Chapter VIII: Hemiptera, or Bugs—anoplura 532 (24)

PARALLEL SERIES.—In certain cases individuals of one generation assume different habits, and so set up the phenomenon known as parallel series. This has been recently investigated in the genus _Chermes_ by Blochmann, Dreyfus, and Cholodkovsky. This latter savant informs us[525] that a wingless parthenogenetic female of _Chermes_ hibernates on a fir-tree—_Picea excelsa_—and in the spring lays numerous eggs; these hatch, and by the effects of suction of the _Chermes_ on the young shoots, galls are formed (Fig. 286), in which the Insects are found in large numbers; when they have grown the galls open, and allowing the Insects to escape these moult and become winged females. They now take on different habits; some of them remain on the _Picea_, lay their eggs thereon, and out of these there are produced young that grow into hibernating females, which next spring produce galls as their grandmothers did; but another portion migrates to the Larch (_Larix_); here eggs are laid, from which proceed wingless parthenogenetic females, that hibernate on their new or secondary plant, and in the following spring lay their eggs and give rise to a dimorphic generation, part of them becoming nymphs and going on to the winged condition, while the other part remain wingless and lay eggs, that give rise to yet another wingless generation; in fact, a second pair of parallel series is formed on the new plant, of which one is wingless, and exclusively parthenogenetic, and continues to live in this fashion for an indefinite period on the secondary plant, while the other part becomes winged; these latter are called sexuparous, and go back to the _Picea_, and there lay eggs, that give rise to the sexual forms. If we would summarise these facts with a view to remembering them, we may say that a migration of a part of a generation from the _Picea_ was made with a view of producing a sexual generation, but that only a portion of the migrants succeeded in effecting the object of the migration, and this only in their third generation. Thus portions remained on the _Picea_, {587}producing unisexual (female) individuals, and a portion of those that emigrated to the _Larix_ remained thereon, producing also unisexual (female) individuals, while the others returned to the _Picea_ and produced a sexual generation. How long the production of the unisexual generations may continue has not been determined.

_Phylloxera._—The _Phylloxera_, that has caused such an enormous amount of damage in the Old World during the last thirty years, is a small Aphid that was introduced from North America into Europe. In North America it is not so injurious as it is in Europe, owing, no doubt, to slight distinctions in the conditions of life in the two hemispheres, as one of which may be mentioned that in Europe a larger proportion of the individuals produced appear to confine themselves to feeding on the roots, _P. vastatrix_ being one of the species that lives both in galls on leaves, and underground on the roots. The species is one that exhibits in their most complex form the peculiar phenomena of Aphid life we have already mentioned. It has probably only one congener, _Phylloxera quercus_, and of this Lichtenstein says that in its cycle, from the starting-point of the winter-egg to the assumption of the sexual condition, it exhibits a series of no less than twenty-one forms.[526] The life of _Phylloxera vastatrix_ apparently differs essentially from what we have described in _Chermes_, inasmuch as the migrations are only between leaf and root of the same plant—the vine—and not from one species of plant to another. Some authorities treat _Phylloxera_ and _Chermes_ as a separate family under the name of Phylloxeridae.

_Galls._—Like _Phylloxera_, many species of Aphidae live partially, others wholly, in galls that are produced by plants as the result of one or more Aphids interfering with a delicate part of the plant when it is in a young and growing state. The usual position of Aphid galls is on a leaf or leaf-stalk. But in the case of the genus _Chermes_, {588}a bud or some growing part of the spruce-fir is affected in such a way that it gives rise to an object having externally the appearance of a little fir-cone, while inside it consists of chambers in which the Aphids reside. The forms of Aphid-galls are very diverse, but this is probably due to the plant rather than to the Insect, for the same species of Aphis may give rise to different forms of galls. Réaumur thought that each Aphid-gall was due to a single individual that irritated the tissue of the plant, so that the latter grew up at the point of irritation and enclosed the Insect.

A few points as to the anatomy of Aphids should be noticed. It is doubtful whether the antennae have ever really more than six joints, the apparent seventh joint being actually a sort of appendage of the sixth. The rostrum is externally three-jointed, and is remarkable for the great diversity in its length, sometimes it is quite short, at others several times longer than the body (Fig. 285); the setae are often very much longer than the sheath; in cases where this great length of rostrum exists, the individual may often be found with the tip firmly fixed in the bark, and, as it were, tethered by means of the rostrum, the length of which allows, nevertheless, considerable locomotion. Suction is performed by contractions of the pharynx. There has been much difference of opinion as to whether there is a salivary syringe, and Witlaczil failed to find it. Krassilstschik is, however, positive that it exists,[527] and that it is analogous to that described by Mayer in _Pyrrhocoris_, but there are great differences of structure between the two. It is very difficult to determine the number of segments at the extremity of the body; this is terminated dorsally by a median organ placed above the anus, and known as the cauda. Balbiani apparently considers that there are ten abdominal segments and the cauda. The alimentary canal has a small stomach, and an elongate intestine, the terminal division of which is capacious and remarkably long. There are no Malpighian tubes; according to Kowalevsky, their function is discharged by the posterior part of the alimentary canal. There exists, however, a peculiar structure, the pseudovitellus, a sort of cellular, double string; and Witlaczil, in his valuable paper[528] on the anatomy of Aphidae, suggests that this {589}organ may in some way replace the missing Malpighian tubes. Another highly peculiar structure is the siphons, frequently called nectaries, honey-tubes, or siphuncles. They are situated on the dorsal aspect of the fifth abdominal segment, but exist only in certain of the sub-families; they are of very different lengths according to the species, and are capable of movement; they open directly into the body cavity, though exceptional openings into the body cavity are extremely rare in Insects. They excrete a waxy matter, which first appears as oil-like globules. It was formerly supposed that they were the means of secreting the sugary matter, called honey-dew, so much prized by ants and some other Insects; but this is now ascertained to be erroneous. This matter comes from the alimentary canal, and is secreted in large quantities by some species, Büsgen having observed that forty-eight drops, each about 1 mm. in diameter, were emitted by a single individual in twenty-four hours.[529] Certain gall-dwelling Aphidae—_Pemphigus_, _Chermes_ (Fig. 285), _Schizoneura_—possess numerous wax glands; these seem to replace the siphons, and excrete the peculiar, whitish flocculent matter that is so conspicuous in some of these Aphids.

Earlier anatomists failed to find any dorsal vessel, and it is consequently reported in books to be absent. It has been, however, recently detected by Witlaczil, and Mordwilko states that it does not differ from that of other Insects.

We have already alluded to the fact that the mode of reproduction of Aphids leads to an unrivalled increase. This, however, is not due to the prolificness of the individual, which, in point of fact, appears to be considerably below the average in Insects, but rather to the rapidity with which the young begin to reproduce. This has been discussed by Huxley, Buckton, and others. The first-named naturalist calculated that the produce of a single _Aphis_ would, in the course of ten generations, supposing all the individuals to survive, "contain more ponderable substance than five hundred millions of stout men; that is, more than the whole population of China."[530] It has since been contended that Professor Huxley's calculation was much below the mark. Although it is somewhat difficult to make a calculation dealing adequately with the actual facts, yet it is clear that the increase {590}of Aphids is such that, drawing as they do their nutriment directly from the plant in its growing state, in the course of two or three years there would be no nutriment available for other animals, except such as might be derived from plants not attacked by Aphids. The numbers of Aphidae would be so great that they could not be expressed by ordinary numerical methods, and their increase would be actually limited only by the relations existing between different kinds of plants, and between plants and Aphids. This result is avoided by the fact that Aphids are themselves the victims of a whole army of Insect enemies. They have the numerous members of a special group (Braconidae, Aphidiides) of minute Hymenoptera to live inside their bodies, and many Aculeate Hymenoptera depend entirely on the Aphidae as the source of food for their own progeny. The Lady-birds—Coccinellidae—live on Aphids and Coccids, and themselves increase to such an extent as to be in many years a conspicuous part of the Insect world. Crowds of the larvae of Hemerobiids and Syrphids are constantly engaged in spearing and sucking the Aphides. Hence the old naturalist Bonnet said that, just as we sow grain for our benefit, Nature has sown Aphids for the benefit of multitudes of different Insects. He might have added that these different Insects are for the benefit of man, it being clear that without them the population of the world must rapidly decrease.

Ants treat Aphidae more intelligently than most other Insects do, for they do not destroy the helpless creatures, but utilise their products in the way man does those of the cows he keeps. The relations between ants and Aphids is itself an extensive chapter in Natural History; many facts have been brought to light showing that the ants manage the Aphids in a prudent or intelligent manner, distributing them when too numerous in one place, keeping guard over them, even building shelters for them, and in some cases keeping them in direct association, by retaining the Aphids in their own dwellings. The further investigation of these points goes, the more it tends to raise the actions of the ants to the level we call in ourselves intelligent. It would even appear that the ants are acquainted with the migrations of the Aphids from one species of plant to another, Webster informing us that as the Aphis-population on an apple tree multiplied the ants in attendance anticipated their migration to wheat and grass {591}by carrying them to those plants.[531] We have nearly 200 species of Aphidae in Britain,[532] and there may perhaps be 800 known altogether. To what extent they may occur in the tropics is undetermined. There are said to be no native species in New Zealand.

FAM. 8. ALEURODIDAE.—_Minute Insects, with four mealy wings, seven-jointed antennae, two-jointed feet, terminated by two claws and a third process._ These minute Insects are at present a source of considerable perplexity, owing to the curious nature of their metamorphosis, and the contradictory accounts given of them. In the earlier stages they are scale-like and quiescent, being fixed to the under side of a leaf. The French authors Signoret and Girard state that the young are hatched having visible appendages and segmentation, but that after they are attached to the leaf the organs gradually suffer atrophy. Maskell states the opposite, saying that the organs in the earliest stages are not usually recognisable, but become faintly visible with the growth of the Insect. Heeger states that the larva undergoes three ecdyses, and he gives the figures we reproduce; if he be correct it would appear that the nymph undergoes a great development. Réaumur, on account apparently of their great metamorphosis, treated the species {592}known to him as being Lepidopterous, though he correctly pointed out their distinctions. At present we can only conclude that the Aleurodidae undergo a metamorphosis of a kind peculiar to themselves, and requiring renewed investigation. The family has been monographed by Signoret, and more recently by Maskell, who has increased the number of species to about sixty.[533] We have three or four in Britain, one of which, _A. brassicae_, is extremely abundant on various kinds of cabbage in certain years.

FAM. 9. COCCIDAE (_Scale-Insects_, _Mealy-bugs_).—_Insects, usually minute, with only a single claw to the foot; the male with one pair of wings, but without mouth-parts; the female wingless and usually so degraded in form that most of the external organs and appendages cannot be distinguished._ The form in which these Insects are most generally known is that of a small scale or shell-like body closely adhering to leaves, fruits, or bark. The scales are of the most varied form, so that no general description can be given of them. The scale may be defined as an accumulation of excreted matter, combined with the cast skin or skins of the Insect, covering the body either totally or partially, and thus acting as a shield under which the subsequent development takes place. All Coccidae do not form scales; but the habit of excreting a large quantity of peculiar matters to the outside of the body is universal; this excreted substance is frequently white, and of a powdery nature, and Coccids of this kind are known as mealy-bugs. In other cases the exudation is like shell or glass, and the creature may become quite encysted therein. In this way the forms of Cocidae known as "ground-pearls" are formed. When first hatched from the egg Coccidae are mite-like creatures, and it is only subsequently that the females lose the power of locomotion. The females of numerous forms of Coccidae—more particularly the mealy-bugs—do not lose the antennae and legs. There is also a group (Brachyscelides) of Coccids that live in {593}galls. This highly aberrant group is, however, peculiar to Australia; elsewhere very few gall-making Coccids have been discovered.

There are upwards of 800 species of Coccidae at present known.[534] The family was monographed by Signoret about twenty-five years ago, and since then there has been very much matter concerning them published in a scattered manner.[535] No general work has been published on the British species, but Mr. Newstead is preparing one. The classification of Insects so minute as Coccidae, and with such extreme difference in the sexes, is, of course, a matter of great difficulty; the best divisions are those given by Green in his _Coccidae of Ceylon_.[536]

The fact that there is only one pair of wings in the perfect male Coccid would appear to ally these Insects with the Diptera; these Coccidae have, too, like the Diptera, a small appendage on each side of the metathorax. Witlaczil shows that these little processes may really represent a pair of wings, inasmuch as they are developed from imperfect folds of hypodermis, _i.e._ imaginal discs. Beyond these facts and the occurrence in certain females (Margarodes) of a great histolysis during the post-embryonic development, there is nothing to indicate any relationship between Coccidae and Diptera. It has been shown by Riley that these little processes, in some forms, serve as hooks to attach or control the true wings, and this function is never assumed by the halteres of Diptera. Although Coccidae are placed next Aphidae, yet the two families appear to be really very different. The modes of reproduction so peculiar in Aphidae reappear to a certain extent in Coccidae, but are associated with profound {594}distinctions. Though the viviparous method of reproduction and parthenogenesis occur in Coccidae, yet they are only exceptional, and they are not put to the same uses by the species that exhibit the phenomena. Thus we have seen that in Aphidae generations of imperfect individuals are produced with rapidity, while the individual is not directly very prolific. In Coccidae the reverse is the case—the generations are usually similar to one another; they do not, as a rule, follow with rapidity, and the female is usually very prolific, thousands of young being sometimes produced by a single individual. The extraordinary polymorphism of the species of Aphidae is not exhibited by Coccidae, though, contrary to what we find in Aphidae, the males and females are usually excessively different. The two families apparently also differ in that Coccidae are specially characteristic of warm climates, Aphidae of the temperate regions.

PARTHENOGENESIS.—Owing to the fact that the males are very minute creatures, totally different from the females, and living but a very short time, they were but little known to the earlier observers. It was therefore only natural to suppose that parthenogenesis was very common. Of late years the males of a great many species have become known, so that ordinary sexual reproduction must be considered as the normal method in Coccidae, although, in the great majority of cases, the male is still unknown. It has, however, been shown in numerous cases that parthenogenesis may occur even when males exist; and there are some abundant species of which it has not been possible to find a male. In 1887 Moniez[537] announced that he had discovered the male of _Lecanium hesperidum_ (one of the notoriously parthenogenetic species) in an ovarian cul-de-sac in the body of the female, and he therefore considers that sexual reproduction occurs. He does not say how pairing takes place, and we are not aware that his observation has been confirmed. If correct it will be necessary to reconsider the whole question as to parthenogenesis in Coccidae. Apterous males are known in two or three species.

The post-embryonic development of Coccidae is of the most unusual character. It is quite different in the two sexes, and in each of them it presents features not found elsewhere. It has, however, as yet been studied in only a few forms, and even in them is incompletely known.

{595}

When hatched from the egg the young Coccids are all similar, male and female being indistinguishable. A difference soon appears, with the result that the male, after passing through more than one pupal condition, appears as a winged Insect. The female never becomes winged, but, if we may judge from the incomplete accounts we at present possess, her development varies much according to species. In some she retains the legs, antennae, and mouth-organs; in others she loses these parts, though retaining the original form in a general manner; while in a third (_Margarodes_) she becomes encysted, and apparently suffers an almost complete histolysis, reappearing after a very long period (it is said it may be as much as seven years) in a considerably altered form. The post-embryonic development of _Aspidiotus nerii_ has been studied by Schmidt[538] and Witlaczil,[539] whose accounts agree except as to some points, such as the number of ecdyses. The young, or larva, is hatched with fairly well-developed legs, antennae, and rostrum; there is no external difference between the sexes. The larva selects some spot on the plant and drives its rostrum therein, thus becoming fixed; moults occur, and the body excretes waxy matter from its sides in processes that fell together and form the shield; the female becomes much larger than the male. The legs and antennae of both sexes disappear, so that the power of movement is completely lost. The mouth-parts also atrophy. The female after this undergoes no further change, except that of growth in connection with ovarian development.

{596}

The male, however, continues development; notwithstanding the impossibility of taking food, owing to the absence of a mouth, it increases much in size, and the organs of the future perfect Insect commence to develop from imaginal discs in a manner similar to that which occurs in the Dipterous genus _Corethra_; no mouth-parts are however developed, these being merely represented by spots of pigment, or rudimentary additional eyes. The wings are developed outside the body. Difference of opinion prevails as to the nature of the instars between the young larva and the imago. It is clear, however, that Fig. 291, D, corresponds fairly with the pupa of Insects with complete metamorphosis, and the instars shown in Fig. 291, B, C, may therefore be looked on as equivalents of the resting-larva stage of ordinary Insects with complete metamorphosis. Witlaczil considers this development to be a condition of incomplete, approaching very nearly to complete, metamorphosis. The condition is perhaps more precisely estimated if we recollect that winged Insects are divided into two series, in one of which the wings are developed outside the body; in the other, inside the body. The Insects with very complete metamorphosis all belong to the second of these two series, while in the male Coccid we have the highest form of metamorphosis attained by any of the first series. As regards the development of the female encysted nymph or pupa, previously alluded to as being found in the "ground-pearls" of {597}the genus _Margarodes_, we can at present offer the reader no satisfactory account.[540]

PRODUCTS OF COCCIDAE.—Honey-dew is secreted by Coccidae, but as a rule not so extensively as by Aphidae and some other Homoptera; nevertheless, it is often sufficient to make the plants frequented by Coccids very sticky and unclean. Some species make a really extensive exudation of such matter. Réaumur records that a Coccid, which is doubtless _Lecanium persicae_, excretes a supply of honey-dew that drips to the ground; he says it tastes sweet and nice. The manna mentioned in the book of Exodus is pretty certainly the honey-dew secreted by _Coccus_ (now _Gossyparia_) _mannifera_, which lives on _Tamarix_ in many places in the Mediterranean basin. This substance is still called by the Arabs "Man," and is used as food; in its natural state it is a substance very like honey; it is doubtless excreted by the _Coccus_, and is not produced directly by the _Tamarix_ as some have supposed. Waxy matters are produced by several Coccidae. _Ceroplastes ceriferus_, a Lecaniid, produces white wax in India. _Ceroplastes_ is a widely distributed genus, and various species of it have been used for the purpose of producing wax in other parts of the world. The white wax of China is understood to be produced by another Lecaniid, _Ericerus pela_; but little is known as to this Insect; it is said that the wax is produced by the winged males. The substance was formerly greatly prized in China, but is falling into disuse on account of the introduction of Kerosene. Lac is produced by _Carteria lacca_, a Lecaniid living in India on _Anona squamosa_, as well as on species of _Ficus_, _Rhamnus_ and other trees; the lac is the shelly scale produced by the Insect as a covering; it is composed in larger part of resinous matter, with which there is mixed a comparatively small quantity of wax and other substances. The body of this Insect also affords the red substance called lake. Various species of _Kermes_ formerly afforded a red dye well known to the Greeks and Romans. These Insects live on _Quercus coccifera_ in the Mediterranean region. A medicinal syrup is also obtained from them. _Porphyrophora polonica_ was used in North and Central Europe for the same purposes as _Kermes_; it is a Coccid living on the roots of _Polygonum cocciferum_. These European Insects were replaced commercially {598}after the discovery of America by the cochineal Insect, _Coccus cacti_, a Mexican Coccid feeding on a Cactus called Nopal (_Opuntia coccinellifera_). This Insect was subsequently introduced to the Eastern hemisphere, and was established with more or less success in a few spots on the borders of the Mediterranean. In the Canary Islands it flourished on other species of _Cactus_, became acclimatised, and was the object of an extensive commerce. The colour in the case of all these Coccid dyes was obtained from the bodies of the Insects, in the tissues of which it is contained. The dyes have now been largely displaced in commerce by the derivatives of Aniline. Axin is produced by the Mexican Coccid _Llaveia axinus_; this substance appears to be of a very peculiar nature; it is apparently chiefly fatty, and contains a peculiar acid, axinic acid. Axin is used as an external medicinal application in various affections; and it is also employed as a varnish; it dries and hardens on exposure to the air, and is said to be of considerable value.[541] In our British genus _Orthezia_ the body of the female is completely covered with a symmetrical snow-white armour, from which project the pink legs and antennae. This is one of the forms in which the female preserves the legs to the end of her life. The objects called ground-pearls, already alluded to, have long been known in various parts of the world, and in the island of St. Vincent they are sufficiently large to be collected and strung for necklaces. These bodies are the encysted pupae of Coccids of the genus _Margarodes_; the cyst is said to be of chitin. _M. vitis_ commits serious ravages on the vines in Chili by sucking their roots, and it is probable that all the species are of subterranean habits; this would partially explain the fact that very little is known about the history of these pearls, though naturalists have been acquainted with them for many years.

The gall-making Coccids of the group Brachyscelides have only recently been at all investigated; the galls they give rise to are sometimes about a foot in length, and there appear to be numerous species and several genera in Australia; they are especially abundant on _Eucalyptus_ and Acacias. The females are highly remarkable from the variable conditions the legs assume, so that in some cases they may be described as biped Insects, the {599}hind legs remaining, though the others have atrophied.[542] Very little indeed is known as to these Insects. One of the most peculiar points of their economy appears to be that the galls giving rise to males are different from those producing females.

ANOPLURA or LICE.

_Small Insects with thin integument; entirely wingless, the three thoracic segments indistinctly separated; the head bearing in front a short tube furnished with hooks; from which tube there can be protruded another very delicate sucking-tube. Feet terminated by a single long claw._ The Anoplura, Pediculidae, or lice are disgusting Insects about which but little is known. The most contrary opinions have been expressed as to their mode of taking their nourishment, which is, without exception, the blood of Mammals; on the bodies of which they pass the whole of their life. It is a most difficult matter to examine their mouth; the best information on this point is given by Schiödte and Graber, but though these two authorities agree, their results are very incomplete, and do not warrant us in expressing a confident opinion as to the nature of the relationship between Hemiptera and Anoplura—a question that has been for long a moot one. The short tube furnished with hooks in front (Fig. 293, _d_) is considered to be the lower lip, and the tube inside is, it is suggested, a combination of the homologues of maxillae and mandibles; there is also what may be a labrum (_g_); and inside the head a framework, at any rate analogous to if not homologous with, the parts of this kind we have described as existing in Hemiptera. All the parts, with the exception of the basal tube or head of the beak, are of the most minute and delicate nature, so that it is difficult to see their form or comprehend their relations. It is evident that they are very different anatomically from the mouth-parts of Hemiptera; still there is {600}sufficient general resemblance to warrant the belief that the parts in the two may ultimately be shown to be also morphologically similar. If Meinert be correct, this view will, however, not prove to have any foundation. He considers that morphologically the mouth of the louse has no similarity to that of the bug; the protrusible parts in the former he considers to be modifications of epipharynx and hypopharynx; and the rod-like structures to be hypopharyngeal lamellae; and that they are thus totally different from the setae of bugs.[543] He considers Lice to be a distinct Order of Insects for which he proposes the name Siphunculata.

The alimentary canal and nervous system resemble those of Mallophaga more than they do those of Hemiptera. The oesophagus leads into a large stomach bilobed in front; at the posterior extremity of this there open the four Malpighian tubes, and behind these there is a well-marked small intestine. The nervous system consists of a cephalic ganglion and of three other closely approximated ganglia, the posterior one the larger. It remains doubtful whether or not the first of these three ganglia is the infra-oesophageal one.[544]

The species of lice, so far as known, are not numerous, some six genera and about forty species being all that are recorded; they occur on various kinds of mammals, including some that live in water. Seals have a genus, _Echinophthirius_, peculiar to them. Monkeys are specially liable to be affected by lice; the genus that chiefly occurs on them is _Pedicinus_, a very distinct one, in which there are only three instead of five joints to the antennae. Perhaps the most remarkable louse is _Haematomyzus elephantis_, that of the elephant; it has a long proboscis in front of the head. As a rule each species of louse is confined to one species of Mammalia, or to very closely allied forms. Man is said to be infested {601}by three species, _Pediculus capitis_, _P. vestimenti_ and _Phthirius inguinalis_; Meinert is of opinion that _P. capitis_ and _P. vestimenti_ are only one species, and Schiödte appears also to have thought this probable. Andrew Murray was of opinion that the heads of different varieties of men are infested by distinct varieties of _P. capitis_. His conclusion was chiefly based on examination of specimens preserved by Charles Darwin; it requires confirmation. Very little is known as to the life-history of the louse. Leeuwenhoek made himself the _corpus vile_ for an experiment, from which he concluded that the _Pediculus vestimenti_ is very prolific. That scientific men did not know whether the louse bites or sucks was formerly made the ground for a taunt. Schiödte has given an almost pleasing account of the way in which he settled this,[545] showing that the sucking action is beyond all doubt. Accounts of disease called Phthiriasis, attributed to lice, are to be found in many old books, but the evidence does not warrant us in believing anything more than that persons suffering from some disease, and in a neglected and filthy condition, were horribly infested with these disgusting Insects.

It is usual to say that Pediculidae are Hemiptera degraded by a long exclusive persistence in parasitic habits. At present, however, this must be looked on as a pious opinion, rather than as an induction from our knowledge of their morphology and embryology; for this is at present too imperfect to warrant any final conclusion.

{602}NOTES AND CORRIGENDA

VOL. VI.

Note to P. 4: _Classification of Hymenoptera._ Mr. W. Ashmead has published[546] a sketch of a new classification of Hymenoptera, in which the points we have suggested are given effect to; the first division of the Petiolata being carried out with reference to the position of the ovipositor, while part of the Proctotrypidae is brought into the Aculeate division. We cannot, however, commend this arrangement as final, for several points have not received sufficient consideration.

Note to P. 172, line 22. For the words "We shall subsequently see," substitute "We have previously said" (p. 161).

Note to P. 350, line 10 from bottom: _instead of_ "only one genus," _read_ "only one Old World genus."

Note to P. 541, line 16: _instead of_ "two" _read_ "ten."

VOL. V.

P. 217, line 4. _For_ sterna _read_ nota.

P. 271. The lettering of Fig. 158 is erroneous; under the lower pointing line the letter d should be inserted, and the left hand upper pointing line should bear the letter c _instead of_ d.

P. 277, line 7. _Instead of_ Fig. 162, _read_ Fig. 163; and line 9, _instead of_ Fig. 163 _read_ Fig. 164.

P. 378. The species figured has since been described by Mr. Haviland as _Termes malayanus_.

P. 380. The species figured has since been described by Mr. Haviland as _Termes mirabilis_.

P. 383. _Hodotermes japonicus._ It has been recorded (_P. Boston Soc._ xii. 1869, p. 139) that this is not a Termite, but an immature form of the earwig _Brachylabis maritima_.

Pp. 480 and 481. It is not made clear that the distinction in the number of joints of the palpi of Phryganeides and Limnophilides applies to the males only; in both groups the number of joints in the females is five. The remark as to Phryganeides occurring in the Southern Hemisphere is erroneous. It is Limnophilides that reappear in Chili, not Phryganeides.

P. 490. Fig. 333 A, _f_ and its line point to a division of the mesonotum, not of the metanotum.

P. 564. Habits of _Pelecinus_. Mr. S. A Forbes has recorded an observation suggesting that _P. polyturator_ may be a parasite of Lamellicorn beetles of the genus _Lachnosterna_. See _Rep. Ins. Illinois_, xix. 1896, p. 79.

{603}INDEX

Every reference is to the page: words in italics are names of genera or
species; figures in italics indicate that the reference relates to
systematic position; figures in thick type refer to an illustration; f. =
and in following page or pages; n. = note.

Abdomen, of _Chrysis_, 2;
of Coleoptera, 185;
of Diptera, 446;
of Hemiptera, 538;
of Lepidoptera, 313;
of Thysanoptera, 528
Abdominal legs, 9
Abeille-perce-bois, 33
Abeille tapissière, 51
_Abispa_, 77
_Acacia fistulosa_, beetles in, 213
Acalyptrate Muscidae, _494_
_Acanthia_, _560_
Acanthomeridae, 483
_Acanthosoma griseum_, 546
Acari, relations to Insects, 220, 223, 238, 530
_Acentropus_, 425
Acephalous larvae, 449
Achreioptera, _219_
Acraeides, 350
_Acridium maroccanum_, 254
_Acrocera globulus_, 490
Acroceridae, 489
_Acronycta_, 418
_Actias luna_, 374
Actiidae, _510_
Acutilingues, _20_
Adapted excrement, 284, 284, 380
_Adelops_, 221
Adensamer, on _Ascodipteron_, 520
Adephaga, _190_, 200 f., _216_, _234_
Adimeridae, 240
_Adimerus setosus_, 241
Adlerz, on _Formicoxenus_, 160;
on _Tomognathus_, 161
Adminicula, 327
_Aëdes_, 455 n.
_Aegeria_, 387
Aegeriidae, 386
Aegialitidae, 265
_Aegocera tripartita_, 411
_Aenictus_, 159, _179_, _180_
_Aenigmatias blattoides_, 495
_Aeolothrips fasciata_, 528
Aëpophilidae, 559
_Aëpus_, 206
Aërostatic setae, 408
Aërostats, 449
Aganaidae, 408
Agaristidae, _370_, _371_, 410
_Agdistes_, 426
Agdistinae, _426_
_Agenia carbonaria_, _A. hyalipennis_, 105
_Ageronia_, 354
_Aglycyderes setifer_, 298
Aglycyderidae, 297
Agromyzidae, _504_
_Agrotis_, 415;
_A. spina_, 417
Ahuatle, 504
_Alaena_, _350_
_Alaopone_, 179, 180
Alar organs—see Wings, Elytra, Tegmina
_Aletia xylinae_, 416
_Aleurodes brassicae_, 592;
_A. immaculata_, 591
Aleurodidae, 591
_Alucita_, _426_;
_A. polydactyla_, 426
Alucitidae, 371, 426.
Alula, 447
_Amara_, 205
Amber, Insects in, 144, 269, 458
_Amblyopone_, 180
Amblyoponides, 132, 180
Ambrosia, 295
_Ambryllis_, 409
_Amicta quadrangularis_, 394
_Ammophila_, 111;
_A. affinis_, 111;
_A. hirsuta_, 111;
_A. holosericea_, 111
Amphicyrtides, _242_
_Amphidasis betularia_, 412, 414
Amphiodont, 193
Amphipneustic, 450
_Amphizoa lecontei_, 207
Amphizoidae, 207 {604}
_Ampulex compressa_, 114, 115;
_A. ruficornis_, 115;
_A. sibirica_, 114
Ampulicides, 114 f., 169
Amycterides, 291
Anal armature, 328, 416
Anal nervures, 318
_Anaphe_, 376
Anaspini, 267
_Anaspis_, 268
Anatomy—see External Structure and Internal Anatomy
Anchor-process, 459
Ancient, Lepidopteron, 435—see also Primitive
Ancylolominae, _425_
_Andrena_, _23_, 25, 30, 301, 303;
hair of, 11;
_A. labialis_, 488;
_A. nigroaenea_, 23;
_A. ovina_, 30
Andrenidae, _20_
Andrenides, 23
_Andrenimorpha_, 388
Andrenoides, _20_
Androconia, 331 f.
_Anergates atratulus_, 160 f.
Angelitos, 63
_Anisopteryx aescularia_, 411
_Anisotoma cinnamomea_, 222
Anisotomidae, _223_
Anisotomides, 222
Anlagen, 143
Anobiides, 247
_Anobium_, 254;
_A. paniceum_, 247;
_A. striatum_, 248;
_A. tessellatum_, 248
_Anochetus ghiliani_, 174
_Anomma_, 178
_Anophthalmus_, 205
Anoplura, 599 f.
_Anosia erippus_, _A. menippe_, 345;
_A. plexippus_, 307;
larva, 324;
pupa, 327
Antennae;
of _Belostoma_, 566;
of flies, 441;
of Lamellicornia, 191;
of Lepidoptera, 307;
of butterflies, 340, 341;
of Sphingidae, 380
_Antherophagus_, 235
Anthicidae, 266
_Anthidium_, 45;
_A. bellicosum_, 47;
_A. diadema_, 45;
_A. manicatum_, 45;
_A. septemdentatum_, 47;
_A. strigatum_, 30
_Anthocopa_, 51
Anthocoridae, _560_
_Anthomyia angustifrons_, _A. brassicae_, _A. cana_, 506
Anthomyiidae, 506
Anthophila, 10 f.
_Anthophora_, 32, 33;
destroyer of, 272, 274;
_A. personata_, 33;
_A. pilipes_, 33;
proboscis of, 17
_Anthothrips aculeata_, 530
Anthracides, 486
_Anthrax_, 486 f.;
_A. fenestralis_, 489;
_A. trifasciata_, 44
_Anthrenus fasciatus_, 241
Anthribidae, 278, 290
Antisquama, 448
Antitegula, 447
Ant-plant, 138, 139, 168
Ants, 131 f.;
and Aphidae, 590;
and caterpillars, 356
Ants'-nest, Insects, 200, 213, 221, 223, 224, 225, 231, 236, 240, 548;
larva, 501, 502
Anus, 314, 320
Aorta, 320
Aortal chamber, 320
_Apate capucina_, 246
_Apatela_, 418
_Apathus_ = _Psithyrus_, q.v.
Apatidae, 246
_Apatura_;
larvae, 354;
_A. iris_, 344
Apaturides, 352
_Aphaenogaster_, 164, 165, 221;
_A. arenarius_, 164;
_A. barbarus_, 131, 164;
_A. structor_ 164, 240
Aphaniptera, 522 f.
_Aphanocephalus_, 228
_Aphelocheirus_, 565
Aphidae, 581 f.;
and ants, 181
Aphidiides, 590
_Aphis maidi-radicis_, 584
_Aphomia sociella_, 424
Apidae, 10 f., 20, _32_
Apioceridae, 492
_Apis_, _53_;
_A. adansonii_, 69;
_A. domestica_, 68;
_A. dorsata_, 69;
_A. fasciata_, _A. ligustica_, 68;
_A. mellifica_, 65 f.;
feet of queens and workers, 69;
ligula of, 16;
worker and hairs, 12
_Apoda_, 402;
_A. testudo_, etc., 401, 402
Apodidae, 402
_Apoica pallida_, nest, 83
_Aporia crataegi_, 322
Appetite, 491
_Apterogyna_, 96
_Apterona_, 393, 394;
_A. crenulella_, var. _helix_, 395
Apterous, beetles, 187, 263;
females, 95, 96, 140, 171, 174, 315, 392, 393, 407, 413, 430, 592—see
also Workers;
Insects, 95, 96, 474, 495, 496, 505, 518, 531, 581;
males, 140, 160, 161, 172, 585, 594
Aquatic;
caterpillar, 377;
cocoons, 280;
larva, 421 f., 425, 504;
pupa, 423
Aradidae, 550
_Aradus orientalis_, 550
_Araeocerus_, 290
_Araschnia levana_, _A. prorsa_, 353
Arbelidae, _369_, 396
_Arceina_, 373
Archiapidae, _21_, _22_
Archiapides, _21_ f.
_Arctia caja_, 308;
_A. villica_, 410
Arctiidae, _370_, _404_, 408, _410
Argiva_, 414 {605}
_Argynnis_, larvae, 354;
_A. paphia_, androconia, 332
_Argyromoeba sinuata_, 76;
_A. trifasciata_, 486
Arista, 442
Army-worm, 416
_Aromia moschata_, 188
_Arthropterus_, 214
_Asclera caerulea_, 267
_Ascodipteron_, 520
_Asemorhoptrum lippulum_, _160_
Asilidae, 491
_Asilus_, 492;
_A. crabroniformis_, 441
Asparagus-beetle, 281
_Aspidiotus camelliae_, 592;
_A. nerii_, 595, development of, 596
_Aspidiphorus_, 246
_Aspidomorpha_, pupa, 283, 284
Association, of _Anergates_ and _Tetramorium_, 160;
of ants and other Insects etc., 180 f.;
of _Formica_ and _Formicoxenus_, 159;
of _Strongylognathus_ and _Tetramorium_, 162;
of _Tomognathus_ and _Leptothorax_, 161
_Astata boops_, 119
_Astatides_, 119
Asteidae, _504_
_Astomella lindeni_, 490
_Astynomus_, 285
_Atemeles_, 225;
and ant, 182
Athericerous, 441
_Atherix_, 481;
_A. ibis_, 480
_Athous rhombeus_, 257
_Atractocerus_, 254
Atrophy of mouth and stomach, 310
_Atta_, 137, 164 n., 165, 502
_Attacus_, 373;
_A. atlas_, 373
Attelabides, 291
Attini, 158, 159, 165
Attitude, 381, 384, 385, 388, 412, 413, 425, 429
_Atylotus fulvus_, 483
_Autocrates aenea_, 275
_Automeris_, 373
Axin, 598
_Azteca_, 158
Azygos oviduct, 321

_Badamia exclamationis_, 365
Barrett, on increase of melanism, 414
Basket-worms, 393
Bat-parasites, 521, 560
Bataillon, on metamorphosis, 306
Bates, H. W., on classification of butterflies, 344;
on homoeochromatism, 351;
on _Megacephala_, 201
Batesian mimicry, 337, 339
_Bathyscia_, 221
Beak, 532
Beauregard, on vesicating Insects, 275
Beaver, Insect on, 219, 221
Becher, on mouth of Diptera, 444 n.
Bed-bug, 559;
enemy of, 558
Beddard, on animal coloration, 339 n.
Bee (_i.e._ honey-bee)—see _Apis mellifica_
Bee-louse or -tick, 520
Bees, 10 f.
Bees born of carcases, myth, 499
Bees' nest beetle, 235
Bees, stylopised, 300, 303
Beetles, 184 f.
Bellesme, on buzzing, 19
Belostomidae, 534, 565
Bembecidae, 482
Bembecides, 119 f.
_Bembex_, 509;
_B. rostrata_, 4, 120, 120 f.;
_B. spinolae_, 130 n.
Benchucha bug, 559
_Berosus_, 218
Berytidae, 548
_Bibio_, 475, 476, 477;
_B. marci_, 477
Bibionidae, 475
Birds and butterflies, 338
Biscuit-weevil, 247
_Bitoma crenata_, 233
_Bittacomorpha_, 473
Black-fly, 530
Blanchard, on flies attacking man, 517 n.
Blepharoceridae, 464
Blind beetles, 205, 221, 233
_Blissus leucopterus_, 548
Blister-beetles, 269
Blochmann, on founding new nests, 145
Blood-sucking, Diptera, 457;
Mosquitoes, 467
Blood-worms, 468
Blow-flies, 511
Blue-bottles, 511
Bogus Yucca-moth, 433
_Boletophila luminosa_, 463
Boll-worm, 416
Bombardier-beetles, 201
_Bombus_, 53 f.;
insect in nest of, 221;
fleas in nests of, 525;
parasite of, 94, 497;
proboscis of, 13 f., 14;
_B. agrorum_, 54;
_B. lapidarius_, 54;
_B. muscorum_, 57;
_B. variabilis_, 60
Bombyces, _367_
Bombycidae, _368_, 375, 406
Bombyliidae, 485
_Bombylius major_, 488
_Bombyx mori_, 375;
_B. yamamai_, 325
Book-worm, 247
Borboridae, _504_
_Borborus_, 505
_Borocera madagascariensis_, 405
Bostrichidae, 246
Bot-flies, 514
Brachelytra, _224_
Brachycera, 441, 454
Brachycerides, 291
Brachyscelides, 592, 598
_Brachytarsus_, 290
Braconidae, 590 {606}
_Bradypus cuculliger_, Tineid on, 430
Brahmaeidae, _368_, 374
Brain, 320;
cephalic and thoracic, 449
Branchiae, 208, 244
Brands, 332
Brassolides, 349
_Brathinus_, 223
Brauer, on Dipterous larvae, 451;
on Oestridae, 514
_Braula coeca_, 520
Braulidae, 520
Breastbone, 459
Breeze-flies, 443, 481
Breitenbach, on proboscis of Lepidoptera, 311 n.
Breithaupt, on proboscis of bee, 15;
on deglutition of bees, 18
Brenthidae, 295
_Brenthus anchorago_, 297
_Brephos notha_, 415, 416
Brimstones, 357
_Brontes planatus_, 234
Brown-tail moths, 407
Bruchidae, 276
_Bruchus fabae_ and _B. lentis_, 277, _B. pisi_, 277
_Bryophila_, 418
Buckell, on development of pattern, 335
Buffalo-gnats, 477
Bugong-moth, 417
Bugonia-myth, 499
Bull-dog ants, _171_, 173
Bull's-horn thorn and ants, 168
Bumble bee—see _Bombus_
Buprestidae, 261
_Buprestis attenuate_, supposed larvae of, 262 n.
Burgess, on suction, 311
Burnet-moths, 390
Burrows, of _Dasypoda_, 27;
of _Halictus_, 24, 25;
of _Odynerus_, 74
Bursa copulatrix, 321
Burying-beetles, 221
Butterflies, _341_ f.
Buzzing, 19
Byrrhidae, 242, _255_
_Byrrhus pilula_, 242
Bythoscopidae, 578
_Byturus_, _241_

_Cadphises moorei_, 391
Calandrides, 289
Calcium oxalate, 406
_Calicurgus_, 101;
_C. hyalinatus_, 102, 106
_Caligo eurylochus_, 350
_Callidea baro_, 303 n.
Callidulidae, _370_, 400
_Calliphora_; 448;
_C. erythrocephala_, _C. vomitoria_, 511
_Callirhipis dejeani_, 256
_Callomyia_, 496
_Callostoma fascipennis_, 489
_Caloptenus_, 270;
_C. italicus_, 489, _C. spretus_, 488, 506, enemies of
Calypter, calypterate, 448
Calyptrate Muscidae, 448, _504_
Camberwell Beauty, _352_
Camel bot-fly, 515
Camponotides, 144
_Camponotus_, 145;
_C. ligniperdus_, 138, 145, 147;
_C. pennsylvanicus_, 138, 146;
_C. rubripes_, 131;
_C. rufipes_, 137
Camptosomes, _279_, 281
Canephorinae, 394, 395
Cantharidae, 269 f.
Cantharides, _270_
Capsidae, 561
_Capsus laniarius_, 539
Carabidae, 204 f.
Carabides, _206_
Caraboidea, _190_, 200 f.
_Carcinocoris_, 554
Carder-bees, 45 f., 45
_Cardiocondyla_, 161
_Cardiophorus_, 258
Carlet, on sting, 6;
on sound-organs of _Cicada_, 574
Carnivora, _200_
Carotine, 549
Carpenter-bees, 33
Carpenter-worms, 395
Carpets, 411
_Carpocapsa juliana_, _C. pomonella_, _C. splendana_, _C. saltitans_, 428
_Carpophagus_, 278
_Carteria lacca_, 597
Carus, on paedogenesis, 461
_Caryoborus_, 278
Case, 281, 392, 393, 394, 417, 422, 423, 430, 431
Cassidides, _279_, 283
Caste-production, 142
_Castnia_, 307, 309, 316, 319;
_C. eudesmia_, _C. therapon_, 372
Castniidae, _369_, 371
_Castor canadensis_, parasite of, 219
_Cataclysta lemnata_, 423
Caterpillar, 322, 324, 325;
of Diptera, 474
_Catopomorphus_, 221
Cauda, 538, 588
Cave-beetles, 205, 221
Cebrionides, _260_
_Cecidipta excoecaria_, 424
_Cecidomyia buxi_, 459;
_C. destructor_, 460;
_C. tritici_, 460
Cecidomyiidae, 455 n., 458
_Cecropia_, plant and ants, 158
_Cedeocera_, 297 n.
Cell, of wing, 317, 318;
complete and incomplete, 116 n.
Cells, formation of, by bees, 21, 22, 24, 25, 28, 33, 34, 35, 46, 48, 51,
52, 54, 56, 60;
earthen, 72, 106;
of _Coelonites_, 89
Celyphidae, _504_ {607}
_Celyphus_, 505
_Cemonus unicolor_, 128
Cephaloidae, 275
_Cephalomyia maculata_, 515
_Cephaloon_, 275
Cephalothorax, 465;
of _Stylops_-larva, 302
_Cephenomyia rufibarbis_, 517
Cerambycidae, _278_, 285
Cerambycides, _287_
_Ceramius_, _89_;
_C. lusitanicus_, 89
_Ceranchia_, 374
_Cerapachys_, _175_ n.
_Ceratina_, 11, _32_
Ceratocampidae, _368_, 375
Ceratocombidae, 559
Ceratognathini, 194, _195_
_Ceratonema_, 401
_Ceratopogon_, 469;
_C. bipunctatus_, _C. pulicaris_, _C. varius_, 470
_Cerceris_, 125;
_C. arenaria_, 125;
_C. bupresticida_, 125;
_C. labiata_, 125;
_C. tuberculata_, 126
Cercopidae, 577
_Ceresa bubalus_, _C. taurina_, 577
_Cerocoma schaefferi_, 275
Cerophytides, _260_
_Ceroplastes ceriferus_, 597
_Ceroplatus mastersi_, 463
_Cerura vinula_, 383
Cervical sclerites, 472
_Cetonia_, in ants'-nests, 149;
_C. floricola_, 200
Cetoniides, _195_, 199
_Chaerocampa_, 380; recte _Choerocampa_
Chaetophorous, 446
Chaetotaxy, 446
Chafers, 194 f.
Chalcosiidae, 391, _420_
_Chalia hockingi_, 394
_Chalicodoma_, 32, 35;
_C. muraria_, 30, 35 f., 36, 254, 486;
_C. parietina_, _C. pyrenaica_, 39
Change of habit in larva, 301, 431
Chapman, Dr. T. A., on _Chrysis_, 3;
on classification of pupae of Lepidoptera, 367;
on _Hepialus_, 398;
on _Metoecus paradoxus_, 268;
on pupa of Lepidoptera, 327 n.
_Charagia_, 396
_Chartergus chartarius_, nest of, 82, 83
_Cheilosia chrysocoma_, 439
_Cheimatobia brumata_, 414
_Cheliomyrmex_, _180_
Chelonariides, 242
_Chelonia_, 410
_Chelostoma_, _35_
_Chennium bituberculatum_, 224
_Chermes_, 583, 586, 587;
_C. abietis_, 586, 587, 589
Cheshire, on proboscis of bee, 15
Chigger, 525
Child, on sense-organ, 442
China-marks, 421
Chinch-bug, 548
_Chionea araneoides_, 474
Chiromyzidae, 479
Chironomidae, 468, _474_
_Chironomus_, 440, 468
Chlamydes, _279_
_Chlorion_, 110ü
Chloropidae, _504_
_Chlorops_, 504
_Choerocampa elpenor_, 380
Choerocampini, 381
Cholodkovsky on _Chermes_, 586
_Choragus sheppardi_, 290
Chorion, 322
Chrysalis, 326, 344
Chrysauginae, 423
Chrysididae, 1 f.
_Chrysiridia madagascariensis_, 419
_Chrysis bidentata_, 3;
_C. ignita_, 3;
_C. shanghaiensis_, 4
_Chrysochus pretiosus_, 279
_Chrysocoris grandis_, 303 n.
Chrysomelidae, _276_, 278 f.
Chrysomelides, _279_
Chrysopolomidae, 396
_Chrysops_, 482
_Cicada_, 123;
_C. plebeia_, 574;
_C. septendecim_, 569
Cicadellinae, 578
Cicadidae, 568 f.
_Cicindela hybrida_, 202
Cicindelidae, 201 f.
_Cicinnus_, _378_ n.
_Cilix glaucata_ = _spinula_, 401
_Cimex_, _560_;
_C. lectularius_, 559
Cimicidae, 559
Cioidae, 245
_Cis melliei_, 245
Cistelidae, 264
_Cistus salvifolius_, beetle-larvae in, 282
_Cithaerias_, 348
_Citheronia_, 375
Cixiides, _576_
_Cixius_, 575
Clambidae, _223_
Clasper, 314
Classification, of ants, 144;
of bees, 20;
of butterflies, 341;
of Coleoptera, 189;
of Diptera, 454 f.;
of Hemiptera, 543;
of Hymenoptera Aculeata, _10_;
of Lepidoptera, 339 f.;
of moths, 366 f.
Clavicornia, _189_, _213_, 265
_Claviger testaceus_, 224
Clavigerides, 224
Clavus, 539
Clear-wings, 386
Cleggs, 481
_Cleosiris_, 400
_Cleptes_, 2, 4
Cleridae, 253
Click-beetles, 256 {608}
Clicking butterfly, 354
_Clidicus_, 223
_Clisiocampa neustria_, 322
Clothes-moths, 430
Clouded-yellows, 357
Clypeus, 307
_Clythra_ in ants'-nests, 149
Clythrides, _279_
_Cnemidotus caesus_, 209
_Cnethocampa processionea_, 376
Coarctate larva, 271
Coccidae, 592 f.;
destroyer of, 290
_Coccidula_, _239_
Coccinellidae, 237
_Coccus cacti_, 598;
_C. mannifera_, 597
Cochineal Insect, 598
Cochliopodidae, 402 n.
_Cochlophora_, 394
Cockchafer, 198
Cockroach, parasite of, 269
Cock-tail, 225
Cocoon, 46, 55, 66, 109, 122, 328, 347, 373, 376, 384, 385, 391, 403,
404, 405, 407, 419, 424, 436, 460, 462, 494;
flax-seed, 460;
of ants, 134;
aquatic, 280, 377
_Cocytia durvillii_, 382
Cocytiidae, 382
Codling-moth, 428
_Coelioxys_, 31
_Coelonites_, _89_;
_C. abbreviatus_, cells of, 89
_Coenomyia ferruginea_, 480
Coenomyiidae, 479
_Coenonympha_, 348
_Colaenis_, _351_
_Coleophora_, 431
Coleoptera, 184 f.
_Colletes_, 22;
_C. daviesanus_, 30
_Colobopsis_, 138
Colon, 320
Colorado beetle, 278
Colour, corresponding with locale, 201;
and surroundings, 337;
of larva and habits, 336;
of Sphingidae larvae, 381;
physiology of larval, 413;
of caterpillars and sex, 325;
development of, in Hemiptera, 542;
of eyes, 440
_Coluocera formicaria_, 240
Colydiidae, 233, 234
_Colydium_, 233
Comb, 63, 64, 65, 78, 79
Combs and brushes, 134
Compound pupa, 452
_Composmyia_, 512
Comstock, on nervures, 317 n.
Conchylidae, _427_
Connexivum, 538
Conopidae, 497, _504_
_Conorhinus sanguisuga_, 559
_Copiopteryx_, 373
_Copium clavicorne_, 550
_Copius_, 547
Copper butterflies, 356
Coprides, 195 f.
Coprini, _195_ n.
_Copris hispanus_, 197
Copulatory pouch, 320, 321
Cordyluridae, _504_
Coreidae, 546
_Corethra_, 467
Corium, 539
_Corixa_, 567
Corixidae, 567
Corn-leaves, larva on, 281
_Coronidia_, 419
_Corotoca_, 227
_Corticaria_, 240
Corylophidae, 228
Corynetides, 253
_Coscinocera hercules_, 372
Cossidae, _369_, 395
Cossonides, 294
_Cossus_, 309;
_C. ligniperda_, 319
Costal nervure, 318
Cotton-stainer bug, 548
Cotton-worm, 416
Courtship, 494;
of _Hepialus_, 398 f.
Coxa, 307
_Crabro_, 129;
_C. cephalotes_, 129;
_C. stirpicola_, 130 n.
Crabronides, 128 f.
Crambidae, 425
Crane-flies, 471
_Cratoparis_, 290
Cremaster, 327, 328, 344, 426
Cremastochilini, 200
_Cremastochilus_, 200
_Cremastogaster_, 165, 213;
_C. tricolor_, 165
Crepitation, 213, 214
Criocerides, _279_, 280
_Crioceris asparagi_, 281;
_C. merdigera_, 281
_Crossocerus_, 130;
_C. wesmaeli_, 130
Cryptocephalides, _279_
_Cryptocephalus_, _282_
Cryptocerata, _544_, 562 f.
Cryptocerini, 132, 134, 158, 159, 169
_Cryptocerus_, 138;
_C. atratus_, 170
Cryptophagidae, 235, _237_
_Cryptophagus dentatus_, 235
Cryptostomes, _279_, 282
_Cteniza ariana_, destroyer of, 490
_Ctenophora_, 475
Ctenostylidae, 517
Ctenuchinae, _409_
Cuckoo-bees, 22
Cuckoo-spit, 577
Cucujidae, _232_, 234
Cucujos, 258
Cuculinae, _20_
_Culex pipiens_, 466
Culicidae, 466 f.
Cultelli, 443
Cuneus, 539, 540 {609}
Cupesidae, 234
Curculionidae, 290
Curtice, on _Hypoderma_, 516
_Curupira_, 465
Cut-worms, 415
Cyathoceridae, 243
_Cybister laterimarginalis_ or _roeseli_, 210;
_C. tripunctatus_, 211
_Cybocephalus_, 232
Cyclica, _279_, 282
Cyclorrhapha, 454;
_C. Aschiza_, 455, 494 f.;
_C. Schizophora_, 456, 503 f.
_Cylidrus_, 253
Cylindrotomina, 474
Cymatophoridae, _368_, 386
Cymbidae, 410
_Cynomyia mortuorum_, 510
_Cyphagogus segnipes_, 296
_Cyphanta_, _368_ n.
_Cyphonia clavata_, 576
Cyphonidae, 255
Cyrtidae, 489
Cyrtocorides, 545
_Cyrtocoris monstrosus_, 546

Dacnides, 237
_Dactylopius citri_, 595
Daddy-long-legs, 471
_Dakruma coccidivora_, 424
Dalla Torre, Catalogue of Hymenoptera, 21
Danaides, 344, _347_
Danaioid Heliconiidae, 346
_Danais archippus_, or _plexippus_, 345
Dances, 351, 464, 493, 554
Darwin, C., on _Pelobius_, 208
Darwin, F., on proboscis of Lepidoptera, 311 n.
Dascillidae, _243_, 255
_Dascillus cervinus_, 255
_Dasychira pudibunda_, 408;
_D. rossii_, 407
Dasygastres, _20_, 35 f.
_Dasypoda hirtipes_, 27
Dead-leaf butterfly, 353
Death-watches, 248, 254
December-moth, 406
Deer bot-fly, 517
Deer-fly, 518
Delphacides, _576_
_Deltocephalus inimicus_, 578
Deltoidae, 418, _423_
Denudatae, _20_, 29
_Deporaus_, 291
_Dermatobia noxialis_, 517
Dermestidae, 241
_Deroca_, 400
Derodontidae, 244, _253_
_Derodontus maculatus_, 245
De Saussure, on wasps' nests, 81
Devil's coach-horse, 225
Dewitz, on development, of sting, 8;
of thoracic appendages, 9
Dexiidae, 510
_Diactor bilineatus_, 547
_Dianeura_, 392
_Diateina holymenoides_, 547
Dichoptic, 440
_Dicthadia_, 178, 180
_Dictyocicada_, 543
_Dilophus febrilis_, 477;
_D. vulgaris_, 476
Dimera, _544_
Dimorphic, generations, 586;
males, 161, 172
Dimorphism, 139;
of wings, 549
_Dinapate wrightii_, 246
Dingar, 70
_Dinoponera grandis_, 132, 134, 171
_Dionychopus niveus_, 410
Diopsidae, 503, _504_, 505
_Diopsis apicalis_, 503
Dioptinae, 409
_Dioptoma adamsi_, 251
_Dioscorea batatas_, beetle-larvae in, 280
_Dioxys cincta_, 32, 43
Diphyllides, _237_
_Diplocotes_, _248_
_Diplonychus_, 566
_Diploplectron_, 119
Diploptera, _10_, 71 f.
_Diplosara lignivora_, 429
_Diplosis_, 459;
_D. resinicola_, 459
_Dipsocoris alienus_, 559
Diptera, 438 f.
Dipterous parasitic larva, 26
_Dirphia tarquinia_, 377
Discocellular nervures, 318
_Dismorphia_, 346, 357
Dissociation of embryo, 70 n.
_Dixa_, 471
Dixidae, 471
Dohrn, Anton, on Hemiptera, 538
_Dolichoderides_, _157_
Dolichopidae, 493
_Dolichopus undulatus_, 441
_Dolichurus haemorrhous_, 116
_Donacia_, 280
Donaciides, 279
Dorsal vessel, 320;
529—see also Internal Anatomy
_Dorycera_, 504
Doryceridae, _504_
Dorylides, 174 f.
Dorylini, _175_, _177_
_Dorylus_, 133, 177, 179;
_D. helvolus_, 178
_Doryphora decemlineata_, 278
Dragon, 383, 385
Drepanidae, _370_, 400
_Drepanosiphum platanoides_, 585
Drepanulidae, 400
Drilides, _248_
Driver ants, 178
Drones, 63, 67, 69 {610}
Drosophilidae, _504_
_Drurya_, 362
Dryomyzidae, _504_
_Dryophthorus_, _289_
Dubois, on luminescence, 259
Dudgeon, on _Badamia_, 365
Dufour, on host helping parasite, 26
Duke of Burgundy fritillary, 355
Duration, of ant-colonies, 154;
of wasp-colonies, 70 n., 80;
of life—see Longevity
Durrant, on moth-cases, 431
Dutch bulbs, larva in, 501
Dyar, classification of larvae of moths, 367
_Dycladia_, 389
_Dynastes_, 199
Dynastides, _195_, 199
_Dysdercus suturellus_, 548
Dytiscidae, 210 f.
_Dytiscus_, 211

_Earias_, 410
Eau de Javelle, 368 n.
_Echinophthirius_, 600
_Eciton_, 159, 175, f;
_E. hamatum_, 175, 177
Ecitonini, _174_, 175 f.
_Ecpantheria_, 409
_Ectatomma auratum_, 131
_Ectrephes kingi_, 248
Edible larvae, 287
Egg, 305, 435, 468;
as food, 504, 568;
of bot-fly, 514, 515;
of Capsidae, 561;
carried, 547, 551, 566;
of _Endochus_, 558;
of Reduviidae, 559;
of flea, 524;
laid by pupa, 469;
of Lepidoptera, 321, 322;
of _Nepa_, 564;
numerous, 397, few, 197;
standing out string of, 378;
swallowed, 508
Egg-tubes, 321
Eggers, 322, 405
_Elaphidion villosum_, 286
_Elaphomyia_, 505
Elateridae, 256
Elaterides, _260_
_Eleodes_, 263
_Elephantomyia_, 472
Elmides, 244
_Elymnias_, 348
Elymniidae, 348
Elytra, 184, 186, 539
Embolium, 539
Embryonic dissociation, 70 n.
_Emenadia flabellata_, 269
Emery on classification of ants, 144;
on polymorphism in ants, 143
Emesiides, 555
Emperor-moth, 374
Empidae, 492, _494_
Empodium, 446
_Empretia stimulans_, 403
_Encyrtus_, 34;
_Encyrtus fuscicollis_, embryology of, 70
Endomychidae, _237_, 239
Endotrichiinae, _423_
Endromidae, _369_, 406
Energopoda, _457_, _491_
_Enhydrus_, 216
Entomophila, _10_
Enzyme, 259
_Epeolus variegatus_, 30
_Ephestia kuhniella_, 306, 424
Ephydridae, _504_
_Ephyra pendularia_, 412
Epiblemidae, _427_
_Epicausis smithi_, 409
_Epichnopteryx_, _395_
Epicopeiidae, _368_, 418
Epicranium, 307
_Epicypta scatophora_, 463
_Epidapus scabiei_, 462
Epilachnides, 238
Epimeron, 307
_Epinotia funebrana_, 428;
_E. hypericana_, parasite of, 476
Epipaschiinae, _423_
Epipharyngeal sclerites, 14
Epipharynx, 14, 308, 443, 600
Epiplemidae, _368_, 420
_Epipyrops_, 404
Episternum, 307
_Epitritus_, 170
_Epuraea_, 232
_Erastria scitula_, 417
_Erebia_, _347_;
_E. aethiops_, 347
Erebides, 418
Eremochaeta, _457_
Eremochaetous, 446
_Eremocoris_, 548
Ergatandrous, 140 n.
Ergatogynous, 140 n., 142
Ergatoid, 140
_Ericerus pela_, 597
_Eriocephala_, 308;
_E. calthella_, 434
Eriocephalidae, 433
_Eriocera_, 472
_Eristalis_, 499
Ermine-moths, 409
Erotylidae, _235_, 236
Erucaeformia, 475
_Erycides_, _364_
Erycinidae, _341_, 354, _358_
Erycinides, _355_
_Ethon_, 262
Eucephalous larvae, 450
_Eucera_, _32_
_Eucharis myrmeciae_, 173
_Euchloe cardamines_, egg, 322;
larva, 358, 359;
pupa, 358;
_E. genutia_, 358
_Euchroma goliath_, 261
_Eucinetus_, 256
Eucleidae, 401
_Euclidia mi_, 415
Eucnemides, 260 {611}
_Eudaemonia_, 373
_Eudamus proteus_, 340
_Eueides_, 351
_Eugereon hockingi_, 542
_Euglossa_, 34;
_E. cordata_, 35
_Eugnoristus monachus_, 289
_Eulema_, 35
Eulen, 414
_Eulyes_, 558
_Eumaeus_, 355
_Eumenes arbustorum_, 73;
_E. coarctata_, 73, 74;
_E. conica_, 74;
_E. flavopicta_, 72;
_E. pomiformis_, 72;
_E. unguiculata_, 73
Eumenidae, 72 f.
Eumolpides, _279_
Eumyiid flies, _456_
_Euparagia_, 89
_Euphoria_, 200
_Euplocia_, 408
_Euploea_, 345
Eupoda, _279_, 280
_Eupsalis minuta_, 296
Eupterotidae, _368_, 376
_Eurygona_, larva, 355
_Euschemon rafflesiae_, 371
_Eusemia vitticoides_, 410
_Eusthenes pratti_, 533
_Euthyrhynchus floridanus_, 546
_Excoecaria biglandulosa_, 424
Excrement as covering, 281, 283, 463—see also Adapted excrement.
Excremental dwellings, 284, 379
External structure, of Aphidae, 588;
of Chrysididae, 2;
of Coleoptera, 185;
of Diptera, 439 f.;
of fleas, 523;
of Hemiptera, 534;
of _Hepialus_, 400;
of Hymenoptera Aculeata, 5;
of Lepidoptera, 307 f.;
of Thrips, 527
Exudation of fluid, 238
Eye-collar, 387
Eyes, four in number, 215, 251, 476