-lice ; and, so far as observed, it feeds only on the woolly aphids. It is found more often in colonies of the Alder Blight (Schizoneura tes- sellata) than in those of the allied species. It is found from Maine to Northern Florida and westward to Kansas. Jt is a very local insect, being found only in the neighborhood of water where alder grows. II. The Blues. — The Blues may be distinguished from the other gossamer-winged butterflies by the slender form of the body, and the blue color of the upper surface of the wings. About fifty North American species have been de- scribed; but most of these occur only in the far West. This is a rather difficult group to study owing to the fact that in several cases a single species exists under two or more distinct forms, and also that the two sexes of the same species may differ greatly. It often happens that two indi- viduals of the same sex but of different species resemble each other more closely in the coloring of the upper sur- face than do the two sexes of either of the species. In each of our eastern species the upper surface of the wings of the female is much darker than that of the male. The Spring Azure, Cyaniris pseudargiolus (Cy-a-ni'ris pseud-ar-gi'o-lus). — In this species the hind wings are with- out tails, the eyes are hairy, and the lower surface of the wings is pale ash-gray. This combination of characters will distinguish it from all other blues occurring in the Eastern United States. But the species is not confined to this re- gion, as it occurs in nearly all parts of the United States and in a large part of Canada. This butterfly exhibits polymorphism to the greatest degree of any known species ; nine or ten forms have been described. Two of these are represented on Plate VI (Figs, i and 7). The larva feeds on the buds and flowers of various 392 THE STUDY OF INSECTS. plants, especially those of Cornus, Cimicifuga, and Actino- meris. They are frequently attended by ants for the sake of the honey-dew which they excrete through tubes that they push out from the seventh and eighth abdominal seg- ments. The Tailed Blue, Everts comyntas (E-ve'res co-myn'tas). — The butterflies of the genus Everes can be distinguished from our other blues by the presence of a small tail-like prolongation of the hind wing. This is borne at the end of vein VII. Our common species (E. comyntas] is distributed over nearly all parts of North America. The male is dark purplish violet above, bordered with brown ; the female is dark brown, sometimes flecked with bluish scales. In the Eastern United States this is the only species of the genus. The larva feeds upon clover and other leguminous plants. III. The Hair-streaks. — The Hair-streaks are distinguished from the other Lycaeninae by the fact that radius of the fore wings is only three-branched. They are usually dark brown, with delicate striped markings on the lower surface of the wings, which suggested the com- mon name given above ; but some species are brilliantly marked with me- tallic blue or green. The hind wings are also commonly furnished with deli- cate tail-like prolongations (Fig. 466). The fore wings of the male often bear a small dull oval spot near the middle of the costal part of the wing, the dis- .c. &.-Th., with three mem- branous lobes beneath the tarsal claws (Fig. 495). p.456 ...................... LEPTID*. KK. With only two membranous lobes beneath the tarsal claws, p. 464 ......... THEREVID*. II. Cell V, obliterated by the coalescence of veins V, and VIIi. 426 THE STUDY OF INSECTS. ]. Third segment of antennae without bristle or style ; vein Vi ending at or before the apex of the wing (Fig. 568). p. 465 SCENOPINIDJE. JJ. Third segment of antennae usually with bristle or style ; vein Vi ending beyond the apex of the wing. K. Vein Vila extending free to the margin of the wing or coalesced with vein IX for a short distance (Fig. 564). p. 463 BOMBYLID^E. KK. Vein Vila joining vein IX far from the margin of the wing, often extending towards the base of the wing (Fig. 569). p. 466. EMPIDIDJE. EE. Vein III with not more than three branches. F. Wings lanceolate, and with no cross-veins except at the base (Fig. 572). p. 469 LONCHOPTERID;E. FF. Wings not of the type represented by Figure 572. G. Flies with a very small head ; with the thorax and abdomen inflated, giving the body a hunchback-like appearance, and with the alulets very large. The empodiapulvilliform, i.e., with three membranous lobes beneath the tarsal claws, p. 458 ACROCERID^E. GG. Head of ordinary size or very large ; form of thorax and abdomen various ; alulets either large or small. The empodia not pulvilliform, i.e., only two membra- nous lobes beneath the tarsal claws. H. Vein VIIj appearing as a cross-vein or curved back towards the base of the wing (Figs. 569, 588). I. Antennae with a terminal style or arista, p. 466. EMPIDID^E. II. Antennas with a dorsal arista. J. Proboscis rudimentary ; mouth-opening small ; palpi wanting, p. 477 CESTRID^E. JJ. Proboscis not rudimentary ; palpi present. K. Head with a suture immediately above the antennae through which the ptilinum is pro- truded and withdrawn (Fig. 587). p. 479. MUSCID^E. KK. Head without such suture, p. 466. EMPIDID^E. HH. Vein VII3 not coalesced with vein IX to such an DIPTERA. 427 extent as to cause the free part to appear like a cross-vein. I. Antenna with a terminal style or bristle. J. Antenna with a terminal bristle, p. 474. PLATYPEZIDjE. JJ. Antenna with a terminal style. K. Front with grooves or a depression beneath the antennae, p. 476 CONOPID^E. KK. Front convex beneath the antennze. P- 47o SYRPHJD/E. II. Antenna with dorsal bristle. J. Head extremely large, and with nearly the en- tire surface occupied by the eyes (Fig. 577). P- 473 PIPUNCULIDJE. JJ. Head not of the type represented by Figure 577- K. Wings with a vein-like thickening, the spu- rious vein, between veins III and V (Fig. 574). p. 47° SYRPHIDVE. KK. Wings without a spurious vein. L. Front with grooves or a depression beneath the antennas, p 476 CONOPIDJE. LL. Front convex beneath the antennae. p. 470 SYRPHID.*. AA. Flies in which the abdomen is indistinctly segmented, and the two legs of each segment are widely separated by the broad ster- num. The adults live parasitically upon birds, mammals, or the Honey-bee. B. Compound eyes present ; wings present or absent, p. 487. HIPPOBOSCID^E. BB. Both compound eyes and wings absent. C. Halteres present; tarsal claws of ordinary form. Adults parasite upon bats. p. 489 NYCTERIBIID,E. CC. Halteres absent ; last segment of tarsus with a pair of comb- like appendages, p. 489 BRAULID^:. Suborder ORTHORRHAPHA (Or-thor'rha-pha). The Straight-seamed Flies. To this suborder belong those families of flies in which the pupa escapes from the larval skin through a T-shaped 428 THE STUDY OF INSECTS. opening, which is formed by a lengthwise split on the back near the head-end and a crosswise split at the front end of this (Fig. 498). In a few members of this suborder (i.e., some of the Cecidomyiidae) the pupa escapes FlG- <98. through a crosswise split between the seventh and eighth abdominal segments. The pupae are usually either naked or enclosed in the last larval skin, the puparium ; but the pupae of some of the gall-gnats, Cecidomyiidae, are enclosed in cocoons. The adult flies do not possess a frontal lunule. See footnote page 416. Family PSYCHODID^; (Psy-chod'i-dae). The Moth-like Flies. There may be found frequently upon windows and on the lower surface of the foliage of trees small flies which have the body and wings densely clothed with hair and which resemble tiny moths in appear- ance. The wings are broad, and when at rest slope at the sides in a roof-like manner or are held horizontally in such a way as to give the FlG 499._A insect a triangular outline (Fig. 499). moth-iike fly. The moth-like appearance of these insects is sufficient to distinguish them from all other flies. The venation of the Vila FIG. 500.— Wins of a moth-like fly. DIPTEKA. 429 wings (Fig. 500) is also very peculiar. All of the longitu- dinal veins separate near the base of the wing except veins III, and III, and veins V, and Va. In some forms veins III4 and III, are distinct, as shown in the figure; in others they coalesce completely, so that radius is only four-branched. In this case there is only a single vein between the two forked veins. The antennae are long and slender, and are clothed with whorls of hairs (Fig. 501). Those of the male are longer; and in the species figured the two basal segments are clothed with scales like those of the Lepidoptera. Scales of this form occur also on the wings, palpi, and legs of certain species. Only a few of the American species have been described ; these have been FIG. 501. — Antennae of Psy- placed in the genus Psyclwda ; the <*&££££«££ early stages of none of them have g£«Mta3TSd;ti£ *J been observed. The larvae of some enlarged. European species inhabit cow-dung, and others live in water. They have a pair of spiracles at each end of the body. As regards the structure of their wings these flies are very distinct from all others. The pre-anal area, that part lying in front of vein VIII. presents an extremely generalized form. This is shown by the outline of the wing (a line drawn lengthwise of the wing through its centre will divide it into two similar parts), the small extent to which the veins coalesce, and the fact that the maximum number of veins is present. On the other hand, the anal area is so reduced as to be barely represented. The dotted line in the figure represents the position of what is left of the anal furrow (i.e., vein VIII). Family TlPULlD^E (Ti-pu'li-dae). The Crane-flies. The crane-flies are mosquito-like in form ; but they are usually very much larger than mosquitoes. The body is long and slender, the wings narrow, and the legs very 430 THE STUDY OF INSECTS. long (Fig. 502). This family includes the larger members of that series of flies in which the antennae are thread-like ; but it also includes some species that are not larger than certain mosquitoes. The most distinctive feature of crane- flies is the presence of a transverse V-shaped suture on the dorsal side of the mesothorax (Fig. 503). a crane- fly showing the V-shaped suture. FIG. 502. — A crane-fly. The wings are long and narrow. In a few genera vein III is five-branched, and the branches separate near the middle of the wing (Fig. 504) ; but usually the number of FIG. 504.— Wing of Protofilasa fiichii. (After Osten Sacken.) branches is reduced to three or four; and those that remain distinct separate near the apex of the wing (Fig. 505). Cell V, is divided into two parts by a cross-vein ; the branches of vein VII like those of vein III separate near the distal end of the wing ; and the margin of the wing is strengthened by an ambient vein. DIPTERA. 431 The structure of the ovipositor is also quite distinctive, being composed of two pairs of long, horny, pointed valves. These are fitted for depositing the eggs in the ground, or in other firm substances. The larvae of most species live in the ground ; and some of them destroy grass and grain by gnawing the young plants just below the surface of the soil. Those of other species live in various situations, as in water, in decaying wood, in fungi, and even on the leaves of plants. The larvae FIG. sos—Wing of Tipula abdominatts. of this family have either a single pair of spiracles situated at the hind end of the body, or they have two pairs, one at each end of the body. The pupae are not enclosed in a puparium, and bear transverse rows of hairs, bristles, or spines, which enable them to work their way out from the earth when about to transform. Crane-flies often appear in great numbers, flying over meadows and pastures. But in most cases their power of flight does not seem to be well developed ; for they fly slowly, and only a short distance at a time. Some species, however, sustain themselves in the air for long periods. This is especially true of some of the smaller species ; which often collect in swarms at twilight, forming a small cloud, and dancing up and down like some of the midges. But even with these the flight is poor compared with that of the more specialized families, as the Syrphidae or the Muscidse. Their ability to walk is also poor ; for they use their long legs awkwardly, as if they were in the way. This has sug- gested the rhyme : — " My six long legs, all here and there, Oppress my bosom with despair." 432 THE STUDY OF INSECTS, Not only are the legs of crane-flies poorly fitted for loco, motion, but they are so feebly attached to the body that they are easily broken off ; however, the loss of a few legs does not seem to be a serious matter to one of these insects. Yet from what we know of the laws of development we are forced to believe that the peculiar form of the legs has been attained in order to fit them to perform better some impor- tant function. It may be that the great length of the legs is correlated with the unusual length of the abdomen and ovipositor, and enables the insect to oviposit in a better manner than would otherwise be possible. When about to lay her eggs, the female stands nearly upright and, bringing the abdomen at right angles to the surface of the earth, thrusts the ovipositor into the ground. After placing one or two eggs in the hole thus made, she moves forward a few steps and repeats the operation. Family BLEPHAROCERID^; (Bleph-a-ro-cer'i-dae). The Net-winged Midges. The net-winged midges are extremely remarkable in- sects ; for in certain respects the structure of the adults is very peculiar, and the larvae appear much more like Crusta- ceans than like Insects. The adults are mosquito-like in form ; but they differ from all other insects in having the wings marked by a net- work of fine lines which extend in various directions and are not influenced at all by the veins of the wing (Fig. 506) ; they are, however, quite constant in their position in the species that we have studied. When a wing is examined with a microscope, the fine lines are seen to be slender thickenings extending along the courses of slight folds in the wing. The significance of these folds is evident when a net-winged midge is observed m the act of issuing from its pupa-skin. When the wing is first pulled out of the wing-sheath of the pupa, that part of DIPTERA. 433 it which is crossed by the fine lines is plaited somewhat like a fan and folded over the other portion. By this means the wing, which is fully developed before the adult emerges, is packed within the wing-sheath of the pupa, which is much shorter and narrower than the wing. When the wing is FIG. 506.— Wing of Blepharocera. finally unfolded, it does not become perfectly flat, but slight, alternating elevations and depressions remain, show- ing the positions of the former folds, a permanent record of the unique history of the wings of these insects. Ordinarily the wings of insects, while still in the wing- sheaths of the pupa, are neither longer nor wider than the wing-sheaths, but expand after the adult emerges from the pupa skin. Usually it takes considerable time for the wings to expand and become fit for flight ; and during this interval the insect is in an almost helpless condition. In certain caddice-flies that emerge from swiftly-flowing water, the time required for the expansion of the wings has been reduced to the minimum (see pp. 189, 190). In the net- winged midges, which also emerge from swiftly-flowing water, the difficulty is met by the wings reaching their full development before the adult leaves the pupa-skin. It is only necessary when the adult emerges from the water that it should unfold its wings to be ready for flight. The members of this family have three simple eyes. Each compound eye is divided into two parts: an upper half, in which the ocelli are very large; and a lower half, in 434 THE STUD Y OF INSECTS. which the ocelli are small. The antennae are thread-like, but are not furnished with whorls of long hairs (Fig. 507). The legs are very long. On the dorsum of the meso- thorax there is on each side, beginning just in front of the base of the wing, a well-marked suture, like that of the crane-flies ; but the two do not meet so as to form a continuous V-shaped suture as in the Tipulidae. In some species at least there are two kinds of females, which differ somewhat in the shape of the FIG. s<>7. head. These two forms also differ in habits, one being blood-sucking, the other feeding upon nectar. The adults may be found resting on the foliage of shrubs and trees on the margins of mountain-brooks, or dancing in the spray of waterfalls. The immature forms of these insects are even more wonderful than are the adults. The larvae live in water, in swiftly-flowing streams, where the water flows swiftest. We have observed the transformations of Blepharocera capitata (Bleph-a-roc'e-ra cap-i-ta'ta), which is abundant in some of the ravines near Ithaca, N. Y. The larvae of this species are readily seen on account of their black color, and are apt to attract attention on account of their strange form (Fig. c b a 508, a). At first sight the body appears to consist of only seven segments, but careful examina- tion reveals the presence of smaller segments alternating with these. Each of the larger segments except the last bears a pair of conical, leg-like appen- dages. On the ventral side of the body (Fig. 508, d) each of the seven larger segments except the last bears a sucker, the cavity of which extends far into the body, and each FIG. 508. — Blepharocera . a, larva, dor- sal view ; 6, larva, ventral view ; c9 puparium. DIPTERA. 435 of these segments except the first bears two tufts of tracheal gills ; but those of the last segment are united. The head, which forms the front end of the first of the seven larger divisions, bears a pair of slender antennae ; each of these consists of a very short basal segment and two long segments; at the tip of the last of these there is a pair of minute appendages and a bristle. The suture between the head and the remaining part of the first division is best seen on the ventral side of the body. On the dorsal side a suture may be seen dividing the last division into two segments. The pupa-state is passed in the same place as the larval. Like the larvae the pupae are very conspicuous on account of their black color, and are apt to -occur like the larvae closely clustered together. The pupa is not enclosed in the larval skin, and differs greatly in form from the larva. On the dorsal side the skin is hard, forming a convex scale over the body (Fig. 508, c] ; and the thorax bears a pair of breath- ing-organs ; on the ventral side the skin is very delicate, soft, and transparent ; so that the developing legs and wings may be easily seen when the insect is removed from the rock. The pupae cling to the rock by means of six suckers, three on each side near the edge of the lower surface of the abdo- men ; and so firmly do they cling that it is difficult to re- move specimens without breaking them. We have watched the midges emerge from their pupa- skins and escape from the water. The pupae occurred in groups so as to form black patches on the rocks. Each one was resting with its head down stream. Each midge on emerging forced its way out through a transverse rent be- tween the thorax and abdomen. It then worked its body out slowly, and in spite of the swift current held it vertical. The water covering the patch of pupae varied from one fourth to one half inch in depth. In the shallower parts the adult had no trouble in working its way to the surface still clinging to the pupa-skin by its very long hind legs. 436 THE STUD Y OF JNSECTS. While still anchored by its legs the midge rests on the sur- face of the water for one or two seconds and unfolds its wings; then freeing its legs it takes flight. The adults emerging from the deeper water were swept away by the current before they had a chance to take wing. The time required for a midge to work its way out of the pupa-skin varied from three to five minutes. Family Dixm^: (Dix'i-dae). The Dixar-midges. These midges closely resemble mosquitoes in size and form ; but they are easily distinguished by the venation of their wings (Fig. 509). FIG. 509.— Wing of Dixa. The wing-veins are not furnished with scales, and are distinct over the entire surface of the wing ; vein I is pro- longed into an ambient vein ; vein II is well developed, but is short, ending in the margin of the wing near its middle, ana before the first fork of vein III ; vein III is four-branched ; vein V is two-branched ; cell Va is not divided by a cross- vein ; and vein III, extends parallel to the mar- gin of the wing to a point on the outer end of the wing. The antennae (Fig. 510) are six- teen-jointed, and differ but slightly in the two sexes ; the legs are very long and slender ; and he caudal end of the abdomen of the male is FlG 5IO enlarged. DIPTERA. 437 The family includes only a single genus, Dixa. We have found the adult midges common on rank her- bage, growing in a swampy place, in a shady forest. Family CULICID^: (Cu-lic'i-dae). The Mosquitoes. The form of mosquitoes is so well known that it would be unnecessary to characterize the Culicidae were it not that there are certain mosquito-like insects that are liable to be mistaken for members of this family. The mosquitoes are small flies, with the abdomen long and slender, the wings narrow, the antennae plumose in the males (Fig. 5 1 1), and usu- ally with a long, slender, but firm proboscis. The thorax lacks the transverse V-shaped su-ture characteristic of the crane-flies ; and vein V of the wings is only two-branched (Fig. 512): But the most distinctive feature Fl£ SIuIit" of mosquitoes is a fringe of scale-like hairs /"• '«"">«• on the margin of the wing and also, in all known American forms, on each of the wing-veins. IX FIG. 512.— Wing of Culex. The larvae of mosquitoes, so far as they are known, are aquatic. But it is probable that some species breed in the ground, for mosquitoes occur in arid regions far from water. The transformations of those species with aquatic larvae are easily observed. The immature forms may be found in 438 THE STUDY OF INSECTS. pools of stagnant water, in watering-troughs, and in ex- posed receptacles of rain-water. The long, slender eggs are laid side by side in a boat- shaped mass, on the surface of the water (Fig. 513). They FIG. 513.— A glass of water containing eggs, larvae, and pupae of mosquitoes. hatch in a few days, and the larvae escape from the lower ends into the water. The larvae are well known, and are commonly called " wigglers," a name suggested by their wriggling motion as they swim through the water. The larva (Fig. 514, a) has a large head and thorax and a slender abdomen. The next to the last abdominal segment bears a breathing-tube ; and when the larva is at rest it hangs head down- ward in the water, with the opening of this tube at the surface (Fig. 513). At the end of this tube there is a rosette of plate-like lobes (Fig. 515, a), which, floating on the surface of the water, keeps the larva in posi- tion when at rest. The larva grows rapidly, and after a few DIPTERA. 439 molts changes into a club-shaped pupa, the head and thorax being greatly enlarged (5 14, b}. With this transformation a remarkable change takes place in the respi- ratory system. There are now two breath- ing-tubes, and these are borne by the thorax. One of these tubes is represented greatly enlarged by Figure 5 1 5, #. At the tail-end of the body there is a pair of leaf- like appendages, with which the insect breathing-tube of larva; - b, breathing-tube of swims ; for the pupae of mosquitoes, and PuPa- also of certain midges, differ from the pupae of other insects in being active. The pupa state lasts only a few days ; then the skin splits down the back, and the winged mosquito carefully works itself out and cautiously balances itself on the cast skin, using it as a raft, until its wings are hardened so that it can fly away. The larvae of mosquitoes are doubtless beneficial insects, for they feed on decaying matter in water, and thus act as scavengers ; but the annoyance caused by the bites of the adult females more than counterbalances this good. The males of mosquitoes neither sing nor suck blood;* they are said to feed on the sweets of flowers. These pests can be repelled by smoke and by certain strong-smelling substances. In regions where they abound it is customary to build smudges in the evening for this purpose ; and sportsmen anoint their faces and hands with aromatic ointments. The best of these is made of mutton tallow scented with camphor and oil of pennyroyal; a mix- ture of oil of tar and oil of pennyroyal is also used. It often happens that plagues of these pests are bred in receptacles of rain-water standing near dwellings ; such re- ceptacles should not be left open unnecessarily. When the breeding-places are ponds of limited extent the larvae and *E. Ficalbi states that he has observed two Italian species in which both sexes suck blood. Bull. Soc. Ent. Ital. 1889, p. 25. 440 THE STUD Y OF INSECTS. pupae can be destroyed by pouring a small quantity of kero- sene on the water ; this method of destroying them was first suggested by Mr. L. O. Howard. Family CHIRONOMID^E (Chir-o-nom'i-dae). The Midges. The members of this family are more or less mosquito- like in form. The abdomen is usually long and slender ; the wings narrow ; the legs long and delicate ; and the antennae, especially in the males, strongly plumose (Fig. 516). In fact many of these insects are commonly mistaken for mosquitoes; but only a few of them can bite, the FIG. 316.— Antennae of , , . . . chironomus. /, female ; greater number being harmless. The midges are most easily distin- guished from mosquitoes by the structure of the wings (Fig. 517)- These are furnished with fewer and usually less FIG. 517. — Wing of Chironomus. distinct veins; and the veins, although sometimes hairy, are not fringed with scale-like hairs. There is a marked contrast between the stouter veins near the costal border of the wing and those on the other parts of the wing, which seem to be fading out. The costal vein is not prolonged into an am- bient vein, beyond the apex of the wing. The name midge has been used in an indefinite way, some writers applying it to any minute fly. It is much better, however, to restrict it to members of this family DIPTERA. 441 except where it has become firmly established as a part of a specific name. The Wheat-midge and the Clover-seed Midge are examples of names of this kind ; it would not be wise to attempt to change these names, although the insects they represent belong to the Gall-gnat family, and hence are not true midges. Midges often appear in large swarms, dancing in the air, especially towards the close of day. Professor Williston states that, over meadows in the Rocky Mountains, he has seen them rise at nightfall in most incredible numbers, pro- ducing a buzzing or humming noise like that of a distant waterfall, and audible for a considerable distance. The larvae are either aquatic or terrestrial; they have two pairs of spiracles, one at each end of the body, or are furnished with tracheal gills. Some of the pupae are free and active, others are quiescent ; some of the latter remain partially enclosed in the split larval skin. Many of our species belong to the genus Chironomus (Chi-ron'o-mus). These are mosquito-like in form, but vary greatly in size, some being smaller than our common mos- quitoes, and others much larger. The head is small, the snout, comparatively short, and the antennae of the males very bushy. The larvae so far as they are known are aquatic. Many of them are blood-red in color ; and as they live in standing water they are sometimes found in vessels contain- ing rain-water, where they appear like bits of animated red thread. The pupae of this genus, like those of mosquitoes, are active. To the genus Ceratopogon (Cer-a-to-po'gon) belong the small midges commonly known as punkies. Of these there are many species, which vary greatly in size and color. The body and legs are not as slender as in the preceding genus, and consequently the insects appear much less mos- quito-like. Certain minute species are sometimes very abundant, and extremely annoying on account of their bites. We have found them exceeding troublesome in the Adiron- 442 THE STUDY OF INSECTS, dack Mountains. The larvae live under the bark of decaying branches, under fallen leaves, and in sap flowing from wounded trees. Family MYCETOPHILID^: (My-cet-o-phil'i-dse). The Fungus-gnats. These flies are of medium or small size, and more or less mosquito-like in form. They are most easily recognized by the great length of the coxae (Fig. 518, c\ and the fact that all the tibiae are furnished with spurs. They also differ from the closely-allied families in lacking, as a rule, whorls of hairs on the an- tennae of the males (Fig. 519), and in possessing ocelli. At first sight considerable varia- FiG.5i9. tjon seems to exjst jn tjie venation of the wings as shown in the three wings represented in Figure 520 ; but in reality the variations are comparatively slight. Vein I extends along the margin of the wing to the end of vein III4+6. Vein II varies in length. Vein III pre- serves three branches in the more generalized form (Fig. 520,0); in some genera veins III, and IIIs+3 coalesce from the apex of the wing backward for a greater or less distance so that the base of vein 111.,+,, appears like a cross vein (Fig. 520, fr); this coalescence may be complete, in which case vein III is only two-branched (Fig. 520, c). Vein V is also two-branched. It should be observed that the cross-vein III-V extends more or less obliquely or even lengthwise of the wing; while the base of vein III4+6 may extend trans- versely, and then is liable to be mistaken for a cross- vein (Fig. 520, b, c). The flies are often found in great numbers on fungi and in damp places where there is decaying vegetable matter. They are active, and leap as well as fly. D1PTERA. 443 HU+3 The larvae are gregarious, and live in fungi and in decay- ing vegetable matter. They may be found in the fungi growing on logs and trees, in the vegeta- ble mould among dead leaves, under bark, and sometimes in cow-dung. They have eight pairs of spiracles. One spe- cies, Sciara mail (Sci'a-ra ma'li), feeds on ripe apples, es- pecially those that have been previously perforated by the Codlin-moth. In this family the larva has a distinct head. The pupa is not enclosed in the skin of the larva ; but in some genera1 the transformations are undergone in a delicate cocoon. The larvae of some species of the genus Sciara often attract attention on account of a strange habit they have of sticking together in dense patches. Such assemblages of larvae are frequently found under the bark of trees. But what is more remarkable is the fact that when the larvae are about to change to pupae an assemblage of this kind will march over the surface of the ground, presenting the appear- ance of a serpent-like animal. Such a congregation is com- monly spoken of as a Sciara-army-worm. Examples have been described that were four or five inches wide and ten or twelve feet long, and in which the larvae were piled up from 520. — Wings of fungus-gnats. (The drawings are after Winnertz ; the lettering is original.) 444 THE STUDY OF INSECTS. four to six deep. The larvae crawl over each other so that the column advances about an inch a minute. Family CECIDOMYIID^E (Cec-i-do-my-i'i-dae). The Gall-gnats. The gall-gnats are minute flies which are extremely delicate in structure. The body and wings are clothed with long hairs, which are easily rubbed off. The antennae are long, sometimes very long, and usually with a whorl of hairs on each seg- ment (Fig. 521); the legs are slender and quite long, but the coxae are not greatly elongate, and the tibiae are without spurs ; the wing-veins (Fig. 522) are greatly reduced in number ; the anal veins being entirely wanting, and vein V wanting or merely FIG. s«- — Antennae represented by a slight, unbranched fold, male; /. female', To this family belong the smallest of enlarged more than that of the male. the midge-like flies. On account of their minute size, the adult flies are not apt to attract the at- tention of the young student. But the larvae of many vii7 FIG. 522.— Wing of gall-gnat. species cause the growth of galls on plants ; some of which are sure to be found by any close observer. Other species arrest the growth of the plants they infest, and thus cause DIPTERA. 445 very serious injury; in this way the amount of a crop of grain is often greatly reduced. The larvae are small maggots, with nine pairs of spiracles. Many species are brightly colored, being red, pink, yellow, or orange. In almost every case a larva belonging to this family can be recog- nized as such by the presence of a horny piece on the lower side of the body, be- tween the second and third segments (Fig. FIG. 523. — Head-end of . _,, . . . 11 j . i i_ ,1 larva showing the 523). This piece is called the breast-bone, breast-bone. Its homology and use have not been definitely determined. The different species vary as to the method of under- going their transformation ; in some the pupa is naked ; in others the pupa is enclosed in the dried skin of the larva ; and in still others it is enclosed in a delicate cocoon. One of the most common and conspicuous of the galls made by gall-gnats is the Pine-cone Willow-gall (Fig. 524). This often occurs in great abundance on the tips of twigs of the Heart - leaved Willow (Salix cordatd). The gnat that causes the growth of this gall is Cecidomyia strobiloides (Cec-i-do-my'i-a strob-i- loi'des). The gall is a deformed and enlarged bud; the lengthening of the stem is checked by the injury caused by the larva; but leaves FIG. 524.— The Pine-cone Willow-gall. Continue to be devel- oped which results in the cone-shaped growth. The larva remains in the heart of the gall throughout the summer and winter, changing to a pupa early in the spring. The adult 446 THE STUDY OF INSECTS. emerges soon afterward, and lays its eggs in the newly- started buds of the willow. There is a guest gall-gnat, Cecidomyia albovittata (C. al- bo-vit-ta'ta), which breeds in large numbers between the leaves composing the Pine-cone Willow-gall. The larvae of this gnat do not seem to interfere in any way with the development of their host, there being abundant food in the gall both for the owner of the gall and for its numerous guests. The Clover-leaf Midge, Cecidomyia trifolii(C. tri-fo'li-i). — The leaflets of white clover are sometimes infested by white or orange-colored mag- gots which fold the two halves of the leaflet together. From one to twenty of these larvae may be found in a single leaflet. When f u 1 1- grown the larvae make . in. (From the Author's -cocoons, and undergo their transformations within the folded leaflet. In Figure 525 an infested leaf containing cocoons is represented natural size, also a larva and an adult gnat, greatly enlarged. The Clover-seed Midge, Cecidomyia leguminicola (C. le- gu-mi-nic'o-la), is a much more serious pest of clover. This infests both red and white clover. The larvae live in the heads of the clover and destroy the immature seed. When nil-grown they drop to the ground, where they undergo their transformations. In some parts of this country it is impossible to raise clover-seed on account of this pest. The Hessian-fly, Cecidomyia destructor (C. de-struc'tor).— s is perhaps the most serious pest infesting wheat in this ountry. The larva lives at the base of a leaf between it I the main stalk. There are two or three broods of this 'sect m the course of the year. The larvae of the fall brood DIPTERA. 447 infest the young wheat-plants near the surface of the ground. When full-grown each changes to a pupa within a brown puparium, which resembles a flax-seed. Here they remain throughout the winter. In the spring the adult gnats emerge and lay their eggs in the sheaths of leaves some dis- tance above the ground. The infested plants are so weak- ened by the larva that they produce but little if any seed. The Wheat-midge, Diplosis tritici (Di-plo'sis trit'i-ci). — This gnat is also a very serious enemy of wheat. It deposits its eggs in the opening flowers of wheat. The larvae feed on the pollen and the milky juice of the immature seeds, causing them to shrivel up and become comparatively worthless. When full-grown the larvae drop to the ground, where the transformations are undergone near the surface. The adults appear in May or June. The Resin-gnat, Diplosis resinicola (D. res-i-nic'o-la). — • This species infests the branches of various species of pine. a!a. (From the Author's Report for 1879.) We have found it throughout the Atlantic region from New York to Florida. The larvae live together in considerable numbers within a lump of resin. They derive their nourish- ment from the abraded bark of the twig; and the resin exuding from the wound completely surrounds and protects 448 THE STUDY OF INSECTS. them. The transformations are undergone within the lump of resin. After the gnats emerge the empty pupa-skins pro- ject from the lump of resin as shown at the right in Figure 526. In this figure the gnat, a single wing, and a part of the antenna of each sex are represented, all greatly enlarged. Family RHYPHID.E (Rhyph'i-dae). The False Crane-flies. The false crane-flies are so called because they resemble the Tipulidae somewhat in the venation of the wings, the FIG. 527.— Wing of Rhyfhus. three branches of vein V being preserved, and cell V, being — divided by a cross-vein (Fig. 527). They lack, % however, the V-shaped suture on the thorax »1| that is characteristic of crane-flies; and differ, •| also, in having ocelli, and in the structure of the | antennae (Fig. 528). The wings are wider than if is usual with crane-flies, and the branches of F.G. 528. lvein In separate nearer the base of the wing than in that family. The adults are mosquito-like insects with spotted wings, which often enter houses, where they are found on windows. We have also observed them in considerable numbers just at nightfall, feeding on sugar which had been placed on DIPTERA. 449 trees to attract moths. They feed on over-ripe fruit and other vegetable substances. The larvae are found in pools and in decaying vegetable matter ; they have two pairs of spiracles, one at each end of the body. The pupae are free. Only four species of false crane-flies have been found in the United States ; these belong to the genus Rhyphus (Rhy'phus). Family ORPHNEPHILID^; (Orph-ne-phiri-dae). The Solitary-midge. Only a single species of this family, Orphnephila testacea (Orph-neph'i-la tes-ta'ce-a), is known to occur in North America. This is a small fly measuring about one eighth of an inch in length, with a wing-expanse of one third inch. The antennae are short, about as long as the head, and nearly of the same structure in both sexes ; the segments of the antennas except those at the base are slender and are clothed with a few short hairs. The ocelli are wanting. The compound eyes are large and meet in front in both sexes. The wing-veins are well developed on all parts of the wing ; vein II ends in the margin of the wing before the end of the basal third ; vein III is two-branched, the first branch ending in the margin at the end of the second third of the wing and the other branch near the apex of the wing ; vein V is two-branched, the branches separating at the end of the basal third of the wing and near the cross-vein III-V ; the fork of vein VII and the cross-vein V-VII are near the end of the basal fourth of the wing. The transformations of this insect are unknown. Family BIBIONID.E (Bib i-on'i-dae). The March-flies. In these flies the body is comparatively robust, and the legs shorter and stouter than in most of the families with 450 THE STUDY OF INSECTS. thread-like antennae (Fig. 529). The abdomen, however, is much longer than wide. The antennae (Fig. 530) are shorter than the thorax, and composed of short, broad, FIG. $*<).— Bibio. FIG. 530. \ * ^^^^L/^^0 ) Q \ m *w segments. Although the an- tennae are hairy, they are not furnished with whorls of long hairs in the males, as is the case in most of the preceding families. These insects resemble the fungus-gnats in having ocelli ; but they differ from them in the shortness of the antennae and in the fact that the coxae are not greatly elongate. In this family and the following one the eyes of the males are in many cases contiguous. The venation of the wings of the typical genus is represented by Figure 531. FIG. 531.— Wing of Bibio. The adult flies are generally black and red, sometimes yellow. They are most common in early spring ; which has suggested the name March-flies ; but some occur later in the season. The larvae vary in habits ; some species feed on decay- ing vegetable matter, while others attack the roots of grow- ing plants, especially of grass. They have ten pairs of spiracles ; which is an unusually large number, as but few insects have more than nine pairs. The pupae are usually free. DIPT ERA. 45* v Family SiMULUD^E (Sim-u-li'i-dae). The Black-flies. The common name, black-flies, given to the members of this family is not distinctive, for there are many species in other families that are of this color ; but like many other names that are descriptive in form, it has come to have a specific meaning distinct from its original one. It is like the word blackberry ; some blackberries are white, and not all berries that are black are blackberries. In this family the body is short and stout (Fig. 532) ; the legs are short, and the tibiae are without spurs. The anten- nae, although composed of many seg- ments, are comparatively short, and taper towards the tip (Fig. 533) ; the segments of the- antennae are short and closely pressed together ; they are clothed with fine hairs, but do not bear whorls of long hairs. There are no ocelli. In the males the compound eyes are contiguous, and are composed of two kinds of ocelli, those of one part of the eye being much larger than FIG FJG FIG. S34-— Wing of Simulium. the others. The wings are broad, iridescent, and not clothed with hairs. The veins near the costal border are stout ; those on the other parts of the wing are very weak (Fig. 534). 452 THE STUDY OF INSECTS. The females of -many species suck blood and are well- known pests. Unlike mosquitoes and midges, the black-flies like heat and strong light. They are often seen in large numbers disporting themselves in the brightest sunshine. The larvae are aquatic ; and usually live in swiftly-flowing streams, clinging to the surface of rocks in rapids or on the brinks of falls. They sometimes occur in such large num- bers as to form a moss-like coating over the rocks. There is a disk-like sucker fringed with little hooks at the caudal end of the body by means of which the larva clings to the rocks; and just back of the head there is a fleshy proleg which ends in a similar sucker fringed with hooks (Fig. 535). By means of these two organs the larva is able to walk with a looping gait similar to that of a measuring-worm. It also has the power of spinning silk from its mouth, which it uses in locomotion. The hooks on the caudal sucker and at the end of the proleg are well adapted FIG . - Head to c^nging to a thread or to a film of silk of "larva. Spun upon the rock to which the larva is clinging. Respiration is accomplished by means of three much-branched tracheal gills which are pushed out from be- tween the last two abdominal segments. The head bears two large fan-shaped organs, which aid in procuring food. The food consists of microscopic plants and bits of tissue of larger plants. When full-grown the larva spins a boot-shaped cocoon within which the pupa state is passed (Fig- 536)- This cocoon is firmly fast- ened to the rock upon which the larva has lived or to other cocoons, for they occur in dense masses, forming a carpet- like covering on the rocks. The pupa, like the larva, breathes by tracheal gills ; but in tin's stage the tracheal gills are FlG. S36.-Lar borne by the prothorax. DIPTERA. 453 The adult fly, on emerging from the pupa-skin, rises to the surface of the water and takes flight at once. Soon after this, the eggs are laid. We have often watched the flies hovering over the brink of a fall where there was a thin sheet of swiftly-flowing water, and have seen them dart into the water and out again. At such times we have always found the surface of the rock more or less thickly coated with eggs, and have no doubt that an egg is fastened to the rock each time a fly darts into the water. The above account is based on observations made on the Innoxious Black-fly, Simulium innoxium (Si-mu'li-um in- nox'i-um), which is exceedingly common in the streams about Ithaca, N. Y. This species, fortunately, is not blood- thirsty, for, notwithstanding its great abundance in this locality, we have never known it to bite. The Southern Buffalo-gnat, Simulium pecuarum (S. pec- u-a'rum), of the Mississippi Valley is a terrible pest, which causes the death of many mules and other domestic animals. The popular name of this insect refers to a fancied resem- blance in the shape of the insect when viewed from one side to that of a buffalo. The Turkey-gnat, Simulium meridionale (S. me-rid-i-o- na'le), closely resembles the preceding in habits, infesting all kinds of domestic animals ; but as it appears at the time that turkeys are setting and causes great injury to this fowl, it is commonly known as the Turkey-gnat. The Adirondack Black-fly, Simulium molestum (S. mo- les'tum), is a scourge in the mountains of the Northeastern States. Family TABANID^: (Ta-ban'i-dae). The Horse-flies. The horse-flies are well-known pests of stock, and are often extremely annoying to man. They appear in sum- mer, are common in woods, and are most abundant in the hottest weather. 454 THE STUDY OF INSECTS. In this family the third segment of the antenna is ringed (Figs. 537, 538) and is never furnished with a distinct style or bristle. The wing-veins (Fig. 539) are evenly distributed over the wing, as the branches of vein III are not crowded together as in the follow- ing family ; the costal vein extends completely around the wing ; the alulets are large. The flight of these flies is very powerful ; they are able to outstrip the swiftest horse. The males feed on the nectar of flowers and on Antenna'of sweet sap. The mouth-parts of the Chrysops. r * female are fitted for piercing the skin and sucking the blood of men and quadrupeds; the •VIIj + IX' FIG. 539.— Wing of Tabanus. females, however, also feed on the sweets of plants when they cannot obtain blood. The larvae are carnivorous ; many live in the earth ; others live in water. They feed on various small animals ; some upon snails, others upon the larvae of insects. In most cases they have a single pair of spiracles, which is situated at the hind end of the body; some have a pair of spiracles at each end of the body. The pupa is not enclosed in the skin of the larva. D1PTERA. 455 The larger species, as well as some of moderate size, belong to the genus Tabanus (Ta-ba'nus), of which nearly one hundred American spe- cies are known. One of the most common of these is the Mourning Horse-fly, Tabanus atratus (T. a-tra'tus). This insect is of an uniform black color throughout, except that the body may have a bluish tinge (Fig. 540). To the genus Chrysops (Chry'sops) belong the smaller and more common horse-flies with banded wings (Fig. 541). Nearly fifty North American species of this genus have been described. Family STRATIOMYIID/E (Strat-i-o-my-i'i-doe). The Soldier-flies. The soldier-flies are so called on account of the bright- colored stripes, with which some of the species are marked. In the more typical mem- bers of this family the abdo- men is broad and greatly *\ I I flattened (Fig. 542), and the |f \ wings when at rest lie parallel 'tf JttL uP°n eacn other over the ab- vi 99 domen. But in some genera « V i - the abdomen is narrow and considerably elongate. The antennae vary greatly in form ; in some genera the third segment is long and con- sists of several quite distinct rings (Fig. 543) ; in others it is short with but few indistinctly-separated rings and with a bristle (Fig. 544), as in the true true short-horned flies. The most distinctive characteristic is the peculiar vena FIG 543' 456 THE STUD Y OF INSECTS. tion of the wings (Fig. 545). The branches of vein III are crowded together near the costal border of the wing ; and FIG. 546 — Puparium of Odon- FlG. 545. — Wing of Stratiomyia. the first cell V, is unusually short and broad ; the branches of Vein V and vein VII, are comparatively weak. These flies are found on flowers and leaves, especially in the vicinity of water and in bogs and marshes. The larvae live in water, earth or decaying wood. Some are carnivorous, others feed on tomyia. decaying vegetable matter. They have six or seven pairs of spiracles ; the pupa state is passed within the skin of the larva (Fig. 546). Family LEPTID^: (Lep'ti-dae). The Snipe-flies. These trim-appearing flies have rather long legs, a cone- shaped abdomen tapering towards the hind end (Fig. 547), and sometimes a downward-projecting proboscis, which with the form of the body and legs has sug- gested the name snipe-flies. Some members of the family, however, are remarkable for their re- semblance to certain Ichneumon-flies, the abdo- men being long and somewhat compressed. The body is naked or hairy, but it is not clothed with strong bristles. Frequently the hairy covering, though short, is very dense and is of strongly-contrasting colors. Three ocelli are present. The antennae vary greatly in form ; D1PTERA. 457 genera the third segment consists of several subseg- ments, which may be quite distinct (Fig. 548) ; in others the antennae are only three-jointed, and the third segment bears a style or bristle (Fig. 549). The proboscis is usually short, only a few members of the family having it long like the bill of a snipe. The wings are broad, and when at rest are held half open. The empodia are pulvilliform ; that is, FIG. 548. — Antenna of Xylo- FIG. 549. — Antenna FIG. 550. phagus and, /, palpus. of Chrysopila. there are three, nearly equal, membranous pads beneath the tarsal claws (Fig. 550). Although the form of the antennae in certain genera closely resembles that characteristic of the long-horned flies (Nematocera), the form of the palpus even in these cases (Fig. 548, p) is that characteristic of the short-horned flies (Brachycera), being only two-jointed and not pendulous. The venation of the wings is comparatively generalized (Figs. 551, 552), each of the principal veins usually extend- ing distinct from the others; but in some veins VII, and IX coalesce at the margin of the wing (Fig, 552). Vein III is four-branched ; the branches of vein V are connected with adjacent veins only by cross-veins ; and cell V, is divided by a cross-vein. The flies are predaceous. They may be found about low bushes and on tall grass. They are somewhat sluggish, and, therefore, easily caught. The larvae also are predaceous. Some live in earth, 458 THE STUDY OF INSECTS. decaying wood, or dry sand ; others live in moss or in water. They have either two pairs of spiracles, one at each end of FIG. 551.— Wing of Leptis. the body, or are furnished with tracheal gills. The last segment of the body has a transverse cleft, both above and FIG. 552.— Wing of Xylophagus. below, which is furnished above with two processes. The pupae are free. The family is of moderate size-; about seventy North American species have been described. Family ACROCERID^: (Ac-ro-cer'i-dae). The Small-headed Flies. These flies are easily recognized by the unusually small head, the large humpbacked thorax, the in- flated abdomen, and the very large alulets (Fig. 553). FIG. ^.-Ptero- The liead is composed almost entirely of dontia miseiia. eves> an(j jn some genera is minute. The DIPT ERA. 459 eyes are contiguous in both sexes. The antennae are two- or three-jointed, and are furnished with a style or bristle in some genera, in others not. The venation of the wings varies greatly in the different genera. We are unable, there- fore, to point out distinctive features drawn from these organs. The figure given (Fig. 554) represents a single genus rather than the family. Vlh + IX FIG. 554. — Wing of Eulonchus The flies are generally slow and feeble in their move- ments. In some species that feed upon flowers the pro- boscis is very long, sometimes exceeding the body in length. Other species take no nourishment in the adult state, and have no proboscis. The empodia are pulvilliform. " The larvae are apparently chiefly parasitic, and in the few species in which they have been observed are parasitic on spiders or their cocoons, in the former cases the young larvae living within the abdomen." (Williston.) Family NEMISTRINID^: (Nem-is-trin'i-dae). The Tangle-veined Flies. The members of this family are of medium size ; some of them resemble horse-flies, and others bee-flies. They can be recognized by the peculiar venation of the wings, there being an unusual amount of anastomosing of the veins (Fig. 555), which gives the wings a very characteristic appearance. 46o THE STUDY OF INSECTS. The antennae are small and short ; the third segment is simple and furnished with a slender, jointed, terminal style. The proboscis is usually long, sometimes very long, and YJ + vn, FIG. 555. — Wing of RhyncJiocephalus sackeni. fitted for sucking nectar from flowers. Only four North American species have been described ; and these are all rare. Family AsiLiD^E (A-sil'i-dae). The Robber-flies. These are mostly large flies, and some of the.m are very large. The body is usually elongate, with a very long, slender abdomen (Fig. 556); but some species are quite stout, resembling bumblebees jn form. This resemblance is often increased by a d«nse clothing of black and yellow hairs. In this and the following family the vertex of the head FIG. 556. — Erax apical is destroying a cotton-worm. (From the Au- thor's Report for 1879.) FIG. 557.— Head of robber-fly. FIG. 558. is hollowed out between the eyes (Fig. 557). In this family the proboscis is pointed and does not bear fleshy lips at the DIPTERA, 461 tip. The antennae project forward in a prominent manner. They are three-jointed, and with or without a terminal style. The style when present sometimes appears like one or two additional segments (Fig. 558). Vein III4 (Fig. 559) does not curve forward toward the costal margin of the wing as in the following family. Cell V3 is present, but is usually closed by the coalescence of the -VU.+DC FIG. 559.— Wing of Erax. tips of veins Vs and VII,. The tips of veins VII, and IX may or may not coalesce for a short distance. The robber- flies are extremely predaceous. They not only destroy other flies, but powerful insects, as bumblebees, tiger-beetles, and dragon-flies, fall prey to them ; they will also feed upon larvae. They are common in open fields and are as apt to alight on the ground as on elevated objects. The larvae live chiefly in the ground or in decaying wood, where they prey upon the larvae of beetles ; some, however, are supposed to feed upon the roots of plants. The pupae are free. The family includes a large number of genera and species. Family MIDAID.E (Mi-da'i-dae). The Midas-flics. The Midas-flies rival the robber-flies in size, and quite closely resemble them in appearance. As in that family, the vertex of the head is hollowed out between the 462 THE STUDY OF INSECTS. eyes ; but these flies can be distinguished by the form of the proboscis, which bears a pair of fleshy lobes at the tip, by the form of the antennae, which are long and clubbed at the tip (Fig. 560),. and by the peculiar venation of the wings (Fig. 561), vein V, ter- minating at or before the apex of the wing, and the branches of vein III coalescing near the apex of the wing in an unusual way. FIG. S6o. The adult flies are predaceous. The family is a small one ; but a large proportion of the species occur on this continent. YH* la-l-IX FIG. 561.— Wing of Midas. Family APIOCERID^ (A-pi-o-cer'i-dae). The Apiocerids (A-pi-oc* e-rids). This family includes only a small number of species, Vj + VII,. FIG. 562.— Wing of Afiocera. (After Williston.) which are rare and occur in the far West. They are rather large and elongate, and are found upon flowers. DIPTERA. 463 The head is not hollowed out between the eyes ; the ocelli are present ; the antennae are furnished with a short, simple style. Vein III is usually four-branched, but some- times it is only three-branched ; all of the branches of vein III end before the apex of the wing (Fig. 562) ; cell V3 is present, but closed by the coalescence of veins Vs and VII, at the margin of the wing ; and cell V, is divided by a cross- vein. The empodia are wanting. Family BOMBYLIID^E (Bom-by-li'i-dae). The Bee-flies. These flies are mostly of medium size, some are small, others are rather large. In some the body is short and broad and densely clothed with long, delicate hair (Fig. 563). Other species resemble the horse-flies somewhat in appearance, especially in the dark color or markings of the wings ; but FlG- ^--Bombyiius. these can be distinguished from the horse-flies by the form of the antennae and the venation of the wings. The antennae are usually short ; they are three-jointed ; the third segment is not ringed ; the style is sometimes present and sometimes wanting. The ocelli are present. The proboscis is sometimes very long and slender, and sometimes short and furnished with fleshy lips at the ex- tremity. Vein III of the wings (Fig. 564) is four-branched ; cell III3 is sometimes divided by a cross-vein ; cell V3 is obliter- ated by the coalescence of veins V8 and VII, ; in a few genera cell V, is also obliterated by the coalescence of veins V, and Va ; cell VIII is narrowly open, or is closed at or near the border of the wing. The alulets are small or of moderate size. The adult flies feed on nectar, and are found hovering over blossoms, or resting on sunny paths, sticks or stones; they rarely alight on leaves. THE STUDY OF INSECTS. The larvae are parasitic, infesting hymenopterous and lepidopterous larvae and pupae and the egg-sacs of Orthop- tera, The pupae are free. FIG. 564. — Wing of Pa.nta.rbes capita. The family is a large one, including many genera and species. Family THEREVID^: (The-rev'i-dae). The Stiletto-flies. With the flies of this family the head is transverse, being nearly as wide as the thorax ; and the abdomen is long and tapering, suggesting the name stiletto-flies. These flies are small or of medium size ; they are hairy or bristly. The antennae are three-jointed ; the third segment is simple, and usually bears a terminal style ; but this is sometimes want- ing. Three ocelli are present. The legs are slender and bristly; the empodia are wanting. Vein III of the wings (Fig. 565) is four-branched, and the last branch (vein II I5) terminates beyond the apex of the wing ; the branches of vein V are all separate ; cell VIII is closed near the border of the wing; the 2d cell III and cell V are long. The adult flies are predaceous ; and conceal themselves among the leaves of low bushes or settle on the ground in sandy spots, waiting for other insects upon which they prey. The larvae are long and slender, and the body is appar- ently composed of nineteen segments. They are found in DIPT ERA. 465 earth, fungi, and decaying wood. They feed on decaying animal and vegetable matter and are said to be predaceous also. The pupae are free. Vlh+IX VII, FIG. 565. — Wing of Therev*. The family is a comparatively small one, including but few genera and species. Family SCENOPINID^E (Scen-o-pin'i-dae). The Window-flies. The window-flies are so-called because the best-known species are found almost exclusively on windows ; but the conclusion that these are the most common flies found on windows should not be drawn from this name ; for such is not the case. These flies are of medium size, our most common species measuring one-fourth inch in length. They are usually black, and are not clothed with bristles. The thorax is prominent, and the abdomen is flattened and somewhat bent down, so that the body when viewed from the side presents a humpbacked appearance (Fig. 566). When at rest, the wings lie parallel, one over the other, on the abdomen ; when in this position they are very inconspicuous. There are three ocelli. The antennae are three-jointed'; the first and second segments are short, the third is long and bears neither a style nor a bristle (Fig. 567). FIG. 566. FIG. 567. Scenopinus. 466 THE STUD Y OF INSECTS. The venation of the wings is represented by Figure 568. Vein III is four-branched ; cells V, and V, are both obliter- ated by the coalescence of the veins that bound them ; cell VIII is closed at a considerable distance before the margin ; and the 2d cell III is much longer than cell V. The larvae, which are sometimes found in dwellings FIG. 568.— Wing of Scenopinus. under carpets or in furniture, are very slender, and are re- markable for the apparently large number of the segments of the body, each of the abdominal segments except the last being divided by a strong constriction. They are also found in decaying wood, and are supposed to be carnivorous. The family is a very small one. The most common species is Scenopinus fenestralis (Sce-nop'i-nus fen-es-tra'lis). Family EMPIDID^E (Em-pid'i-dae). The Dance-flies. The dance-flies are of medium or small size ; they are often seen in swarms under trees or near shrubs and about brooks, dancing and hunting. The family is a rather diffi- cult one to characterize owing to great variations in the form of the antennae and in the venation of the wings. The branches of vein VII coalesce with the adjacent veins (VII, with V8 and VII2 with IX) from the margin of the wing towards the base for a considerable distance (Fig. 569). In most of the genera this coalescence is carried so far that the free parts of the branches of vein VII appear DIPTERA. 467 like cross-veins. The only other families of the suborder Orthorrhapha in which this occurs are the two following ; and the venation of the wings in each of these is very differ- ent from that of the Empididae. The antennae are three-jointed ; the first and second FIG. 569.— Wing of Rhamphomyia. segments are often very small, and then appear like a single segment ; the third segment may or may not bear a style or bristle. The mouth-parts are in many cases long, and ex- tend at right angles to the body or are bent back upon the breast. These flies are predaceous, like the robber-flies ; but they also frequent flowers. The larvae live in decaying vegetable matter, but are probably carnivorous. The pupae are free. The family is a large one, containing many genera and species. Family DOLICHOPODID^: (Dol-i-cho-pod'i-dae). The Long-legged Flies. These flies are of small or medium size and usually bright metallic green in color. The legs are much longer than is usual in the families belonging to the series of short-horned flies (Fig. 570). This suggested the name Do- lichopus (Do-lich'o-pus), which means long- footed, for the typical genus; and from this FlG the family name is derived. It should be _/w/vAo- 468 THE STUD Y OF INSECTS. remembered, however, that these flies are long-legged in comparison with the allied families, and not in comparison with crane-flies and midges. The members of this family are easily distinguished as such by the peculiar venation of the wings, the most char- acteristic features of which are the following (Fig. 571): cells V and ist V, are not separated by a vein, the basal part of vein V3 being undeveloped ; veins III.2+3 and III4+B separate near the base of the wing, and the two veins form FIG. 571.— Wing of Psihphu* ciliatus. at the point of separation a more or less knot-shaped swell- ing; the cross-vein III-V is at or close by this swelling, so that cell III is very short. A somewhat similar venation occurs in some of the Muscidae ; but there the knot-shaped swelling on vein III is often wanting, and the cross-vein III-V is usually more remote from the base of the wing; and too the flies belonging to the Muscidae possess the suture above the antennae characteristic of the suborder Cy- clorrhapha. The members of this family have three ocelli ; the an- tennae are three-jointed ; the second segment of the antenna is sometimes rudimentary ; and the third segment bears a two-jointed arista. The adults are predaceous and hunt for smaller flies and DIPTERA. 469 other soft-bodied insects. They are usually found in damp places, covered with rank vegetation. Some species occur chiefly on the leaves of aquatic plants, and about dams and waterfalls ; and some are able to run over the surface of water. Others occur in dry places. The larvae live in earth or decomposing vegetable matter. They are long, slender, and cylindrical, and have two pairs of spiracles, one at each end of the body. In most cases the pupae are free ; but some form cocoons. The thorax of the pupa bears a pair of long breathing-tubes. The family is a large one ; more than two hundred North American species have been described already. Family LONCHOPTERID.E (Lon-chop-ter'i-dae). The Spear-winged Flies. These are minute flies, which measure from one twelfth to one sixth of an inch in length, and are usually brownish or yellowish. When at rest the wings are folded flat, one over the other, on the abdomen. The apex of the wing is pointed ; and the wing as a whole is shaped somewhat like the head of a spear. This suggested the family name. The venation of the wings is very characteristic, and is sufficient to distinguish these flies from all others. The Vila Vj •«• VII i FIG. 572.— Wing of Lonchoptera. cross-veins III-V and V-VII are oblique, and near the base of the wing (Fig. 572)- Vein VII, is very short, and extends towards the base of the wing. In the females vein 470 THE STUD Y OF INSECTS. VII, coalesces with vein V3 , as shown in the figure ; but in the males the tip of vein YII, is free. The posterior lobe is wanting. Three ocelli are present. The antennae are three-jointed ; the third segment is globular, and bears a three-jointed style. These flies are common from spring till autumn, in damp grassy places. They frequent the shores of shady brooks, where the atmosphere is moist. But little is known as yet about their habits and tranformations. In the shape of the wings, the absence of cross-veins, except at the base of the wing, and the great reduction of the anal area of the wing the flies closely resemble the Psy- chodidae. Suborder CYCLORRHAPHA (Cy-clor'rha-pha). The Circular-seamed Flies. To this suborder belong those families of flies in which the pupa escapes from the larval skin through a round opening made by pushing off the head- end of it (Fig. 573). The pupa is always enclosed in a puparium. The adult flies possess a frontal lunule (see footnote page 461), and except in the pupGa'num~of ^rst ^our families a frontal suture, through which a Muscid. tjie ptilinum is pushed out, when the adult is about to emerge from the puparium (see page 419). Family SYRPHID^: (Syr'phi-dae). The Syrphus-flies. The family Syrphidae includes many of our common flies ; but the different species vary so much in form that no general description of their appearance can be given. Many of them mimic hymenopterous insects ; thus some species resemble bumblebees, others the honey-bee, and still others wasps ; while some present but little resemblance to any of these. DIPTERA. 471 The most distinctive characteristic of the family is the presence of a thickening of the membrane of the wing, which appears like a longitudinal vein between veins III and V. This is termed the spurious vein, and is lacking in only a few members of the family ; it is represented in Figure 574 by a FIG. 574.— Wing of Eristalis. band of stippling. Cell III6 is closed ; and the 2d cell III and cell V are large, The antennae are three-jointed ; the third segment usually bears a dorsal bristle, but sometimes it is furnished with a thickened style. The face is not furnished with longitudinal furrows to receive the antennae as in the Muscidae. The frontal lunule is present, but the frontal suture is wanting. The adults frequent flowers an.d feed upon honey and pollen. Some fly with a loud humming sound like that of a bee ; others hover motionless except as to their wings for a time, and then dart away suddenly for a short distance, and then resume their hovering. The larvae vary greatly in form and habits. Some prey upon plant-lice, and are often found in the midst of colonies of these insects ; others feed on decaying vegetable matter, and live in rotten wood, in mud, and in water. Some are found in the nests of ants ; and some in the nests of bum- blebees and of wasps. Among the common representatives of this family there is one that so closely resembles a male honey-bee as to be § 472 THE STUDY OF INSECTS. often mistaken for it. This is the Drone-fly, Eristalis tenax (E-ris'ta-lis te'nax). It is common about flowers. The larva lives in foul water, where it feeds on decaying vegeta- ble matter ; it is of the form known as " rat-tailed," which is described below. The larvae of the genus Volucella (Vol-u-cel'la) are pre- daceous, living in the nests of bumblebees and of wasps (Vespa), and feeding upon their larvae. Some of the species in the adult state very closely re- semble bumblebees. The larvae of the genus Micro- dkw(Mic'ro-don) are hemispherical, FIG. 575. — Microdon^ adult and x / larva- slug -like creatures (Fig. 575), which resemble mollusks more than ordinary maggots ; they are common in ants' nests. The larvae of several species that live in water as well as some that live in rotten wood are known as rat-tailed mag- gots on account of a long, tail-like appendage, with which the hind end of the body is furnished. This is a tube, like that of a diver, which enables the insect to obtain air when its body is submerged beneath several inches of water or de- caying matter. This tube being telescopic can be lengthened or shortened as the insect may need it; and at its tip there is a rosette of hairs, which, floating on the surface of the water, keeps the tip from being submerged. The larva has on the ventral side of its body several pairs of tubercles armed with spines, which serve as prolegs. Among the more common members of this family are the yellow-banded species belonging to the genus Syrphus (Syr'phus) (Fig. 576). The larvae of these live in colonies of Aphids, and do much good by destroying these pests. This family is a very large one ; nearly or FIG. 576. — Syr- quite two thousand species being known. In /***• his monograph of the species of America north of Mexico, DIPTERA. 473 Professor Williston describes about three hundred species from this region.* Family PlPUNCULID^; (Pip-un-cu'li-dae). The Big-eyed Flies. This family is represented in the United States by a single genus, Pipunculus (Pi-pun'cu-lus). These are small flies, with very large heads composed almost en- tirely of eyes (Fig. 577). The head is nearly spherical, and broader than the thorax. The abdomen is somewhat elongate with the sides nearly parallel. The body is thinly clothed with hair or nearly naked. The wings are much longer than the abdomen, and when at rest they lie parallel to each other upon it. (Fig. 578) closely resembles that of some of the Conopidae. Vein III is three-branched. The last branch of Vein III and FIG. 577.- Pipun- The venation FIG. 578.— Wing of Pifunculus. the first branch of vein V approach each other at their tips. Vein Vs coalesces with vein VII, for nearly its entire length. Veins VII, and IX coalesce at their tips. Cells III and V are long. The flies hover in shady places. They are sometimes found on flowers, and may be swept from low plants ; our most common species measure about one eighth of an inch in length, not including the wings. The larvae so far as known are parasitic upon bugs. * Bulletin of the U. S. National Museum, No. 31. 474 THE STUD Y OF INSECTS. Family PLATYPEZID.E (Plat-y-pez'i-dae). The Flat-footed Flies. These flies resemble the House-fly somewhat in appear- ance but are very much smaller. They hover in the air in shady places, and alight frequently on the leaves of low plants, where they run about in circles with great rapidity. The head is hemispherical or spherical, and as broad as or broader than the thorax. The antennae are three-jointed, with a terminal bristle. The legs are short and stout, and the tarsi of the hinder Pa'r are °ften very broad and flat (Fig. 579)- The wings are rather large, and when at rest lie parallel upon the abdo- men ; the axillary excision is prominent, but the posterior lobe of the wing is small (Fig. 580) ; the alulets are minute. Vein III of the wings is three- branched ; veins V, and Vs either coalesce FIG. 579.— Leg of puty- throughout or separate near the margin /«««, forked hairs of g . ~ «1T • • ,- -J , , leg greatly enlarged. of the Wing. Cell V, IS Sometimes divided FIG. 580 —Wing of Platypeza. by a cross-vein, and sometimes not. Cells 2d III, V, and VIII are short. This family includes but few species, and these are usually rare. The larvae live in rotten mushrooms. DIPTERA. 475 Family PHORID^E (Phor'i-dae). The Humpbacked Flies, These are minute, dark-colored, usually black flies, which can easily be recognized by their humpbacked form and the peculiar venation of the wings. Certain species are often found running about rapidly on windows, others on fallen leaves. Sometimes they are seen in swarms dancing up and down in the air. The head is small ; the thorax large and humped ; and the abdomen rather short. The antennae are apparently IX FIG. 581.— Wing of Pkora.. one- or two-jointed, the last segment with either a dorsal or a terminal bristle. The coxae are long ; the femora, espe- cially of the hind legs, which are rather long, are widened and flattened. The wings (Fig. 581) are large, and are fur- nished with two strong veins near the costal border, which extend but a short distance beyond the middle of the wing. From these strong veins from three to five weak ones extend across the wing. The larvae feed on decaying vegetable matter, dead insects, snails, etc., and some are believed to be parasitic upon other insects. THE STUDY OF INSECTS. Family CONOPiD/£ (Co-nop'i-dae). The Thick-head Flies. With the members of this family the head is large, being broader than the thorax. The body is more or less elon- gate ; sometimes the abdomen has a long, slender pedicel like that of certain wasps. The body may be naked or thinly clothed with fine hair, but it is rarely bristly. The ocelli may be either present or absent. The an- tennae are prominent, and project forward ; they are three- jointed ; and the third segment bears either a dorsal bristle Vlh+TX FIG. 582.— Wing- of Conors ajfjUnis. or a terminal style. Vein III of the wings (Fig. 582) is only three-branched. The last branch of vein III and the first branch of vein V end near together or coalesce at their tips. Cell V, is divided by a cross-vein. Vein V3 coalesces with vein VII, for nearly its entire length. Veins VII, and IX coalesce at their tips, and sometimes for nearly the entire length of vein VII,. The adult flies are found on flowers. In some genera the abdomen is long, with a slender, wasp-like pedicel (Fig. 583). In others the abdomen is of the more usual form> The jarvag are parasjt jC) chiefly upon bumblebees and wasps, but some species infest locusts. DJPTERA. 477 Family CESTRID^; (CEs'tri-dae). The Bot-flies. This family includes flies that are large or of medium size ; most of the species resemble bees in appearance ; some, the honey-bee ; others, bumblebees. In the vena- tion of the wings they closely resemble the Muscidae ; but the wings are usually furnished with fine transverse wrinkles. They are most easily distinguished from the Muscidae by the small size of the opening of the mouth and the rudi- mentary condition of the mouth-parts, the proboscis being rudimentary and the palpi usually wanting. The head is large, with the face broad. The antennae are small, three-jointed, more or less concealed in a suban- tennal cavity or grooves ; the last segment bears a dorsal bristle. Vein III of the wings is three-branched. Cell III6 is broadly open (Fig. 584), or is narrowed at the margin of Vj + VII, FIG. 584.— Wing of Gastrcphilus. the wing, or closed. The alulets are usually large, conceal- ing the halteres ; but sometimes they are small. The larvae are parasitic upon mammals. The best known species are the following : The Horse Bot-fly, Gastrophilus equi (Gas-troph'i-lus e'qui). — The adult fly closely resembles the honey-bee in 478 THE STUDY OF INSECTS. form except that the female (Fig. 585) has the end of the abdomen elongate and bent forward under the body. It is most often seen flying about horses, which have an instinctive fear of it. The eggs are attached to the hair, chiefly on the legs and shoulders of the horse. The larvae are licked off by the horse and swallowed with its food. FIG. 585. "When the larvae reach the stomach they fasten themselves to the inner coat of it, and remain there until full-grown. Then they pass from the animal with the dung, and crawl into some protected place, where they transform within a puparium. The Oxwarble, Hypoderma lineata (Hyp-o-der'ma lin- e-a'ta). — The larva of this species is the common pest that lives in the backs of cattle just beneath the skin. The adult lays its eggs on the backs of cattle ; and it has been supposed that the young larvae penetrate the skin, thus reaching the place where they are commonly found. But Dr. Cooper Curtice has recently shown that the larvae are licked off from the back by the cattle and swallowed. He found the larvae in large numbers in the walls of the oesophagus in November; later, about Christmas-time, they appeared sud- denly, and in large numbers under the skin of the back. The course of their migration from the oesophagus to the skin has not yet been traced. The greater part of the growth of the larva is made within the tumor beneath the skin. When full-grown it passes out through a hole in the skin and undergoes its transformations on the ground. Dr. Curtice has also shown that the most common oxwarble of this country is Hypoderma lineata and not Hypoderma bovis, as has been supposed. The Sheep Bot-fly, CEstrus ovis (GEs'trus o'vis). — The eggs of this species are laid in the nostrils of sheep. The larvae pass up into the frontal sinuses and into the horns when they are present. Here they feed upon the mucus. They are very injurious to sheep, causing vertigo or the DIPTERA. 479 disease known as " staggers." When full-grown they pass out through the nostrils and undergo their transformations beneath the surface of the ground. Other species infest rabbits, squirrels, deer, and reindeer. One that lives beneath the skin of the neck of rabbits is very common in the South. Family MUSCID.E (Mus'ci-dae). The Muscids (Mus'cids). The form of the more typical members of this family is well shown by the common House-fly. But the family is a very large one and includes species that differ greatly in form. These differences are so great and so varied that some writers divide the family into nearly thirty families. It seems to us, however, to be better to consider these divisions of subfamily value. The following characters are presented by the family as a whole. The antennae (Fig. 586) are three-jointed ; the third seg- ment bears a dorsal bristle. The frontal suture is present (Fig. 587). The proboscis is always present. Vein II of the wings may be present or absent ; vein III is three- branched ; cells V, and V, are wanting ; the branches of vein VII coalesce with the adjacent veins (VII, with Vs, and VII, with IX) for nearly their entire length. The pulvilli are present, and the empodia are never pulvilliform. As this family includes more than one third of all the known Diptera, it usually happens that a large proportion of the flies in a collection belong to it. It seems necessary, therefore, to indicate some of the principal divisions of the FIG. 586. FIG. 587. 48o THE STUDY OF INSECTS. family. This first of these is into two groups of subfamilies, and is based upon the size of the alulets. The division is not a satisfactory one ; and it is only given here because it is commonly employed by writers on the Diptera, and a more definite one has not yet been discovered. A. The alulets large ; face with a depression or vertical grooves beneath the antennae; cell Hie closed or 'narrowly open, except in the Anthomyiinae, where it is widely open. p. 480. CALYPTRATE MUSCIDJE. A A. The alulets small or wanting; form of face varied; cell III5 usually widely open. p. 484 ACALYPTRATE MUSCID^E. I. CALYPTRATE MUSCID^E (Ca-lyp'trate). To this division belong our most familiar representatives ot the family, of which the House-fly and the flesh-flies are good illustrations. As a rule cell III5 of the wings is closed or narrowly open (Fig. 588) ; but in the last subfamily this FIG. 588.— Wing of Mu cell is widely open (Fig. 589). Five subfamilies are classed here ; these can be separated by the following table, which is based on one given by Professor Williston. A. Cell IIIS of the wings closed or more or less narrowed at the margin of the wing (Fig. 588). B. Antennal bristle wholly bare. p. 481 ............. BB. Antennal bristle distinctly pubescent or plumose. DIPTERA. 481 C. Antennal bristle bare near the tip. p. 482. .SARCOPHAGIN^E, CC. Antennal bristle plumose or pubescent to the tip. D. Dorsum of abdomen bristly ; legs usually elongate, p. 482. DEXIINyE. DD. Abdomen not bristly, except sometimes somewhat so near the tip. p. 482 ............................ MUSCIN.E. AA. Cell III6 widely open, not narrowed at the margin of the wing (Fig. 589). p. 483 ............................... ANTHOMYIINJE. FIG. 589.— Wing of Lispe. Subfamily TACHININ.E (Tach-i-ni'nae). The Tachina-flies (Ta-chi'na). The Tachina-flies are often found about flowers and rank vegetation. They are usually short, stout, and bristly, and can be distinguished from the three following subfamilies by the bristle of the antennae being wholly bare. The larvae are parasitic, chiefly within caterpillars, and play an ex- ceedingly important part in check- ing the increase of noxious insects. The female fastens her eggs to the n,rtuvm i • t «.*».-f»J11if /TTJrr r/-u~>\ • upon fore part of an army-worm. Skin Of a Caterpillar (rig. 59°); (From the author's Report for when the larvae hatch they bore l879-) their way into their host and live there till they are full- grown. 482 THE STUDY OF INSECTS. Subfamily SARCOPHAGUS (Sar-coph-a-gi'nae). The Flesh-flies. These flies resemble those of the preceding subfamily in general appearance, but differ in having the bristle of the antenna plumose or hairy at the base ; the outer end of the bristle is bare. They are called flesh-flies because many of them lay their eggs on the bodies of dead animals, resem- bling in habits the Blow-fly, which belongs to the sub- family Muscinae. The larvae of other species live in dung, in decaying vegetable matter, and in fruits. Subfamily DEXIIN.E (Dex-i-i'nae). The Nimble- flies. In this subfamily the bristle of the antenna is plumose or bristly to the tip, and the dorsum of the abdomen is bristly. The legs are usually long. These flies are much less common than the members of the allied subfamilies ; the larvae of some of the species, at least, are parasitic. Subfamily MUSCINAE (Mus-ci'nae). The Typical Muscids (Mus1 cids}. With these flies, as in the preceding subfamily, the bris- tle of the antenna is pubescent or plumose to the tip; but the abdomen is not bristly except near the tip. Here be- long many of the best-known members of the Muscidae; among the more important ones are the following : — The House-fly, Musca domestica (Mus'ca do-mes'ti-ca). — This is the most familiar representative of the order Diptera, as it abounds in our dwellings. It lays its eggs in horse- manure, a single female laying from one hundred and twenty to one hundred and sixty eggs ; the larvae become full- grown in from five to seven days, having molted twice ; the pupa state lasts from five to seven days. The Stable-fly, Stomoxys calcitrans (Sto-mox'ys cal'ci- trans). — This species resemble the House-fly in appearance ; DIPTERA. 483 but it has its mouth fitted for piercing and for sucking blood. It annoys cattle greatly ; and before storms and in the autumn it enters our dwellings and attacks us. The larvae live in fresh horse-manure. The Horn-fly, Hcematobia serrata (Haem-a-to'bi-a ser- ra'ta). — This is an exceedingly annoying pest of horned cattle, which has spread over the United States in recent years. It resembles the House-fly in appearance ; but is less than half as large. These flies cluster in great numbers around the base of the horns; they also settle upon the back. The larvae live in fresh cow-manure. The Screw-worm Fly, Campsomyia macellaria (Camp-so- my'i-a mac-el-la'ri-a), is a bright metallic-green fly, with four black stripes on the upper part of the thorax ; it measures about one third of an inch in length. This terrible pest resembles the flesh-flies in habits, and it deposits its eggs in wounds, sores, and the nostrils and ears of men and cattle. The larvae living in these situations often cause serious sickness, and sometimes even death. The Blow-fly, Calliphora vomitoria (Cal-liph'o-ra vom-i- to'ri-a), is larger than the House-fly, and black in color, with a steel-blue abdomen. It flies with a loud buzzing noise, and lays its eggs upon meat, cheese, and other provisions. The eggs hatch in about twenty-four hours, and the larvae become full-grown in a few days. Subfamily ANTHOMYIIN^E (An-tho-my-i-i'nae). The Anthomyiids (An-tho-my'i-ids). The members of this subfamily differ from other Ca- lyptrate Muscidae in having cell III5 widely open, vein Vl+, nearly straight (Fig. 589), and not bent in its outer part towards the tip of vein III4+, , as in the preceding subfam- ilies. In fact, the type of venation is the same as that which is characteristic of nearly all of the Acalyptrate Muscidae ; and as the alulets are quite small in some of the Anthomyiids, it is difficult for the beginner to recognize all 484 THE STUDY OF INSECTS. members of this family as such. It is to be hoped that other characters than those we now know for separating the Calyptrate Muscidae from the Acalyptrate Muscidae will soon be discovered. The Anthomyiids are very common flies. They are found on leaves and flowers, and are also often found on win- dows in our dwellings. The larvae of most species live in decaying vegetable matter, a few are parasitic on other in- sects, and some attack growing plants. Among the latter are certain well-known pests infesting garden crops. The more important of these are the following: — The Cabbage-root Maggot, Phorbia brassier (Phor'bi-a bras'si-cae). — This insect in its larval state feeds on the roots of cabbage, radish, turnip, and cauliflower; it also attacks the roots of various weeds belonging to the same family of plants. It is one of the most serious pests that gardeners have to contend with. The Onion-fly, Phorbia ceparum (P. ce-pa'rum). — The larva of this species is often exceedingly destructive to onions, consuming the bulb of the plant. The leaves of beet are often mined by maggots ; and it has been found that this injury is due to several species of Anthomyiids. The most common of these is Pegomyia (Peg-o-my'i-a vi-ci'na). II. ACALYPTRATE MUSCIDAE (Ac-a-lyp'trate). To this division of the Muscidae belong a very large number of common flies. These vary greatly in form, and represent a large number of distinct subfamilies. As a rule cell III& of the wings is widely open (Fig. 591), and vein II may be either present or wanting. The alulets are usually very small or rudimentary. The American species have not yet been sufficiently studied to enable us to give a table for separating the sub- families. We will merely refer, therefore, to a few of the more important species. DTPTERA. 485 The Dung-flies, Scatophaga (Sca-toph'a-ga), are rather in, FiG.591.— Wing- of Callopistria annuities. slender flies, which have the body clothed with yellowish hair, and which are com- mon, especially about fresh cow-dung. They belong to the Subfamily Cordylurince (Cor-dyl-u- ri'nae). To the subfamilies Or- talincz (Or-ta-li'nas) and Trypetince (Try-pe-ti'nae) belong many common species which have the wings beautifully marked with dark spots or bands. In the Ortalinae vein II extends to the margin of the wing in the usual way; in the Trypetinae the outer part of vein II turns suddenly towards the margin Of the wing, FiG.S92.--The Apple-maggot; T,la™; 2,Pupa- onrl of fVi<» cim<* fim<» rium; 3, adult; la, head of larva from side, ailQ at tlie Same time showing mouth-parts and cephalic spiracle; becomes much less dis- ^rahcTedof°iarvarva fron> below; IC> caudal 486 THE STUDY OF INSECTS. tinct. The two following are well-known members of the Trypetinae. The Apple-maggot, Trypeta pomonella (Try-pe'ta pom-o- nel'la.) — This maggot eats into the pulp of apples, boring tunnels in all directions through the fruit ; it attacks espe- cially the early maturing varieties. When full-grown it goes into the ground to transform. The adult is a black and white fly, with banded wings (Fig. 592). The Round Goldenrod Gall. — One of the most familiar of abnormal growths on plants is a ball-like enlargement of | the stem of goldenrod (Fig. 593). i^j^^i This is caused by a maggot, which lives within it, and which develops jOFv into a pretty fly with banded wings. ^HRI' This is Trypeta solidaginis (T. Sol-i- IP dag'i-nis). There is another gall on .-The Round Golden- the stem of goldenrod which is liable to be mistaken for this one, but which can be easily distinguished from it. It is more elongate, and is hollow. It is made by the larva of a Tineid moth, Gelechia gallcesolidaginis (Ge-le'chi-a gal-lae-sol-i-dag'i-nis) ; it may be called the Elliptical Goldenrod Gall. The Stem-eyed Fly, Sphyracephala brevicornis (Sphyr-a- ceph'a-la brev-i-cor'nis) is a very singular fly, which is found on the leaves of skunk-cabbage. On each side of the head there is horn-like process'' extending outward, upon the end of which the eye is situated. This species is the only Amer- ican representative" of its subfamily, the Diopsina (Di-op- si'nae), yet described. The Cheese-maggot, PiopJiila casei (Pi-oph'i-la ca'se-i) is the larva of a small black fly, less than half the size of the House-fly. It belongs to the small subfamily Piophilina (Pi-oph-i-li'nae), in which vein II of the wings is quite closely united with vein III. This fly lays its eggs on cheese, ham, and bacon ; the larvae live in these substances and are often serious pests. They are commonly known as "skippers " on DIPTERA. 487 account of the remarkable jumps which they can make. This is accomplished by first bringing the head and tail ends together and then suddenly straightening the body. In this way one of these maggots can jump several inches. To the genus Ephydra (Eph'y-dra) of the subfamily EphydrincB (Eph-y-dri'nae) belong several species the larvae of which live in marine or strongly alkaline waters. In the far West and in Mexico these larvae occur in the alkaline lakes in countless numbers ; and are washed ashore in such quantities that bushels of them can be collected. They are gathered by the Indians, who dry them and use them for food, which they call Koo-cha'bee. The Pomace-flies. — These are certain small yellowish flies from one-eighth to one-sixth of an inch in length, which are very common about the refuse of cider-mills, decaying fruit, and fermenting vats of grape pomace. These are the pomace-flies ; and their larvae live in the decaying fruit. A very common species is the Vine-loving Pomace-fly, Drosophila ampelophila (Dro-soph'i-la am-pe-loph'i-la) (Fig. 594). Family HlPPOBOSClD^E (Hip-po-bos'ci-dae). The Louse-flies. The louse-flies are very abnormal flies that, in the adult state, live like lice, parasitically, upon the bodies of birds and mammals. Some species are winged, others are wing- less, and still others are winged for a time and then lose their wings. The body is depressed ; the head is closely attached to the thorax, which is notched to receive it. The antennae are apparently one-jointed, with a terminal bristle or style ; they are situated in a depression near the mouth. The THE STUDY OF INSECTS. frontal suture is present. The legs are broadly separated by the sternum ; they are comparatively short and stout ; the tarsal claws are strong and are often furnished with teeth. The winged forms vary greatly in the venation of the wings. The veins near the costal border are usually strong while the others are weak. Figure 595 represents +vn, FIG. 505 Wing of Olfersia. the venation of Olfersia. In this genus veins 111,+, and III4-f-s separate near the base of the wing. In Hippobosca they separate at or beyond the middle of the wing. Even more remarkable than the parasitic life of the adult flies is the mode of reproduction of these insects. The egg is hatched within the body of the parent, the larva is nour- ished in this position till it is full-grown, and is not born till it is ready to change to a pupa. This mode of reproduction is also characteristic of the two following families, which are frequently on this account classed with this one as a division of the Diptera, termed Pupipara (Pu-pip'a-ra). The most common member of the Hippoboscidae is the Sheeptick, Melophagus ovinus (Me-loph'a-gus o-vi'nus). This is a wingless species (Fig. 596), which lives upon sheep. Hippobosca equina (Hip-po-bos'ca e-qui'na) is winged and lives on the horse. Olfersia ameri- cana (Ol-fer'si-a a-mer-i-ca'na) is also winged and is common on owls and other birds. The species of the genus Lipoptera (Li-pop'te-ra) are winged at first and live on birds ; later they migrate to quadrupeds, FIG. 596. DIPTERA. 489 where they remain, and having no further use for their wings, they lose them. Family NYCTERIBIID^E (Nyc-ter-i-bi'i-dae). The Bat-ticks. The bat-ticks are wingless parasites of bats. The body is depressed ; the head is small and folded back into a groove on the dorsum of the thorax. The compound eyes are wanting; the ocelli are present or wanting. The legs are long, and the tarsal claws of ordinary form. Although wingless the halteres are present. The mode of reproduction is similar to that of the Hippoboscidae. Family BRAULID.E (Brau'li-dae). The Bee-louse. This is a minute insect, one-sixteenth of an inch in length, which is parasitic upon the Honey- bee (Fig. 597). It is found clinging to the thorax of queens and drones. It is wing- less, and also lacks halteres. The head is large, but lacks both compound eyes and ocelli. The legs are comparatively short ; the last segment of the tarsus is furnished with a pair of comb-like appendages. Only a single species is known ; this is Braula cceca (Brau'la cae'ca). Its mode of reproduc- tion is similar to that of the Hippoboscidae. CHAPTER XX. Order SlPHONAPTERA (Siph-o-nap'te-ra). The Fleas. The members of this order are practically wingless, the wings being represented only by minute scaly plates. The mouth-parts are formed for sucking. The metamorphosis is complete. These tiny tormentors are best known to us in the adult state \ for it is only during this period that they annoy us and our household pets. The larvae and pupae are rarely observed except by students who search for them. The name of the order is from two Greek words : siphon^ a tube ; and apteros, wingless. It refers to the form of the mouth and to the wingless condition of the insects. In our more common fleas the body of the adult is oval and greatly compressed, which allows the insect to glide through the narrow spaces between the hairs of its host. The integument is smooth, quite hard, and naked, except that there are many strong spines, which are arranged with great regularity (Fig. 598), and thus af- ford good characters for distin- guishing the different species. The smoothness and firmness of the body makes it easy for the insect to escape when caught be- e Dog-flea and its ,arva.tween the fingers Qf man Qr the teeth of lower animals. Doubtless the backward projecting 49o SIPHONAPTERA. 491 spines also aid them in their efforts to escape, as every wriggle of the body pushes it forward. When once out of the clutch of an enemy, they quickly leap away. The head is broadly joined to the thorax. There are no compound eyes ; but on each side of the head there is a large ocellus, and hidden in a groove behind the ocellus is the antenna. The mouth-parts are formed for piercing and sucking ; the sucking-tube is formed of the upper lip and the two mandibles ; the maxillae are small, triangular plates and bear long, four-jointed palpi ; the labium is minute and bears a pair of terminal, three-jointed palpi. The mesothorax and metathorax each bears a pair of flat scales, which are sup- posed to be rudimentary wings. The legs are long and strong, and fitted for leaping ; the hinder pair are the larg- est and the middle pair next in size. The eggs are scattered about the floors of dwellings and in the sleeping-places of infested animals. The larvae are slender, worm-like creatures, with a distinct head and with- out legs (Fig. 598). They have biting mouth-parts, and feed upon the decaying particles of animal and vegetable matter always to be found in the dirt in which they live. When full-grown the larva spins a cocoon within which the pupa state is passed. Of the domestic animals only the dog, cat, rabbit, pigeons, and poultry have fleas. They are most common on dogs and pigeons. But the species of fleas do not appear to be so strictly limited to particular animals as are the lice and! some other parasites ; for the species that commonly infests dogs and cats will also attack man without hesitation, and in this country seems to be more troublesome to our race than the Human-flea. To rid a dog or cat of fleas it should be dusted with Persian insect powder (Pyrethrunt), and its sleeping-place thoroughly cleaned. The bedding in kennels should be of some substance which can be replaced frequently, as shav- ings or straw, and when replaced the old bedding should be 492 THE STUD Y OF INSECTS. burned, and the floors wet with kerosene emulsion or some other insecticide that will destroy the eggs and larvae. In regions where fleas abound much relief can be ob- tained by the use of rugs on the floors of dwellings instead of carpets. The frequent shaking of the rugs and cleaning of the floors will prevent the breeding of these pests within the house. As a single flea will inflict many bites, it often happens that a house will seem to be overrun by them when only a few are present. In such cases a careful search for and capture of the offenders will soon remedy the evil. We have found that in catching fleas greater success attends our efforts if the thumb and forefinger be wet before seizing the flea, and the insect be placed in a dish of water before we attempt to destroy it. Otherwise the insect is apt to escape while we are trying to destroy it. People that suffer from the attacks of these pests can also gain much relief by dusting the upper part of their stockings each morning with Persian insect powder, and by sprinkling a small quantity of this powder between the sheets of their beds at night. This order contains only a single family, the Pulicidoe (Pu-lic'i-dae), of which five or six genera and about twenty- five species are now known. The species that are most fre- quently observed are the following : — The Dog-flea, Ceratopsyllus serraticeps (Cer-a-to-psyl'lus ser-rat'i-ceps). — This is the most common flea that infests dog, cat, and man in this country (Fig. 598). It is reddish brown ; the lower margin of the head and the hinder margin of the prothorax each bear on each side from seven to nine black, tooth-like spines. The Human-flea, Pulex irritans (Pu'lex ir-ri'tans). This species lacks the comb-like rows of black spines on the lower side of the head and on the hinder margin of the prothorax. It is also usually darker than the preceding species, being sometimes pitchy brown. It is a common pest in dwellings in Europe, but is comparatively rare in this country. SIPHONAPTERA. 493 The Chigoe (Chig'o) or Jigger, Sarcopsylla penetrans (Sar-co-psyl'la pen'e-trans), is a small flea found in the West Indies and South America, which often causes serious trouble to men by burrowing beneath the skin of the foot. It is the fertile female that does this, and soon after enter- ing its host the body of the flee becomes distended with eggs and acquires the size of a pea. In the southern United States the names Chigoe and Jigger are improperly applied to the harvest-mites, which are the immature six-legged forms of various mites that attach themselves like ticks to the skin and become gorged with blood. CHAPTER XXI. Order COLEOPTERA (Co-le-op'te-ra). The Beetles. The members of this order have a pair of horny wing-covers, called elytra, which meet in a straight line down the back, and beneath which there is a single pair of membranous wings. The mouth-parts are formed for biting. The metamorphosis is complete. Beetles can be readily distinguished from all other in- sects except earwigs by the possession of horny, veinless wing-covers which meet in a straight line down the back (Fig. 599); and they differ from ear- wigs in lacking the pincer - like ap- pendages at the tail end of the body characteristic of those insects (see page 103). Beetles also differ from earwigs in having a complete meta- morphosis. The name of the order, Coleop- FlG- 599. tera, is from two Greek words: coleos, a sheath; andfteron, a wing. It refers to the sheath-like structure of the elytra (el'y-tra) or wing-covers, which were formerly believed to be modified wings. These wing-covers apparently occupy the position of the fore wings, and can be moved somewhat as wings are moved. Their structure, however, resembles that of the body-wall rather than that of wings ; and in some beetles (e.g., Dytiscus) rudiments of the fore wings exist beneath the elytra. 494 COLEOPTERA. 495 The homology of the elytra is most easily understood by a study of the corresponding parts in other orders of in- sects. In the lower orders of insects there exists at the base of each wing a small sclerite ; these have been termed the paraptera (pa-rap'te-ra), from the Greek para, beside, and pteron, a wing. In some of the orders of insects the paraptera of the mesothorax are in the form of a cup-like scale over the base of each fore wing, and are termed the tegul(B\ this form is well shown by most Hymenoptera. In the Lepidoptera they are even more prominent, and in many cases extend back a considerable distance on each side ; those of this order have been named the patagia. In the Coleoptera the paraptera of the mesothorax reach their greatest development, and so strongly resemble wings that they are still commonly believed to be the fore wings. The hind wings are membranous, and in most species very efficient organs of flight. But in some of the pre-eminently running beetles the hind wings are wanting, and the elytra serve only as a protection to the abdomen. With some of these insects the elytra are even grown together where they meet on the middle line of the back. Instances of this kind are not uncommon among the ground-beetles and the dark- ling beetles. The different mouth-parts are very evenly developed ; we do not find some of them greatly enlarged at the ex- pense of others, as in several other orders of insects. The upper lip, or labrum, is usually distinct ; the mandibles are powerful jaws fitted either for seizing prey or for gnawing; the maxillae are also well developed and are quite compli- cated, consisting of several distinct pieces; the maxillary palpi are usually prominent ; and the lower lip, or labium, is also well developed and complicated, consisting of several parts and bearing prominent labial palpi. The larvae are commonly called grubs. They are usually furnished with six thoracic legs, and often with a single proleg at the caudal end of the body ; some, however, as 496 THE STUD Y OF INSECTS. the larvae of the snout-beetles, are entirely destitute of jointed legs. The pupae have the partially developed elytra, • wings, and legs folded upon the breast, but in dis- tinct sheaths (Fig. 600). These insects usually transform in rude cocoons made of earth or of bits of wood fastened together by a viscid substance ex- creted by the larvae. Many wood-burrowing species transform in the tunnels made by the larvae ; and FIG. 600. some of the Dermestids as well as some of the lady-bugs transform in the last larval skin. Both beetles and their larvae vary greatly in their habits ; while some species are very beneficial to man, others are extremely noxious. More than eleven thousand species of beetles, represent- ing upwards of eighty families, are known to occur in Amer- ica north of Mexico. The following synopsis will aid the student in learning the relationships of these families : — -*^ SYNOPSIS OF THE COLEOPTERA. (See page $o$for a table for determining specimens.) A. THE TYPICAL COLEOPTERA. — Beetles with the head and mouth- parts of the ordinary form. B. THE ISOMERA (I-som'e-ra). — Typical Coleoptera in which the hind tarsi have as many segments as the others. (There are a few exceptions to this character among the Clavicornia.) C. Isomera in which the fourth and fifth tarsal segments are not grown together. D. THE ADEPHAGA (A-deph'a-ga) or Predaceous Beetles. — Isomera in which the first three ventral abdominal segments are grown together, and the first of these is divided by the hind coxal cavities so that the sides are separated from the very small medial part. The Tiger-beetles, p. 516 Family CICINDELIDJE. , The Ground-beetles, p. 518 Family CARABID^E.> The Amphizoids. p. 521 Family AMPHIZOID^E. The Haliplids. p. 522 Family HALIPLID^E. The Predaceous Diving-beetles, p. 523. Family DYTISCIDJE. • The Whirligig Beetles, p. 525 Family GYRINID^E. COLEOPTERA. 497 DD. THE CLAVICORNIA (Clav-i-cor'ni-a) or Clavicorn Beetles. — Isomera in which the first ventral abdominal segment is visible for its entire breadth, and in which the antennae are usually clavate or capitate, but not lamellate. The Water Scavenger Beetles, p. 527. Family HYDROPHILID^E. The Beaver-parasite, p. 529 Family PLATYPSYLLIDA:. The Leptinids. p. 529 Family LEPTINID^. The Carrion-beetles, p. 529 Family SILPHIDVE. The Scydmaenids. p. 531 Family SCYDM^ENID^E. The Pselaphids. p. 531 Family PSELAPHIDJE. The Rove-beetles, p. 532 Family STAPHYLINID^:. The Feather-wing Beetles, p. 533. Family TRICHOPTERYGIDJE. The Hydroscaphids. p. 533. Family HYDROSCAPHID^E. The Sphaeriids. p. 533 Family SPHJERIIDJE. The Scaphidiids. p. 533 Family SCAPHIDIID^:. The Phalacrids. p. 534 Family PH ALACRID^E. The Corylophids. p. 534 Family CORYLOPHID^E. The Lady-bugs, p. 534 Family COCCINELLIDJE. The Endomychids. p. 535 Family ENDOMYCHIDJE. The Erotylids. p. 536 Family EROTYLID/E. The Colydiids. p. 537 Family COLYDIID^E. The Rhyssodids. p. 537 Family RHYSSODID^:. The Cucujids. p. 537 Family CUCUJIDJE. The Cryptophagids. p. 538 Family CRYPTOPHAGID^E. The Mycetophagids. p. 538 Family MYCETOPHAGID^E. The Dermestids. p. 538... Family DERMESTID^E. The Histerids. p. 541 Family HISTERIDJE. The Nitidulids. p. 541 Family NlTlDULlDJE. The Trogositids. p. 542 Family TROGOSITID^E. The Monotomids. p. 542 Family MONOTOMID^E. The Lath rid i ids. p. 542 Family LATHRIDIID^. The Derodontids. p. 542 Family DERODONTIDJE. The Pill-beetles, p. 542 Family BYRRHID^E. The Georyssids. p. 543 Family GEORYSSID^E. The Parnids. p. 543 Family PARNID.E. The Heterocerids. p. 543 Family HETEROCERID/E. DDD. THE SERRICORNIA (Ser-ri-cor'ni-a) or Serricorn Beetles. — Isomera in which the first ventral abdominal segment is visible for its entire breadth, and in which the antennae are usually serrate. 498 THE STUDY OF INSECTS. The Dascyllids. p. 544 Family DASCYLLIDJE. The Rhipicerids. p. 544 Family RHIPICERID^E. The Click-beetles, p. 544 Family ELATERID^E. The Throscids. p. 548 . ..." Family THROSCID^E. The Buprestids. p. 548 Family BUPRESTID^E. The Fire-fly Family, p. 550. .T. Family LAMPYRIDJE. The Malachiids. p. 552 Family MALACHIID^E. The Checkered-beetles, p. 552 Family CLERIDJE. The Ptinids. p. 553 Family PTINID^E. The Cupesids. p. 553 Family CUPESID^E. The Ship-timber Beetle Family, p. 553. Family LYMEXYLID^E. The Ciids. p. 554 Family CIID^E. The Sphindids. p. 554 Family SPHINDID^. DDDD. THE LAMELLICORNIA (La-mel-li-cor'ni-a) or Lamelli- corn Beetles. — Isomera in which the first ventral abdominal segment is visible for its entire breadth and in which the antennae have a lamellate club. The Stag-beetles, p. 554 Family LUCANID^E. The Scarabaeids. p. 556 Family SCARAB^EID^:. CC. THE PHYTOPHAGA (Phy-toph'a-ga). — Isomera in which the fourth and fifth tarsal segments are grown together ; the fourth tarsal segment is usually very small, and concealed in a notch in the third segment. The Aberrant Long-horned Beetles, p. 566. Family SPONDYLIDJE. The Long-horned Beetles, p. 567 Family CERAMBYCID^E. The Leaf -beetles, p. 574 Family CHRYSOMELID^E. The Pea-weevil Family, p. 581 Family BRUCHIDJE. BB. THE HETEROMERA (Het-e-rom'e-ra) or Heteromerous Beetles. — Typical Coleoptera in which the fore and middle tarsi are five- jointed, and the hind tarsi four-jointed. The Darkling Beetles, p. 582 Family TENEBRIONID^E. The ^Egialitids. p. 584 Family ^EGIALITID^. The Cistelids. p. 584 Family CISTELIDJE. The Othniids. p. 584.. Family OTHNIIDJE. The Lagriids. p. 584 Family LAGRIID;E. The Monommids. p. 584 Family MONOMMID/E. The Melandryids. p. 585 Family MELANDRYID.E. The Pythids. p. 585 Family PYTHID^E. The CEdemerids. p. 585 .Family CEDEMERiDjE. The Cephaloids. p. 585 Family CEPHALOID^E. COLEOPTERA. 499 The Mordellids. p. 586 Family MORDELLID.E. The Anthicids. p. 586 Family ANTHICID.E. The Pyrochroids. p. 586 Family PYROCHROID^E. The Blister-beetles, p. 586 Family MELOID^E. The Rhipiphorids. p. 589 Family RHIPIPHORID^E. The Stylopids. p. 589 * Family STYLOPID^E. AA. THE RHYNCHOPHORA (Rhyn-choph'o-ra) or Snout- Beetles. — Beetles in which the head is more or less prolonged into a beak, and in which the palpi are short and rigid. The Rhinomacerids. p. 590 Family RHINOMACERID;E. The Rhynchitids. p. 591 Family RHYNCHITID^:. The Leaf-rolling Weevils, p. 591 Family ATTELABID^E. The Byrsopids. p. 591 Family BYRSOPID^E. The Scarred Snout-beetles, p. 592 Family OTIORHYNCHID^E. The Curculios. p. 593 Family CURCULIONID^E. The Brenthids. p. 594 Family BRENTHID;E. The Bill-bugs, p. 595 Family CALANDRID^E. The Engraver-beetles, p. 596 Family SCOLYTID^E. The Anthribids. p. 598 Family ANTHRIBID^E. CLASSIFICATION OF THE COLEOPTERA. {For Advanced Students.) In order to use the table for determining the families of beetles it is necessary that the student should become familiar with certain FIG. 601.— Head of Harpalus : a, dorsal aspect ; 6, ventral aspect; i, occiput; 2 epicranium; 3. eye; 5, clypeus; 6, FIG. 602. — Head and pro- gula; 7, antenna; 8, labrum; 10, mandibles; \id, maxillary thorax of Rhynchophorus: palpus; IT/, palea or outer lobe of maxilla; 12*, submen- tum; i2E (Staph-y-lin'i-dae). The Rove-beetles. The rove-beetles are very common about decaying ani- mal matter, and are often found upon the ground, under stones or other objects. They are mostly very small insects ; a few species, however, are of larger size, measuring a half inch or more in length. Their appearance is very charac- teristic, the body being long and slender, and the wing- covers very short (Fig. 640). The wings, however, are fully developed, often exceeding the abdomen in length ; when not in use the wings are folded beneath the short wing-covers. The abdominal segments are freely movable, and are seven or eight in number. It is interesting to watch one of these insects fold its wings ; frequently they find it necessary to make use of the tip of the abdomen or of one of the legs in order to get the wings folded beneath the wing-covers. The rove-beetles can run quite swiftly; and they have the curious habit, when disturbed, of raising the tip of the abdomen in a threatening manner, as if they could sting. As some of the larger species resemble wasps somewhat in the form of the body, these threatening motions are often as effective as if the creature really had a sting. As these insects feed upon decaying animal and vegetable matter, they should be classed as beneficial. The larvae re- semble the adults in the form of the body and are found in similar situations. About one thousand North American species of rove- beetles have been described. The great majority of them are small and exceedingly difficult to determine. Among the large species that are common are the following : — Creophilus villosus (Cre-oph'i-lus vil-lo'sus). — This species varies from one-half inch to nearly an inch in length. It is of a shining black color, spotted with patches of fine gray COLEOPTERA. 533 hairs. There is a conspicuous band of these across the middle of the wing-covers, and another on the second and third abdominal segments ; this abdominal band is best marked on the lower side of the body. Staphylinus maculosus (Staph-y-li'nus mac-u-lo'sus) is a larger species, which often measures fully an inch in length. It is densely punctured, and of a dull-brown color, with the scutellum black, and a row of obscure, square, blackish spots along the middle of the abdomen. Staphylinus vulpinus (S. vul-pi'nus) resembles the pre- ceding somewhat, but it has a pair of bright-yellow spots at the base of each abdominal segment. Lcistotroplius cingulatus (Leis-tot'ro-phus cin-gu-la'tus) is of about the same size as the preceding. It is brown, speckled with brownish-black spots, and the tip of its abdomen is clothed with golden hairs. The family TRICHOPTERYGID^E (Tri-chop-te-ryg'i-dae), or the Feather-wing Beetles, includes the smallest beetles that are known ; most of our species are less than one twenty- fifth of an inch in length, and in many cases they are not half that size. The most striking feature of the typical forms is the shape of the wings, which are long, narrow, and fringed with long hairs, being feather-like in appearance ; but in some species the wings are wanting. Some species live in rotten wood, muck, manure, and other decaying organic matter; a few have been found in ants' nests. The family HYDROSCAPHID^: (Hyd-ro-scaph'i-dae) is rep- resented in America by a single, minute, aquatic species from California. See table of families for its characteristics. The family SPH^ERIID^E (Sphae-ri'i-dae) is also repre- sented on this continent by a single Californian species. It lives in mud or under stones near water. Its distinguishing features are given in the table of families. The family SCAPHIDIID^E (Scaph-i-di'i-dae) includes less than twenty known North American species. They are 534 THE STUDY OF INSECTS. small, oval, very shining insects, found in fungi and rotten wood. The elytra are broadly truncate behind, not covering the entire abdomen. The family PHALACRID^E (Pha-lac'ri-dae) includes a small number of very small, convex, shining black beetles, which are sometimes two-spotted or tipped with red. They are found on flowers and sometimes under bark. The family CORYLOPHID^E (Cor-y-loph'i-dae) includes minute beetles found under damp bark and in decaying vegetable matter. The body is oval or rounded, and in many species is clothed with a grayish pubescence. The wings are wide, and fringed with long hairs. About twenty- five North American species are known. Family COCCINELLID>E (Coc-ci-nel'li-dae). The Lady-bugs, These insects are well known to nearly every child under the popular name given above. They are more or less nearly hemispherical, generally red or yellow, with black spots, or black, with white, red, or yellow spots. The larvae occur running about on foliage ; they are often spotted with bright colors and clothed with warts or with spines (Fig. 641). When ready to change to a pupa the larva fastens itself by its tail to any convenient object, and the skin splits open FTG. 64i. on the bade Sometimes the pupa state is passed within this split skin, and sometimes the skin is forced back and remains in a little wad about the tail (Fig. 642). With very few exceptions, the lady-bugs are pre- FIG. 642. daceous, both in the larval and adult states. They feed upon small insects and upon the eggs of larger species. The larvae of certain species are known as "niggers" by hop-growers, and are greatly prized by them ; for they are very destructive to the hop-louse. On the Pacific coast the lady-bugs are well known as the most beneficial of all insects i COLEOPTERA. 535 to the fruit-growers. Nothing more wonderful has been accomplished in economic entomology than the subduing in California of the cottony-cushion scale by the introduction from Australia of a lady-bug, Vedalia (Ve-da'li-a), which feeds upon it. Next in importance to the Vedalia on the Pacific coast are the twice-stabbed lady-bugs. Several species that occur on both sides of the continent are included under this popu- lar name. They are black, with a bright-yellow or reddish spot on each wing-cover. They are especially prized in California as they feed on the pernicious scale, the black scale, and other destructive species. A very common lady-bug in the East is Adalia bipunctata (A-da'li-a bi-punc-ta'ta). This species is figured on Plate I, Figure 3. It is reddish yellow above, with the middle of the prothorax black, and with a black spot on each wing-cover. It frequently passes the winter in our dwellings, and is found on the walls and windows in early spring. Under such circumstances it is often mistaken for the carpet-beetle and, unfortunately, destroyed. The Nine-spotted Lady-bug, Coccinella novemnotata (Coc-ci-nel'la no-vem-no-ta'ta) has yellowish wing- covers, with four black spots on each, in addition to a common spot just back of the scutellum (Fig. 643). The Herbivorous Lady-bug, Epilachna borealis (Ep-i- lach'na bor-e-a'lis), presents a remarkable exception in habits to what is the rule in this family. The larva of this species is herbivorous, feeding on the leaves of squash, pumpkin, and allied plants. It is yellow and is clothed with forked spines (Fig. 644). A pupa is shown in the figure near the upper right-hand corner. The adult is yellowish, with large black spots. The family ENDOMYCHID,E (En-do-mych'i-dae) includes a small number of species which are found chiefly in fungi. The body is usually more elongate than in the preceding 536 THE STUD Y OF INSECTS. family; the antennae are about half as long as the body; the prothorax is nearly square, and usually has a wide, thin margin, which is slightly turned upwards at the sides. FIG. 644. Family EROTYLID.E (Er-o-tyl'i-dae). The Erotylids (Er-ot1 y-lids). The members of this family are usually of moderate or small size; but some species are quite large, measuring three fourths inch or more in length. Some of our more common species are conspicuously marked with shining black and red. To the genus Megalodachne (Meg-a-lo-dach'ne) belong two common, large species, which are black, with two dull-red bands extending across the wing-covers. M. heros (M.he'ros) (Fig. 645) is two thirds of an inch or more in length. M, fasciata (M. fas-ci-a'ta) is about half an inch long. The genus Languria (Lan-gu'ri-a) includes FlG' 645 long, narrow species, which resemble click-beetles in form. I'ne) belong 1 COLEOPTERA. 537 Figure 646 represents L. mozardi (L. mo-zar'di) greatly enlarged. This is a reddish species with dark-blue wing- FIG. 646. covers ; the larva bores in the stalks of clover. The family COLYDIID^E (Col-y-di'i-dae) is composed of small insects which are usually of an elongate or cylindrical form, and are found under bark, in fungi, and in earth. Some of the species are known to be carnivorous, feeding on the larvae of wood-boring beetles. The tarsi are four- jointed ; the tibiae are not fitted for digging, and the first four abdominal segments are grown together on the ventral side. More than fifty North American species are known. The family RHYSSODID.E (Rhys-sod'i-dae) includes only four species, two from each side of the continent. They are elongate, somewhat flattened beetles, with the head and prothorax deeply furrowed with longitudinal grooves. They are found under bark. Family CUCUJID,E (Cu-cu'ji-dae). The Cucujids (Cu1 cu-jids). The insects of this family are very flat and usually of an elongate form ; most of the species are brown, but some are of a bright red color. As a rule they are found under bark and are believed to be carnivorous both in the larval and adult states ; but some feed in grain. 538 THE STUDY OF INSECTS. The most conspicuous of our common species is Cucujus clavipes (Cu'cu-jus clav'i-pes) (Fig. 647). This insect is about one half inch in length and of a bright red color, with the eyes and antennae black and the tibiae and tarsi dark. The most important member of this family is FIG. 647. tne Corn Silvanus, Silvanus surinamensis (Sil-va'- nus sur-i-na-men'sis), which is one of the small beetles that infest stored grain. This species is readily distinguished from other small beetles with similar habits by its flattened form and the saw-like edges of the prothorax. Besides grain it often infests dried fruits and other stores. It meas- ures from one tenth to one eighth of an inch in length. The family CRYPTOPHAGID.E (Cryp-to-phag'i-dae) in- cludes insects of small size, usually less than one tenth of an inch in length, and of variable form, but never very flat. The thorax is nearly or quite as wide as the wing-covers and the first ventral abdominal segment is somewhat longer than the others. They are generally of a light yellowish- brown color, and live on fungi and decomposing vegetable matter. The family MYCETOPHAGID^E (My-cet-o-phag'i-dae) is composed of small, oval, rarely elongate, moderately convex beetles. They are densely punctured and hairy, and are usually prettily marked insects. They live on fungi and under bark. Family DERMESTID^E (Der-mes'ti-dae). The Dermestids (Der-mes' tids). There are several families of small beetles that feed on decaying matter, or on skins, furs, and dried animal sub- stances. The most important of these is the Dermestidae. as several species belonging to this family destroy house- hold stores or goods. The Dermestids can be distinguished from most of the COLEOPTERA. 539 other beetles with similar habits by the fact that the wing- covers completely cover the abdomen. They are chiefly small beetles, although one of the common species measures one third inch in length. They are usually oval, plump beetles, with pale gray or brown markings, which are formed by minute scales, which can be rubbed off. These beetles have the habit of pretending that they are dead when they are disturbed ; they will roll over on their backs with their legs meekly folded and lie still for a long period. The larvae do much more damage than the adults. They are active, and are clothed with long hairs. These hairs are covered throughout their entire length with microscopic barbs. The Larder Beetle, Dermestes lardarius (Der-mes'tes lar-da'ri-us). — This pest of the larder is the most common of the larger members of this family. It is three tenths of an inch long, and black except the basal half of its wing-covers, which are pale buff or brownish yellow. This lighter portion is usually crossed by a band of black spots, three on each wing-cover (Fig. 648). The larva feeds on dead animal matter, as meat, skins, feathers and cheese. It is often a serious pest where bacon or ham are stored. When full grown it is about half an inch in length, dark brown above, whitish below, and rather thickly FIG. 648. covered with long, brown hairs. It is said that this insect can be attracted by baits of old cheese, from which they may be gathered and destroyed. The Carpet Beetle, Anthrenus scrophularia (An-thre'nus scroph-u-la'ri-ae). — During recent years this insect has be- come the worst of household pests, feeding in its larval state on carpets, woollens, furs, and feathers. The larva is well- known to many housekeepers as the Buffalo-moth. It is a short, fat grub, about one fifth of an inch in length when full grown, and densely clothed with dark brown hairs. It lives in the cracks of floors, near the edges of rooms, and be- neath furniture, where it eats holes in the carpet. It also 540 THE STUDY OF INSECTS. enters wardrobes and destroys clothing. The adult is a pretty little beetle which may be found in infested houses, in the spring, on the ceilings and windows. It is about one seventh of an inch in length and clothed with black, white, and brick-red scales (Plate I, Fig. I). There is a whitish spot on each side of the prothorax, and three irregular, whitish spots on the outer margin of each wing-cover ; along the suture where the two wing-covers meet there is a band of brick-red scales, which is widened in several places. It is worth while to learn to know this beetle ; for a Lady-bug (Plate I, Fig. 3), which often winters in our houses, is fre- quently mistaken for it. The Carpet Beetle in its adult state feeds on the pollen of flowers. Sometimes it abounds on the blossoms of currant, cherry, and other fruits. The best way to avoid the ravages of this pest is to use rugs in- stead of carpets, and to trap the larvae by placing woollen cloths on the floors of closets. By shaking such cloths over a paper once a week the larvae can be captured. The change from carpets to rugs is a very desirable one ; for carpets that are tacked to the floor and taken up only once or twice a year are unwholesome. The change need not be a very expensive one. As carpets wear out they may be replaced with rugs ; and good carpets can be made over into rugs. If the floors are not polished as is usually the case where it was planned to cover them with carpets, they can be made presentable by filling the cracks with putty and painting the boards where they are to be exposed. The museum pests, Anthrenus varius (An-thre'nus va'- ri-us) and Anthrenus museorum (A. mu-se-o'rum). — There are two minute species of this family that are a constant source of annoyance to those having collections of insects. The adult beetles measure less than one eighth of an inch in length, and are very convex. They deposit their eggs on specimens in our collections ; and the larvae feed upon the specimens, often destroying them. In order to preserve a collection of insects it is necessary that they should be kept COLEOPTERA. 541 in tight cases, so that these pests cannot gain access to them. Specimens should not be left exposed except when in use. And the entire collection should be carefully examined at least once a month. The injury is done by the larvae, which are small, plump, hairy grubs. Their presence is in- dicated by a fine dust that falls on to the bottom of the case from the infested specimens. These larvae can be destroyed by pouring a small quantity of car- bon bisulphide into the case, and keeping it tightly closed for a day or two. Benzine poured on a bit of cotton in the box will cause the pests to leave the specimens, when they may be taken from the box and destroyed. But we have found carbon bisulphide the better agent for the de- struction of these pests. The Raspberry Fruit-worm, Byturus unicolor (By-tu'rus u-ni-co'lor). — The fruit of the red raspberry is often infested by a small white worm, which clings to the inside of the berry after it is picked. This is the larva of an oval, pale, dull yellow beetle, which is densely clothed with short, fine, gray hairs. The beetle is represented enlarged in Figure 649; it measures about three twentieths of an inch in length. This insect is also injurious in the adult state, as it feeds on the bios- FlG-6«- soms of the raspberry. The family HlSTERID^E (His-ter'i-dae) includes certain easily recognized beetles which are found about carrion and other decomposing substances. They are mostly small, short, rounded, or somewhat square-shaped beetles, of a shining black color, with the-wing covers marked by lines v , of fine punctures and truncate behind, leaving two /Wk segments of the abdomen exposed (Fig. 650). In ffj some species the wing-covers are marked with red. F.G. 6So. The family NlTlDULiD^E (Nit-i-du'li-dae) com- prises small, somewhat flattened beetles. With many spe- cies the prothorax has wide, thin margins, and the wing- covers are more or less truncate, so as to leave the tip of the 542 THE STUD Y OF INSECTS. abdomen exposed ; but sometimes the elytra are entire. The tarsi are usually five-jointed, with the fourth segment very small ; they are more or less dilated ; the posterior coxae are flat, not sulcate ; the anterior coxae are transverse ; and the abdomen has five free, ventral segments. fOne of the most common representatives of this family is Ips fasciatus (Ips fas-ci-a'tus). (Fig. 651.) It is a shining black species, with two con- FIG. 65i. spicuous, interrupted, reddish bands across the wing-covers. The family TROGOSITID^E (Trog-o-sit'i-dae) includes ob- long, somewhat flattened beetles, of a black or reddish-black color. Most of them live under bark; but some are found in granaries. They differ from members of the preceding family in having slender tarsi, with the first segment very short. The family MONOTOMID^ (Mon-o-tom'i-das) is composed of a few small, depressed beetles, found mostly under the bark of trees. The wing-covers are truncate behind, leaving the last abdominal segment exposed. The family LATHRIDIID/E (Lath-ri-di'i-dae) includes very small beetles, which live under bark and stones and are sometimes caught flying in twilight. They are oblong ; the wing-covers are usually wider than the prothorax and entirely cover the abdomen. The family DERODONTID^E (Der-o-don'ti-dae) is repre- sented by a single species found in the East and two found in Oregon and northward. The eastern species is a small brown beetle with a tubercle on each side inside the eye. The family BYRRHID^E (Byr'rhi-dae) or the pill-beetles are short, very convex beetles of small or moderate size ; some, however, are half an inch in length. The body is clothed with hairs or minute scales. The legs can be folded up very compactly, the tibia usually having a furrow for the recep- tion of the tarsus. These beetles are found upon walks and CO LEO P TERA . 5 43 at the roots of trees and grass ; a few live under the bark of trees. The family GEORYSSID^E (Ge-o-rys'si-dae) includes only two American species. " They are small, rounded, convex, roughly sculptured, black insects, found at the margin of streams, on wet sand ; they cover themselves with a mass of mud, so that no part of the insect is visible." (LeConte and Horn.) The family PARNID^E (Par'ni-dae) includes small water beetles, in which the legs are not fitted for swimming. The tarsi are five-jointed ; the first four segments of the tarsi are short and equal ; the fifth is longer than the others con- joined ; the tarsal claws are unusually large. The body is clothed with fine, silken hairs, which retain a film of air when the insect is beneath the water. These beetles are found adhering to stones or plants beneath the surface of the water. The larva of Psephenus lecontei (Pse-phe'nus le-con'te-i) is common in the East, clinging to the lower surface of stones in rapid streams; and we have found it in muck near a spring. It is very flat and circular in outline (Fig. 652), and measures about five sixteenths of an inch in length. It is rarely recognized as an insect by the young collector. Other larvae of this family have similar habits, and resemble this species in form except that the margin of the body is notched between the segments. FIG. 652. The family HETEROCERID^: (Het-e-ro- cer'i-dae) includes only the genus Heteroccrus (Het-e-roc'e- rus). These beetles " are oblong or subelongate, oval, densely clothed with short silky pubescence, very finely punctate, and of a brown color, with the elytra usually vari- egated with undulated bands or spots of a yellow color. They live in galleries which they excavate in sand or mud at the margin of bodies of water, and, when disturbed, run from their galleries and take flight." (LeConte and Horn.) 544 THE STUD Y OF INSECTS. The family DASCYLLID^: (Das-cyl'li-dae) includes certain beetles that live on plants, usually near the water. The legs are short with slender tibiae ; the tarsi are five-jointed ; the posterior coxae are transverse, and dilated into a plate partly covering the femora ; the anterior coxae are transverse ; and the abdomen has five free, ventral segments, the fifth rounded at tip. About fifty species occur in North America. The larvae, of several species at least, live in rotten wood. The family R.HIPICERID.E (Rhip-i-cer'i-dae) is represented in this country by a very small number of species, which are most commonly found on cedars. The antennae are serrate in the females, frequently flabellate in the males. The an- terior and middle coxae are conical and prominent, the former with large trochantins ; the posterior coxae are transverse, and dilated into a small plate partly covering the femora. Family ELATERID^: (El-a-ter'i-dae). The Click-beetles or Elaters (El'a-ters). There is hardly a country child that has not been enter- tertained by the acrobatic performances of the long, tidy- appearing beetles called snapping-bugs, click-beetles, or skip-jacks (Fig. 653). Touch one of them and it at once curls up its legs, and drops as if shot ; it usually lands on its back, and lies there for a time as FIG. 653. if dead. Suddenly there is a click, and the insect pops up into the air several inches. If it comes down on its back, it tries again and again until it succeeds in striking on its feet, and then it runs off. We remember well carrying these creatures into the old district schoolhouse, where all lessons had to be learned from books, and where Nature was never given a chance to teach us anything. Here, with one eye on the teacher and one on this interesting jumper laid on our book behind the desk, we found a most fascinating occupation for the tedi- ous moments. But the end was always the same: the COLEOPTERA. 545 beetle jumped so high that it betrayed us and was liber- ated, and we were disgraced. Our common species of click-beetles are mostly small or of medium size, ranging from one tenth to three fourths of an inch in length. A few species are larger, some reaching the length of nearly two inches. The majority of the species are of a uniform brownish color; some are black or grayish, and some are conspicuously spotted (Fig. 654). The body is elongated, somewhat flattened, and tapers more or less towards each end ; the antennae are moderately elongated, and more or less FlG 6j4 _ A click. serrate ; the first and second abdominal seg- SS^.^IwtuMj ments are not grown together on the ventral size and enlareed- side ; and the hind coxae are each furnished with a groove for the reception of the femur. The larvae of click-beetles are long, narrow, worm-like creatures, very even in width, with a very hard .covering, and are brownish or yellowish white in color (Figs. 655 and FIG. 655. FIG. 656. 656). They are commonly known as wire-worms, a name suggested by the form and hardness of the body. Some wire-worms live under the bark of trees and in rotten wood ; but many of them live in the ground, and feed on seeds and the roots of grass and grain. In fact there is hardly a cultivated plant that they do not infest ; and, working as they do beneath the surface of the ground, it is extremely difficult to destroy them. Not only do they infest a great variety of plants, but they are very apt to attack them at the most susceptible period of their growth, before they have attained sufficient size and strength to withstand the attack ; and often seed is destroyed before it has germinated. Thus fields of corn or other grain are 546 THE STUDY OF INSECTS. ruined at the outset. The appearance of these insects when in the ground, as seen through the glass side of one of our root- cages, is shown in Fig. 657. There is a vast number of species of click- beetles ; more than five hun- FIG. 658.— Larva of Cryptohypnus abbre- ti iatus : a, clypeus; d, mandible; c. maxilla ; d, gula; e, caudal segment. FIG. 659.-Lar FIG. 657 -A corn-plant growing in a root- ^T^^S^SStl cage infested by wire-worms and click- guul • r> **" beetles (from a specimen in the Cornell ., . Insectary). The spotted beetle represented cJred have been described near the base of the plant is Drasterius elegans, that near the top of the plant is frOm North America alOHC. Agr totes mancus. It is quite difficult to sep- arate the closely-allied species, as there is but little variation in shape and color. The larvae also show comparatively COLEOPTERA. 547 little variation in form ; but in this stage the shape of the parts of the head and the last segment of the body often furnish reliable specific characters (Figs. 658 and 659). In those species that we have bred it requires several years for the larva to complete its growth. In these species the full-grown larva changes to a pupa in the latter part of the summer, in a little cell in the ground ; the pupa soon afterwards changes to an adult ; but the adult remains in the cell formed by the larva till the following spring. Although we tried an extensive series of experiments, extending over several years, we were unable to find any satisfactory way of destroying the larvae infesting field crops. But we found that if the cells containing pupae or recently-transformed adults were broken the insects per- shed. We conclude, therefore, that much can be done towards keeping these insects in check by fall-ploughing; for in this way many of the cells containing pupae or young adults would be broken. The Eyed Elater, Alaus oculatus (A'laus oc-u-la'tus). — Although most of our click-beetles are of moderate size, we have a few species that are large. The most common of these is the Eyed Elater (El'a-ter). This is the great pepper-and-salt-colored fellow that has two large, black, velvety, eye- like spots on the prothorax (Fig. 660). These are not its eyes, however. The true eyes are situated one on each side of the head near the base of the antenna. This insect varies greatly in size, some individ- uals being not more than half as large as others. The larger larvae are about two and a half inches long, and nearly four tenths of an inch wide across the middie of the body. They live upon decaying FlG- &°- wood, and are often found in the trunks of old apple-trees. There is an Elater quite similar to the preceding that 548 THE STUDY OF INSECTS. differs in having the eye-like spots less distinctly marked, and is not as common. This is Alaus myops (A. my'ops). The family THROSCID^E (Thros'ci-dae) includes a few small species which resemble the Elaters and Buprestids in having the prosternum prolonged behind into a process, which is received in the mesosternum. They differ from the Elaters in having the prothorax firmly joined to the mesothorax, and the front coxal cavities closed behind by the mesosternum instead of by the prosternum ; and from the Buprestids in having the ventral abdominal segments all free. The adult beetles are found on flowers. Family BUPRESTID/E (Bu-pres'ti-dae). The Metallic Wood-borers or Buprestids (Bu-pres' tids). The Buprestids resemble the click-beetles somewhat in form, being rather long and narrow; but they are easily recognized by their metallic coloring. Their bodies are hard and inflexible, and usually appear as if made of bronze ; but some species exhibit the brightest of metallic colors. The antennae are serrate; the first and second abdominal segments are grown together on the ventral side ; and these beetles do not have the power of springing when placed on the back. The adults are found upon flowers and upon the bark of trees, basking in the hot sunshine. Some of them fly very rapidly, with a loud buzzing noise ; and some drop to the ground when disturbed, and feign death. Most of the larvae are borers, feeding beneath bark or within solid wood. In such species the body is of a very characteristic form, which is commonly designated as " flat- headed." The flattened portion, however, is composed largely of the segments immediately following the head. The first thoracic segment is very wide and flat ; the next two or three segments are also flattened, but are successively smaller; while the rest of the body is quite narrow and cylindrical. These "flat-headed" larvae are legless, and COLE OP TERA. 5 49 have been compared to tadpoles on account of their form. Their burrows are flattened, corresponding with the shape of the larger part of the body. In some of the smaller species the larvae are cylindrical, and are furnished with three pairs of legs. These are leaf-miners; and in the adult state the body is much shorter than in the more typical species. The Virginian Buprestid, ChalcopJiora virginica (Chal- coph'o-ra vir-gin'i-ca). — This is the largest of our common Buprestids (Fig. 661). It is copper-colored, often almost black, and has its upper surface roughened by irregular, lengthwise furrows. This beetle appears late in spring in the vicin- ity of pine-trees. The larvae bore in the wood of pine, and are often very injurious. The Dicerca divaricata (Di-cer'ca di-var-i- ca'ta) is three quarters of an inch or more in FlG 66l> length, copper-colored or brassy above, with the wing-covers marked with square, elevated, black spots. The wing-covers taper very much behind, and are separated at the tips (Fig. 662). The larva bores in peach, cherry, beech, and maple. The Flat-headed Apple-tree Borer, ChrysobotJi- ris femorata (Chrys-o-both'ris fem-o-ra'ta). — This F.G. 662. js one Of the most injurious of all Buprestids. The adult (Fig. 663) is about half an inch long, and is a very dark green above, with bronze reflections, especially in the furrows of the wing-covers. It appears during June and July, and lays its eggs upon the trunk and limbs of apple, peach, oak, and other trees. The larvae at first bore into the bark and sap-wood, and FlG- 663- later into the solid wood. The transformations are com- pleted in one year. To prevent the ravages of this pest, the trees are rubbed with soap during June or July, or cakes of soap are placed in the forks of the trees, so that the rains will dissolve the soap and wash it down over the trunks. This is supposed to -t y ucu rv. i 550 THE STUDY OF INSECTS. prevent the beetles from depositing their eggs on the trees. After a tree is once infested, the larvae should be cut out with a gouge or a knife. Nursery stock that is infested should be promptly burned. The Red-necked Agrilus, Agrilus ruficollis (Ag'ri-lus ruf- ol'lis). — This beetle (Fig. 664) is about three tenths of an inch long. Its body is narrow and nearly cyl- indrical. The head is of a dark-bronze color, the prothorax of a beautiful coppery bronze, and the wing covers black. The larva bores in the stems of FIG. 664. raspberry and blackberry, causing a large swelling, known as the Raspberry Gouty-gall. These galls should be collected and burned in early spring. Family LAMPYRID^E (Lam-pyr'i-dae). The Firefly Family or Lampyrids (Lam-py rids). During some warm, moist evening early in our Northern June we are startled to see here and there a tiny meteor shoot out of the darkness near at hand, and we suddenly realize that summer is close upon us, heralded by her mysterious mes- sengers, the fireflies. A week or two later these little torch- bearers appear in full force, and the gloom that overhangs marshes and wet meadows, the dusk that shrouds the banks of streams and ponds, the darkness that haunts the borders of forests, are illumined with myriads of flashes as these silent, winged hosts move hither and thither under the cove." of the night. The fireflies are soft-bodied beetles of medium or small size, with slender, usually eleven-jointed, saw-like an- tennae. The prothorax is expanded into a thin pro- jecting margin, which in most cases completely covers the head (Fig. 665). The wing-covers are rather soft, and never strongly embrace the sides of FlG- 66s- the abdomen, as with most other beetles. Most members of this family are nocturnal insects, and COLEOPTERA. 55 1 are sluggish by day. On the other hand, a few species are very active in the brightest sunshine. The most common of these day-fliers are the soldier- beetles, Chauliognatkus (Chaul-i-og'na-thus). These are very abundant in late summer and autumn on various flowers, but especially on those of the goldenrod. There are two very common species : the Pennsylvania Soldier-beetle, Chauliog- nathus pennsylvanicus (C. penn-syl-van'i-cus), which is yellow, with a black spot in the middle of the prothorax and one near the tip of each wing-cover (Fig. 666) ; and the Margined FIG. 666. FIG. 667. FIG. 668. Soldier-beetle, C. marginatus (C. mar-gi-na'tus). This species (Fig. 667) may be distinguished from the former by the head and lower part of the thighs being orange. The beetles of this genus are remarkable for having an extensible, fleshy filament attached to each maxilla. These filaments are probably used in collecting pollen and nectar from flowers. Another common diurnal Lampyrid is Calopteron reticu- latum (Ca-lop'te-ron re-tic-u-la'tum) (Fig. 668). This species represents a group in which the wing-covers are covered with a network of fine elevated lines. These insects are found on the leaves of plants, where they seek and feed upon other insects. The true Fireflies are nocturnal, and are furnished with a light-giving apparatus, which is situated on the lower side of the abdomen ; the exact position of these organs differs in different genera. Figure 665 represents a common species. 552 THE STUDY OF INSECTS. The family MALACHIID.E (Mal-a-chi'i-dae) is composed chiefly of small or very small beetles, found on flowers, and on the ground near water. They vary greatly in form ; but bear a general resemblance in structure to the preceding family, from which they can be distinguished by the presence of only six ventral abdominal segments. Some members of the family are furnished with soft, orange-colored vesicles which they protrude from the sides of the body, and which are supposed to be scent organs for defence. One of our most common representatives is Collops qiiadriinaculatus (Col'lops quad-ri-mac-u-la'tus), which Fl is yellowish orange, with the top of the head and four spots on the wing-covers bluish black (Fig. 670). Family CLERID^: (Cler'i-dae.) The Checkered Beetles. The family Cleridae includes a considerable number of species which are found on flowers and on the trunks of trees. Many of them are beautifully marked with strongly contrasting colors; this has suggested the common name checkered beetles for them. Frequently they are more or less ant-like in form, the prothorax being in these cases narrower than the wing-covers, and slightly narrower than the head. The abdomen has either five or six ventral seg- ments ; the anterior coxae are conical, prominent, and con- tiguous, or very slightly separate ; the hind coxae are trans- verse, not prominent, and covered by the femora in repose ; the legs are slender ; and the tarsi are five-jointed. In the larval state these insects are usually carnivorous, living under bark and in the burrows of wood-boring insects, upon which they prey; some are found in the nests of bees ; and still others feed on dead animal matter. Figure 671 represents one of our more common species, Trichodes nuttalli (Tri-cho'des nut-tal'li). COLEOPTERA. 553 i The family PTINID.E (Ptin'i-dae) or the Death-watch Family is composed of small insects, which rarely exceed a quarter of an inch in length, and very many of them are not half that length. They are usually of a cinnamon-brown color, but not always so. The most distinctive structural feature is the position of FlG- 6?1- the trochanters, which are situated between the femora and coxae, instead of at one side of the base of the femur in each case. These insects usually live upon dead vegetable matter, and frequently upon that which has begun to decay ; but some bore into solid wood, and others attack living plants. One of the latter is the Apple-twig Borer, Amp/iicerus bicaudatus (Am-phic'e-rus bi-cau-da'tus), which often injuriously affects the twigs of apple-trees ; the adult beetle is about three tenths of an inch long, and the male has two thorn-like pro- jections from the ends of the wing-covers. The Cigarette Beetle, Lasioderma serricorne (Las-i-o-der'ma ser-ri-cor'ne) is a serious pest in tobacco manufactories, infesting the dried tobacco-leaves and the manufactured products. Sitodrepa panicea (Si-tod're-pa pa-nic'e-a) is a cosmopolitan species, which feeds on many kinds of dead organic matter, both animal and vegetable. It sometimes assumes the role of a bookworm. We have bred it in large numbers from the cover of a very old book, a copy of Dante's Divine Comedy printed in 1536. It seems that old books are much more subject to the attacks of bookworms than others. The family CUPESID/E (Cu-pes'i-dae) includes only four American species. These are found under the bark of de- caying trees, and sometimes in houses. The body is covered with small scales; other characteristics are given in the table of families. The family LYMEXYLID/E (Lym-ex-yl'i-dae) is also a very small family. It is represented in this country by only three species. Its chief interest lies in the fact that it includes the Ship-timber beetle, Lymexylon navale (Ly-mex'y-lcm na- va'le) of Europe. 554 THE STUDY OF INSECTS. The family CllD/E (Ci'i-dae) includes a small number of very small beetles, found under the bark of trees and in the dry and woody species of fungus. The body is cylindrical ; the prothorax is prolonged over the head ; the abdomen has five ventral segments, of which the first is longer than the others ; and the tarsi are all four-jointed. The family SPHINDID^: (Sphin'di-dae) is represented in North America by only three small species, which are found in dry fungi, which grow on the trunks of trees. Although the antennae are clubbed, and these beetles are commonly regarded as belonging to the Clavicornia, the tarsi -are like those of the Heteromera, the fore and middle tarsi being five-jointed and the hind tarsi four-jointed. Family LUCANIDJE (Lu-can'i-dae). The Stag-beetles. The stag-beetles are so called on account of their large mandibles, which in the males of some species are branched like the antlers of a stag. But they are more surely distin- guished by the form of the antennae, which are lamellate ; but the plates composing the club are not capable of close apposition, and usually are not flattened. The student should carefully distinguish between this type of antenna and that of the Scarabaeidae, where the terminal segments are greatly flattened and can be brought close together so as to form a compact club. The adult beetles are found on the trunks of trees, and are said, by Harris, to live upon sap, for procuring which the brushes of their jaws and lips seem to be designed ; but it seems probable that some species at least feed upon decom- posing wood. They lay their eggs in crevices of the bark of trees, especially near the roots. The larvae that hatch from these eggs resemble the well-known larvae of May-beetles in form. But, unlike the white grubs which feed on the roots of herbaceous plants, the larvae of stag-beetles bore into the solid wood of the trunks and roots of trees, and reduce it to COLEOPTERA. 555 a substance resembling very coarse sawdust. They mature slowly ; it is said that the larvae of some of the larger species require six years to complete their growth. The family is a small one ; only fourteen North Ameri- can species are at present known. The Common Stag-beetle, Lucanus dama (Lu-ca'nus da'- ma). — The most common of our Stag-beetles is this species (Fig. 672). It flies by night with a loud buzzing sound, and is often at- tracted to lights in houses. The larva is a large whitish grub resembling the larvae of the Lamellicorn Beetles. It is found in the trunks and roots of old, partially decayed trees, especially apple, cherry, willow, and oak. The specimen figured here is a male;, in the female the mandibles are shorter. The Giant Stag-beetle, Lucanus elaphus (L. el'a-phus), is a large species found in the South. It measures from one and one-half inches to two inches in length, not including the mandibles, which in the case of the male are more than half as long as the body, and branched like the antlers of a stag. The Antelope Beetle, Dorcus parallelus (Dor'cus par-al-le'lus). — This beetle is somewhat smaller than the species of Lu- canus, and differs in having the wing-covers marked with longitudinal striae and the teeth on the outside of the fore tibiae much smaller (Fig. 673.) Several species of stag-bee- tles that are much smaller than Dorcus are found in this FIG. 674. country. Fie. 672. FIG. 673. 556 THE STUDY OF INSECTS. The Horned Passalus, Passalus cornutus (Pas'sa-lus cor- nu'tus). differs greatly in appearance from our other stag- beetles (Fig. 674). It is a large shining, black beetle, with a short horn, bent forwards, on the top of the head. This beetle and its larva are found in decaying wood. The larva is remarkable for possessing only four well-developed legs. Family SCARAB^EID^E (Scar-a-bae'i-dae). The Scarabceids (Scar-a-bce' ids) or the Lamellicorn (La-mel'li- corn) Beetles. This is a very large family, including beetles that repre- sent a wide range of variation in size, form, and habits. They are mostly short, stout-bodied beetles, of which the well-known June-bugs or May-beetles represent the most familiar type. The most useful character for distinguishing these insects is the lamellate form of the club of the antennae, the segments constituting it being greatly flattened, and capable of being brought close together. It is this character that suggests the name lamellicorn beetles. According to their habits, the members of this family can be separated into two well-marked groups — the scavengers and the leaf-chafers. THE LAMELLICORN SCAVENGERS. The lamellicorn scavengers in both the larval and adult states feed upon decaying animal and vegetable matter. Nearly all the species live in the dung of" animals, chiefly that of horses and cows. But the members of one genus, Trox, feed upon decaying animal matter, and. a few species feed upon fungi. The following are the most common represen- tatives of this division : I. The Trimble-bugs. — These are the most familiar of all dung-beetles, for their peculiar habits have attracted much at- tention from the earliest times. They are of rounded form, and the wing-covers are shortened so as to expose the tip COLEOPTERA. 557 of the abdomen. They are generally black, but some are colored with rich metallic hues. They vary greatly in size. The name tumble-bug refers to the habit which many species exhibit of forming round balls of dung, which they roll long distances. They work in pairs, a male and a female working together ; and often the ball is several times as large as their combined size. They finally bury the ball in the ground, and the female deposits an egg in one side of it ; this partially decomposed matter serves as food for the larva when it hatches. It should be noted that this is one of the instances, rare among insects, where the male realizes that he has some responsibility as a father, and assists the female in providing for the young. This strange habit of rolling these balls has occasioned much speculation as to its object, and has been the source of many superstitions, especially in ancient times. The only reasonable theory that we have met is that as many predaceous insects frequent the masses of dung from which the balls are obtained, in 'order to prey upon the larvae which live there, the more intelligent tumbje-bugs remove the food for their larvae to a safe distance. The most noted member of this group of genera is the Sacred Beetle of the Egyptians, Ateuchus sacer (A-teu'chus sa'cer). This insect was held in high veneration by this ancient people. It was placed by them in the tombs with their dead ; its picture was painted on sarcophagi, and its image was carved in stone and precious gems. These sculp- tured beetles can be found in almost any collection of Egyptian antiquities. From the habits and structure of this Scarabaeid the Egyptians evolved a remarkable symbolism. The ball, which the beetles were supposed to roll from sunrise to sunset, represented the earth ; the beetle itself personified the sun, because of the sharp projections on its head, which extend out like rays of light ; while the thirty segments of its six tarsi represented the days of the month. All indi- 558 THE STUDY OF INSECTS. viduals of this species were thought to be males, and a race of males symbolized a race of warriors. This latter super- stition was carried over to Rome, and the Roman soldiers wore images of the Sacred Beetle set in rings. Our common tumble-bugs are distributed among three genera : Canthon, Copris, and Phanceus. In the genus Can- thon (Can'thon) the middle and posterior tibiae are slender, and scarcely enlarged at the extremity. Cant/ton Iczvis (C. lae'vis) is our most common species (Fig. 675). In Copris (Co'pris) and Phanceus (Pha-nae'us) the middle and posterior tibiae are dilated at' the ex- tremity. In Phanczus the fore tarsi are want- ing, and the others are not furnished with claws ; the species are brilliantly colored. KIG. 675." PhancBiis carnifex (P. car'ni-fex), with its rough copper-colored thorax and green elytra, is one of our most beautiful beetles, and is our best-known species. It is about two thirds inch in length, and the head of the male is furnished with a prominent horn. In Copris all the tarsi are present and furnished with claws. Copris Carolina is a large well-known species, which measures more than one inch in length. II. 77/(? Aphodian (A-pho'di-an) Dung-beetles. — These are small insects, our common species measuring from one sixth to one third inch in length. The body is oblong, convex, or cylindrical in form, and, except in one small genus, the clypeus is expanded so as to cover the mouth- parts entirely. These insects are very abundant in pastures in the dung of horses and cattle, and immense numbers of them are often seen flying through the air during warm autumn afternoons. More than one hundred North Amer- ican species have been described ; of these seventy belong to the genus Aphodius (A-pho'di-us). One of the more common species is Aphodius fimetarius (A. fim-e-ta'ri-us), which is about one third inch in length, and is easily recog- nized by its red wing-covers. COLEOPTERA. 559 III. The Earth-boring Dung-beetles. — These beetles are of a rounded convex form (Fig. 676). They differ from all other dung-beetles in having the antennae eleven-jointed, and in the labrum and man- dibles being visible from above. This is a small group, less than twenty North American species having been described. The popular name is derived from that of the typical genus, F,G 6?6 Geotrupes (Ge-o-tru'pes), which signifies earth-boring. Those species the habits of which are known live in excrement. The females bore holes into the earth either beneath the dung or near it ; into these holes they convey a quantity of the dung: this is to serve as food for the larvae, an egg be- ing laid in each hole. This is an approach to the peculiar habits of the tumble-bugs. IV. The Skin-beetles— 1\\z members of this group are oblong, convex species, in which the surface of. the body and wing-covers is usually very rough, and covered with a * crust of dirt, which is removed with great dif- ficulty. They are small or of medium size ; our most common species measure from one third to one half inch in length. The abdomen is FIG. 677. covered by the elytra ; the feet are hardly fitted for digging, but the femora of the front legs are greatly di- lated. Our species all belong to the genus Trox (Fig. 677). They feed upon dried, decomposing animal matter ; many species are found about the refuse of tanneries, and upon the hoofs and hair of decaying animals. THE LAMELLICORN LEAF-CHAFERS. The leaf-chafers are herbivorous insects which in the adult state usually feed upon the leaves of trees, but many of the species devour the pollen and petals of flowers. In the larval state some of these insects are found in rotten wood ; others live in the ground, where they feed upon the roots of grass and other plants. These larvae are thick, 560 THE STUDY OF INSECTS. fleshy grubs, with well-developed legs (Fig. 678). The caudal segments of the abdomen are very large, and appear black on account of the large amount of dirt in the intestine. The body is strongly curved, so that the larvae can crawl only with great difficulty ; when in the ground they usually lie on their FIG. 678. backs. The following groups include the more important repre- sentatives of this division : — I. The May-beetles or June-bugs. — During the warm evenings of May and June we throw open our windows so that we may feel the refreshing coolness of the night air and the inspiration of the new summer. Suddenly, as we sit working or reading, our peace is disturbed by a buzzing object which whirls above us. Then comes a sharp thud and silence. A little later the scratching of six pairs of tiny claws tells us the whereabouts of the intruder. But so familiar are we with his kind that we need not look to know how he appears, the mahogany-brown blunderer, with yellowish wings sticking out untidily from under his polished wing-covers. Although these insects are beetles, and attract our atten- tion each year in May, they have received the infelicitous title of June-bugs. They are more properly termed May- beetles. The May-beetles belong to the genus LacJmosterna (Lach-no-ster'na), of which we have more than sixty species. The adults frequently do much injury by eating the foliage of trees. In the case of large trees this injury usually passes unnoticed ; but small trees are often completely defoliated by them. When trouble- some, they can be easily gathered by shaking them from trees upon sheets. Figure 679 represents a common species. COLEOPTERA. $6 1 The larvae of the different species of May-beetles are commonly classed together under the name " white grubs." They are often great pests in meadows and in cultivated fields. We have known large strawberry plantations to be destroyed by them, and have seen large patches of ground in pastures from which the dead sod could be rolled as one would roll a carpet from a floor, the roots having been all destroyed and the ground just beneath the surface finely pulverized by these larvae. No satisfactory method of fighting this pest has been discovered as yet. If swine be turned into fields infested by white grubs they will root them up and feed upon them. We have destroyed great numbers of the beetles by the use of trap-lanterns, but many beneficial insects were destroyed at the same time. II. The Rose-bugs. — The common rose-bug, Macrodaclylus subspinosus (Mac-ro-dac'ty-lus sub-spi-no'sus), is a well-known pest. It is a slender beetle, tapering before and behind, and measuring three eighths inch in length (Fig. 680). It is thickly clothed with fine, yellow, scale-like //^|jriv hairs, which give it a yellow color; the legs are !/ \ long, slender, and of a pale-red color. These beetles FIG 680. appear in early summer, and often do great injury to roses and other flowers, and to the foliage of various fruit-trees and shrubs. This is a very difficult pest to con- trol. The best method now known is to use Paris-green when safe to do so ; in other cases the beetles should be collected by jarring them into a large funnel which is fitted into a can. The larvae of rose-bugs feed on the roots of plants. III. The SJiining Leaf-cJiafers. — These insects resemble the May-beetles in form, but can be distinguished from them by the position of the hinder pair of spiracles, which are visible on the sides below the edges of the wing-covers; and they differ from the other leaf-chafers in which the spiracles are in this position in that the tarsal claws are of unequal size, one claw of each pair being larger than the other. 562 THE -STUDY OF INSECTS. These beetles are usually polished, and many of them are of brilliant colors. To this family belong the most beautiful beetles known, many appearing as if made of burnished gold or silver, or other metal. The Goldsmith-beetle, Cotalpa lanigera (Co-tal'pa la- nig'e-ra). — This is one of our most beautiful species. It measures a little less than one inch in length, and is a broad oval in shape. It is of a lemon-yellow color above, glittering like burnished gold on the top of the head and thorax ; the under side of the body is copper-colored and thickly covered with whitish wool. The Spotted Pelidnota, Pelidnota punctata (Pel-id-no'ta punc-ta'ta). — This beetle is reddish brown above, with three black spots on each wing- cover and one on each side of the prothorax (Fig. 68 1). The scutellum, base of the head, and the entire body beneath are of a deep bronzed-green color. The adult is commonly found feeding on the leaves of grape. The larva feeds upon decaying roots and stumps of 681' various trees. The Light-loving Anomala, Anomala lucicola (A-nom'a-la lu-cic'o-la). — This also feeds on the leaves of grape. It resembles the preceding species in form, but is much smaller, measuring onlyabout one third inch in length. It is of a pale dull yellow color; the prothorax is black, margined with dull yellow, and the hinder part of the head and the ventral side of the body are also black ; sometimes the abdomen is brown. As this beetle appears early in the summer, it can be safely destroyed with Paris-green, for the subsequent rains will wash the poison from the vines before the fruit ripens. IV. The Rhinoceros-beetles.— The name rhinoceros-beetles was suggested for this group by the fact that in many species the male bears a horn on the middle of the head. In addi- tion to this horn there may be one or more horns on the COLEOPTERA. 563 thorax. These beetles are of medium or large size ; in fact, the largest beetles known belong to this group. As with the flower-beetles, the claws of the tarsi are of equal size, but the fore coxae are transverse, and not promi- nent. One of the largest of our rhinoceros-beetles is Dynastes tityrus (Dy-nas'tes tit'y-rus). This is of a greenish-gray, color, with scattered black spots on the wing-covers, or, if only recently transformed, of a uniform dark brown. The FIG. 682. male (Fig. 682) bears a prominent horn on the top of his head, and a large one and two small ones on his prothorax. The female has only a tubercle on the head. This insect is found in the Southern States ; the larva lives in rotten wood. In the far West there is a closely allied species, Dynastes grantii (D. gran'ti-i), in which the large horn on the thorax is twice as long as in D. tityrus. In the West Indies there occurs a species, Dynastes hercules (D. her'cu-les), which measures six inches in length. Several other genera occur in this country, in some of which the males have prominent horns ; in others the horns are represented-by tubercles, or are wanting. The following species represents the latter type. The Sugar-cane Beetle, Ligyrus rugiceps (Lig'y-rus ru'gi-ceps). — This beetle is a serious pest in the cane-fields of Louisiana, and it sometimes injures corn. Figure 683 represents the adult, and its method of attacking a plant. 564 THE STUD Y OF INSECTS. V. The Flower-beetles. — The flower-beetles are so called because many of them are often seen feeding upon pollen and flying from flower to flower. These beetles are some- what flattened, or nearly level on the back ; the claws FIG. 683.-The Sugar-cane Beetle. of the tarsi are of equal size, and the fore coxae are coni- cal and prominent. Nearly sixty species occur in this country. CO LEO P TERA . $65 The Hermit Flower-beetle, Osmoderma eremicola (Os-mo- der'ma er-e-mic'o-la). — This is one of the larger of our Flower-beetles (Fig. 684). It is of a deep mahogany-brown color, nearly smooth, and highly polished. It is sup- posed that the larva lives on decaying wood in forest-trees. The Rough Flower-beetle, Osmoderma scabra (O. sca'bra), is closely allied to the preceding. It is not quite as large, meas- uring about one inch in length. It is purplish black, and the wing-covers are roughened with irregular, coarsely-punc- tured striae. It is nocturnal, concealing FIG. 684. itself during the day in the crevices and hollows of trees. The larva lives in the decaying wood of apple and cherry, consuming the wood and inducing more rapid decay. The Bumble Flower-beetle, Euphoria inda (Eu-pho'ri-a in'da). — The most common of our Flower-beetles, at least in the North, is a yellowish-brown one, with the wing-covers sprinkled all over with small, irregular black spots (Fig. 685). It is one of the first in- sects to appear in the spring. It flies near the surface of the ground with a loud humming sound, like that of a bumble-bee, for which it is often mistaken. During the summer months it is FIG. 685. not seen . but a new brood appears about the middle of September. The adult is a general feeder occur- ring upon flowers, eating the pollen ; upon corn-stalks and green corn in the milk, sucking the juices ; and upon peaches, grapes, and apples. Occasionally the ravages are very serious. The genus Euphoria represents well the form of the more typical Flower-beetles, which are distinguished by the margin of each wing-cover having a large wavy indentation near its base, which renders the side pieces of the meso- 566 THE STUDY OF INSECTS. thorax visible from above. This indentation makes it un- necessary for these insects to raise or expand their wing- covers when flying, as most beetles do, as they are able to pass the wings out from the sides. The Sad Flower-beetle, Euphoria melancholica (Eu-pho'- ri-a mel-an-chori-ca).— This is a much smaller species than the Bumble Flower-beetle, measuring hardly half an inch in length. It is almost black, with irregular transverse white lines on the wing-covers. We have received several reports of its producing injuries similar to those of E. inda. The Fig-eater, Allorhina nitida (Al-lo-rhi'na nif.'i-da). — This species extends over the Atlantic slope, and is very common in the South. It is a green, velvety insect, measur- ing from two thirds of an inch to one inch in length. It is somewhat pointed in front, and usually has the sides of the thorax and elytra brownish yellow. These beetles often fly in great numbers at night, making a loud buzzing noise similar to that of the May-beetles. In fact, in the South the term June-bug is often applied to this insect. The larvae feed upon the roots of grass and other plants. Sometimes they leave the ground and crawl from one place to another. When they do so they, strangely enough, crawl upon their backs, making no use of their short legs. On one occasion we saw them crawling over the pavements on the Capitol grounds at Washington in such numbers that bushels of them were swept up and carted away. The family SPONDYLID.E (Spon-dyl'i-dae), or aberrant long-horned beetles, includes only four North American FIG. 686. FIG. 687. COLEOPTERA. 567 species. These live under the bark of pine-trees. They are closely allied to the Cerambycidae, but differ in the form of the tarsi and in the structure of the antennae. The fourth segment of the tarsus, although much reduced in size, is distinctly visible ; the first three segments are but slightly dilated, and the third is either bilobed or not (Fig. 686). The segments of the antennae have deep impressions, in which are situated the organs of special sense (Fig. 687). The most common species is Parandra brunnea (Pa-ran'dra brun'ne-a) (Fig. 688) ; this insect is of a mahogany-brown color. ^ Family CERAMBYCIDAE (Cer-am-byc'i-dae). The Long-horned Beetles or Cerambycids (Ce-ram'by-cids}. This is a very large family, there being about six hun- dred described species in North America alone. As a rule the beetles are of medium or large size, and graceful in form ; many species are beautiful in color. The body is oblong, often cylindrical. The antennae are long, often longer than the whole body ; but except in one genus, Prionus, they are only eleven-jointed, as with most beetles. The legs are also long, and the tarsi are apparently four-jointed, the fourth segment being very small and hidden ; the third segment of the tarsi is strongly bilobed (Fig. 689). They are strong fliers and swift runners; but many of them have the habit of remaining motionless on the limbs of trees for long intervals, and when in this apparent trance they suffer themselves to be picked up. But, when once caught, many species make an indignant squeak- ing by rubbing the prothorax and mesothorax to- gether. The larvae are borers, living within the solid parts of trees or shrubs, or beneath bark. They are white or yellowish grubs. The body is soft, and °' tapers slightly from head to tail (Fig. 690) ; the jaws are powerful, enabling these insects to bore into the 568 THE STUDY OF INSECTS. hardest wood. The larval state usually lasts two or three years. The pupa state is passed within the burrow made by the larva ; frequently a chamber is made by partitioning off a section of the burrow with a plug of chips ; but some- times the larva builds a ring of chips around itself just beneath the bark before changing to a pupa. The pupal state is comparatively short, lasting only a few days or weeks. This family comprises three subfamilies, which are sep- arated by Le Conte and Horn as follows : — A. Sides of the prothorax with a sharp margin, p. 568. PRIONINJE. AA. Prothorax not margined. B. Front tibiae not grooved; palpi never acute at tip. p. 569. CERAMBYCINJE. BB. Front tibiae obliquely grooved on the inner side ; palpi with the last segment cylindrical and pointed, p. 572 LAMIIN^E. Subfamily PRICKING (Pri-o-ni'nae). The Prionids (Pri-o'nids\ The larger of the Long-horned Beetles constitute this subfamily. They are distinguished from other Cerambycids by having the sides of the prothorax prolonged outwards into a thin margin, which is more or less toothed. The wing-covers are usually leathery in appearance, and of a brownish or black color. The following are our best-known species : — The Broad-necked Prionus, Pri- onus lalicollis (Pri-o'nus lat-i-col'- lis). — This is the largest of our common species ; but the individ- uals vary from less than one inch FlG' 68. the base of the prothorax in the latter (Fig. 708), but do not in the former. The Argus-tortoise, Clielymorpha argus (Chel-y-mor'pha ar'gus), is a large brick-red species, which measures from three eighths to seven sixteenths of an inch in length, and has the prothorax and wing-covers marked with many black spots. This species feeds on milkweed (Asclepias). Family BRUCHID.E (Bru'chi-dae). The Pea-weevil Family . These are small beetles, the larvae of which live in the seeds of leguminous plants. The head of the adult is prolonged into a broad beak ; and the wing-covers are rather short, so that the tip of the abdomen is always exposed (Fig. 709). The Pea-weevil, BrucJius pisi (Bru'chus pi'si). — FIG. 709. " Buggy-peas " are well known in most sections of our country ; but just how the " bugs " find their way into 582 THE STUDY OF INSECTS. the peas is not so generally understood. The eggs of the Pea-weevil are laid upon the pod while the peas are quite small ; when the larvae hatch they bore through the pod into the young peas. Here they feed upon the substance of the seed, which ripens, however, and in some cases will germinate when planted. The larva before transforming eats a circular hole on one side of the seed, leaving only a thin scale, which is easily pushed away by the mature beetle. The adult is about one fifth inch in length ; it is dark brown, with a few white spots on the wing-covers, and one on the prothorax near the middle. Sometimes the beetles leave the peas during the autumn or winter ; but as a rule they remain in the seed till spring, and are often planted with it. Seed peas should be placed in water, and the infested ones, which will float, should be picked out and destroyed. This species is not known to oviposit on dry peas. This and other grain-infesting insects can be destroyed by placing the grain into a close receptacle with a small quantity of bisulphide of carbon. The Bean-weevil, Bruclms obtectus (B. ob-tec'tus). — This species resembles the preceding quite closely ; but it is a little smaller (Fig. 709), and lacks the white markings char- acteristic of B. pisi. It infests beans, and often several indi- viduals inhabit a single bean. The eggs are laid within the pod, being pushed through a slit which the female gnaws through the pod. This species will oviposit on dry beans, peas, and other grain, and will continue to breed for many generations in stored beans and peas. Family TENEBRIONID.E (Te-neb-ri-on'i-dae). The Darkling Beetles. The darkling beetles are nearly all of a uniform black color, although some are gray, and a few are marked with bright colors. The different species vary greatly in size and COLEOPTERA. $83 in the form of the body. As with the blister-beetles, the hind tarsi are four-jointed, and the fore and middle tarsi are five-jointed ; but unlike the members of that family, the body and wing-covers are firm, and the head is narrower than the prothorax. These insects occur chiefly in dry and warm regions. Thus while we have comparatively few species in the North- eastern United States, there are many in the Southwest. Most of the species feed on dry vegetable matter, and often on that which is partially decomposed ; some live in dung, some in dead animal matter, others in fungi, and a few prey upon larvae. More than four hundred species occur in this country. The three following will serve to illustrate the variations in form and habits : — The Meal-worm, Tenebrio molitor (Te-neb'ri-o mori-tor). — This is a well-known pest in granaries and mills. The larva is a hard, waxy-yellow, cylindrical worm, which meas- ures when full grown an inch or more in length, and closely resembles a wire-worm ; it feeds on flour and meal. The beetle is black, and about five eighths of an inch in length (Fig. 710). The Forked Fungus-beetle, Boletotherus bifur- cus (Bol-et-o-the'rus bi-fur'cus), is common in the ] Northeastern United States and in Canada about the large toadstools (Polyporns) which grow on the sides of trees. The surface of the body and wing-covers is very rough, and the prothorax bears two prominent horns (Fig. f7ii). The larva lives within the fungi referred to above. The Pinacate-bugs (Pin-ah-cah'te-bugs). — Sev- eral species of Eleodes (El-e-o'des) are abundant on the Pacific coast, where they are found under IG 7"' stones and pieces of wood lying on the ground. They are apt to congregate in large numbers under a single shelter, and are clumsy in their movements. They defend themselves when disturbed by elevating the hinder part of i meas- I 584 THE STUDY OF INSECTS. the body and discharging an oily fluid from it. They present an absurd appearance, walking off clumsily, and carrying the hind end of the body as high as possible. The most common species are large, smooth, club-shaped beetles (Fig. 712), and are commonly known as Pinacate-bugs. These beetles and those belonging to several closely allied genera are wingless. The family yEGIALITID^: (^E-gi-a-lit'i-dae) was founded upon a single species from Alaska; recently another has been found in California. FIG. 712. The family ClSTELlD^E (Cis-tel'i-dae) in- cludes about fifty North American species, some of which are quite common. These are brownish beetles, without spots, which are found on leaves and flowers and under bark. The body is usually elongate, elliptical, and quite convex. They are most easily distinguished from allied families by the tarsal claws being pectinate, and the anterior coxal cavities closed behind. The larvae of some of our species at least live in rotten wood and resemble wire-worms in appearance. The family OTHNIID^; (Oth-ni'i-dae) is represented in our territory by four species of Othnius (Oth'ni-us), one from the East and three from the far West. They are small beetles, which are found running actively on the leaves of trees, and are probably predaceous. In this family the an- terior coxal cavities are closed behind, and none of the ab- dominal segments are grown together on the ventral side. The family LAGRIID^E (La-gri'i-dae) includes only five North American species, all of which are from the East, and are found under bark and on leaves. They are elongate beetles, with a narrow, subcylindrical prothorax, and a more or less brassy color. Our most common spe- cies is Arthromacra cenca (Ar-thro-ma'cra ae'ne-a). This species is nearly half an inch in length (Fig. 713). The family MONOMMID.E (Mo-nom'mi-dae) is rep- FIG. 713. resented in this country by a single genus, including four CGLEOPTERA. 585 species. They are small, black, oval, heteromerous beetles, in which the anterior coxal cavities are open behind ; and in which the antennae are received in grooves on the under side of the prothorax. The family MELANDRYID.E (Mel-an-dry'i-dae) includes about sixty North American species. These are found under bark and in fungi. They are usually of elongate form, al- though some, like the one figured here, are not so. The maxillary palpi are frequently very long and much dilated ; and the first segment of the hind tarsi is always much elongated. Among our more common species are two belonging to the genus PcntJie (Pen'the). These are rather large, oval, de- pressed beetles, upwards of half an inch in length, and of a deep black color. Pentlie obli- FIG. 7i4. quata (P. ob-li-qua'ta) is distinguished by having the scutel- lum clothed with rust-red hairs (Fig. 714). Pentjie pi melia (P. pi meFi-a) closely resembles this species, except that the scutellum is black. The family PYTHID^E (Pyth'i-dae) includes less than a score of North American species. Some of these live under bark; others are found under stones. They are heteromer- ous beetles, in which the anterior coxal cavities are open behind, the head is not strongly and suddenly constricted at base, and the prothorax is not margined at the sides. The family CEDEMERID.