them. 17. Do you often become weary ? 18. I become weary when chlorine is passed. The chlorine seizes the magnesium, and I have nothing to do. 19. How do you amuse yourself when you are

sets free the bromine, which gives a reddish-yellow colour to the in the country ? 20. We walk in the morning, and work the re

liquid. The bittern is now shaken with ether, which dissolves mainder of the day.

the bromine and floats on tho surface; it is decanted into a glass EXERCISE 70 (Vol. I., page 334).

vessel; a little caustic potash being added, potassium bromide is 1. Ne vous trompez-vous pas ? 2. Je ne me trompe pas. 3. Le made. This process is frequently repeated, the same ether being banquier ne se trompe-t-il pas ? 4. Il ne se trompe pas, mais son com- used. The potassium bromide which is thus prepared is mixed mis se trompe certainement. 5. Ne vous trompe-t-il pas ? 6. Il ne

with black oxide of manganese and sulphuric acid in a retort; me trompe pas, il ne trompe personne. 7. N'avez-vous pas tort de

The reaction is thus tromper votre père ? 8. Je n'ai pas l'intention de le tromper. heat being applied, bromine distils over. 9. Le marchand ne se trompe-t-il pas ? 10. Il se trompe dans le expressedmémoire qu'il écrit. 11. Aimez-vous la ville ou la campagne ? 12. Je

2BrK + 2H SO, + Mno, = 2Br + K,80 + MnSo, + 21,0. préfère la ville, je m'ennuie bientôt à la campagne. 13. Cet enfant De rous ennuie-t-il pas par ses questions ? 14. Cette longuo his. It will be noticed that this process is identical with that of toire ne rous ennuie-t-elle pas ? 15. Elle ne m'ennuie pns, elle liberating chlorine from common salt. m'amuse. 16. Vous amusez-vous quand vous êtes à la campagne ? Properties. --Bromine is a liquid of a deep red colour, having 17. Je m'y amuse, j'apprends le français et l'italien. 18. Ne vous a density of 2.966. It boils at 47° Cent., and evaporates at all ennuyez-vous pas chez votre oncle ? 19. Je ne m'y ennuie jamais. temperatures. Its vapour is a dense red. If swallowed, it 20. M. votre frère se trompe-t-il souvent ? 21. Tout le monde se operates as a powerful irritating poison. It bleaches more feebly trompe quelquefois. 22. Sa conversation vous ennuie-t-elle ?

23. Au than chlorine, but will not support the combustion of a taper. contraire, elle nous amuse. 24. Reçoit-on des nouvelles de M. votre

It combines with many metals forming “bromides." frère ? 35. On n'entend pas parler de lui. 26. Malle. votre saur se porte-t-elle bien ? 27. Non, Monsieur, elle est malade.

Hydrobromic Acid (symbol, HBr ; combining weight, 81 ;

density, 40:5).—This compound cannot be made like hydroEXERCISE 71 (Vol. I., page 342).

chloric acid from the combination of hydrogen and bromine in 1. Can you do without ink? 2. We can do without it, we bave nothing the sun-light, but the elements will combine if passed through to write. 3. Do you use your pen ? 4. I am not using it, do you a red-hot porcelain tube. It may also be obtained by decomWidt it? 5. Will you not draw near the fire ? 6. I am much obliged posing the bromide of phosphorus by water. Thusto you, I am not cold. 7. Why do those young ladies go from the window? 8. They leave it because it is too cold there. 9. Do not

PBr, + 44,0 = H,PO, + 5BrH. those children apply to you? 10. They apply to me and to my The experiment is performed by a tube bent as in Fig. 44. In brother. 11. At what hour do you awake in the morning ? 12. I awake generally at a quarter before six. 13. Do you rise as soon as

the bend P pieces of phosphorus are placed, separated from you awake? 14. I rise as soon as I awake.

In the bend B is 15. What books do each other by fragments of moistened glass. you use?

16. I use mine and yours. 17. Do you not use your placed a little bromine, and the tube closed by a cork. On brother's ? 18. I use them also. 19. Are the pens which you use applying a gentle heat at B, the bromine vapours pass into P, good ? 20. Why does your friend draw back from the fire ? 21. He where the bromide of phosphorus is formed and is decomposed draws back because he is too warm. 22. Why does your servant draw by the water on the glass. The hydrobromic acid thus produced Dear it ?

23, He drawg near to warm himself. 24. Are you becoming passes out from T. It is a colourless gas, and can be liquefied weary of being here? 25. I am not weary of it.

under strong pressure. Its action on metallic oxides is analogous EXERCISE 72 (Vol. I., pago 342).

to that of hydrochloric acid, forming a bromide of the metal and 1. Voulez-vous me prêter votre canif? 2. Je ne puis m'en passer, water. j'en ai besoin pour tailler ma plume. 3. Voulez-vous vous servir de

COMPOUNDS OF BROMINE WITH OXYGEN. mon livre ? 4. J'ai besoin de m'en servir, voulez-vous me le prêter ? 5. De quel couteau M. votre frère se sert-il ? 6. Il se sert du couteau

Hypobromous Acid (Symbol, HBrO).—An aqueous solution of de mon père et de la fourchette de mon frère. 7. Ne voulez-vous pas

this acid can be obtained by agitating bromine water with the vous approcher du feu ? 8. Nous vous sommes bien obligés, nous

oxide of mercury. In distilling the solution, care must be taken avons chaud. 9. Cette demoiselle a-t-elle assez chaud ? 10. Elle a not to raise the temperature above 30° Cent., lest the hypobromous très-froid. 11. Dites-lui de s'approcher du feu ? 12. Pourquoi vous acid should be decomposed into bromic acid and free bromine. Coignez-vous du feu ? 13. Nous avons trop chaud. 14. M. votre frère The aqueous solution of the acid is light yellow, has a sweetish s'éloigne-t-il de la fenêtre ? 15. Il s'éloigne de la fenêtre parcequ'il a taste, and is a powerful bleaching agent. froid. 16. À qui ce monsieur s'adresse-t-il ? 17. Il s'adresse à moi

Bromic Acid (symbol, HBrO2) is formed when chlorine is et å mon frère. 18. Pourquoi ne s'adresse-t-il pas à mci? 19. Parce

passed into bromine water. Thusqu'il , honte de vous parler. 20. Vous éveillez-vous de bonne heure, tous les matins ? 21. Je m'éveille de bonne heure, quand je

Br + 3H,0 + 5C1 = 5HCl + HBrO,. mne couche de bonne heure, 22. Pourquoi vous endormez-vous ? With bases this acid forms “bromates," which salts are decom23. Je m'endors parceque je suis fatigué. 24. Avez-vous peur de vous approcher de votre père ? 25. Je n'ai pas peur de m'approcher de posed by heat in the same way as chlorates. lui. 28. Pouvez-vons vous passer de nous ? 27. Nous ne pouvons

Bromine forms with hydrogen an oily detonating liquid, whích nous passer de vous, mais nous pouvons nous passer de votre frère. resembles the chloride of nitrogen. 8. Avez-vous besoin du cheval de mon frère ? 29. Non, Monsieur,

IODINE. nous pouvons nous en passer.

30. Avez-vous l'intention de vous passer d'argent ? 31. Vous savez très-bien que nous ne pouvons nous

SYMBOL, I-COMBINING Weight, 127— DENSITY, 187. en passer.

32. M. votre frère s'ennuie-t-il ici ? 33. Il ne s'ennuie pas Iodine is found in the sea in really less qnantities than bromine, ici. 34. Approchez-vous du feu, mon enfant.

but it is obtained with more oase, for the sea-weeds, etc., store it in their tissues. When these are burnt, the ash, which is called

kelp, is broken into small fragments, digested with boiling water, LESSONS IN CHEMISTRY.-XIV. and the solution thus formed is evaporated down until a film BROMINE.

forms on its surface, when it is set aside to crystallise. Sodium

sulphates and carbonates and potassium chloride separate. STYBOL, Br ATOMIC WEIGHT, 80


The mother liquor is treated with one-eighth of its bulk of Is many of its properties this element resembles chlorine, but sulphuric acid, and after it has stood to allow the precipitates to its affinities are not so strong, since it can be displaced from its fall, and some of the sulphates to crystallise out, the clear combinations by that gas. It owes its name to the severe liquid is mixed with manganese dioxide, and introduced into a manner in which it affects the respiratory organs. Bpwuos is leaden retort. Upon the application of heat, iodine passes into the Greek for “stench." It never occurs free in nature, but the receivers and condenses. The reaction isis found combined with magnesium in sca-water, especially in

2Nal + 2H,SO, + Mno, that of the Dead Sea. The peculiar smell of sea-weed is due

Na,so, +Mnso, + 2H,0 + 21. to its presence. Berthier discovered it in a silver ore from Properties.-Iodine is a solid, which crystallises in plates, Mexico, but it is invariably obtained from the “ mother liquor" having a brilliant metallie lustre; when a little is heated at the

bottom of a test-tube, beautiful violet vapours are given off, Preparation.—A quantity of sea-water is reduced by evapo- which condense in the upper part of the tube into the solid nation; the crystallisable salts, sodium chloride, etc., "crystallise iodine. This colour gives the element its name, wôns being the opt;" into the “bittern” which thus remains a stream of Greek for violet.

of the sea.

Iodine gives off vapour at all temperatures, and must there- of three atoms of caustic soda, and one atom of sodium fore be kept in a bottle with a glass stopper, as the vapours iodate. attack cork. The skin and organic bodies are stained by it Nitric iodide, which is generally supposed to be the ter-iodide of yellow. This stain, however, passes away so soon as the iodine nitrogen (NI.), is an interesting compound, from the readiness evaporates. It is slightly soluble in water, this liquid being with which it explodes. Place a little iodine in a capsule, and capable of holding row of its weight in solution. It is freely pour upon it sufficient ammonia to cover it well. Allow this to dissolved in alcohol and ether, and a minute piece of iodine im- digest for half an hour; then pour off the supernatant liquid, parts a rich colour to bisulphide of carbon; but the chief liquid em- and place the brown substance upon pieces of blotting paperployed for its solution is the solu.

littlo on each paper ; leave them tion of a soluble iodide, such as

to dry, if by a fire, at some distance potassium iodide.

from it. When dry, a shake of The most delicate test for iodine

the paper is sufficient to determine is the intense blue colour it imparts

the decomposition with explosion. to starch. However, to effect this,

Iodine is noted in the medical the iodine must be in an uncom.

world for its great powers of bined state. Chlorine water or

Fig. 4.

absorption. Glandular swellings nitric acid will always liberate

may be removed by it which have iodine from its combinations, and therefore, if the presence of an resisted every other means. It is used for this purpose in a soluiodide be suspected, add one or other of these agents to the tion, which is made as above described. Its action is greatly ac. solution, and then the starch paste. One part of iodine, dissolved celerated if a few grains of potassium iodide be taken internally in a million parts of water, will be made apparent by this test. each day. Hydriodic Acid (symbol, HI; combining weight, 128 ; density,

FLUORINE. 64). — This acid is best prepared in a manner similar to that by

SYMBOL, F-ATOMIC WEIGHT, 19. which hydrobromic acid was procured—namely

, by acting on ful. Its affinities are so powerful, and its action on the human

Hitherto no attempt to isolate this element has been success. phosphoric iodide with water, thus

frame so violent, that little is known of it. Its only compound PI, + 3H,0 = H,PO, + 3HI.

which occurs in any abundance, is Derbyshire spar, calcium However, it may be made directly by heating iodine in an atmo. Auoride (CaF2). Many minerals contain this salt in small sphere of hydrogen; or a solution of this acid may be easily quantities. It is detected in teeth, and even in the blood of prepared by suspending iodine in water, and transmitting a

animals. Fluorine is not known to combine with oxygen, nitrogen, current of sulphuretted hydrogen gas until the brown colour sulphur, or the other halogens. disappears. Sulphur is deposited, and hydriodic acid formed,

Hydrofluoric Acid (symbol, HF; combining weight, 20; den. which goes into solution in the water. If this solution bé sity, 10).—To prepare this acid, Derbyshire or fuor spar is exposed to the air in sunlight, it gradually absorbs oxygen, reduced to a powder, introduced into a leaden or platinum retort the hydrogen of the acid forming with it water, and the libe (Fig. 45), and then mixed with sulphuric acid. Upon the rated iodine renders the liquid brown. Iodides are formed by re- application of heat, this reaction ensues — placing the hydrogen of the above acid by the metal, according

H, 50, + CaF, = Caso, + 2HF. to its atomicity. When iodides are heated, the iodine goes off, The bent part of the tube in Fig. 45 is immersed in a freezing and an oxide of the metal is formed. Of course, in the case of mixture, and here the hydrofluoric acid condenses into a colourthe noble metals (Au, Ag, Pt, and Hg), the metal remains. The less liquid. elements, chlorine and bromine, when acting on iodides, have the It is an energetic acid, and has the power of converting power to remove the iodine, and insert themselves in its place. I metallic oxides into water and metallic fluorides. Of all chemical Oxides of Iodine.—This element

substances, its effect on the skin has a greater affinity for oxy.

is the most painful. It will progen than either of the preceding

duce a sore which exhibits but halogens; but of its oxides, the

small inclination to heal. Its most only two which have been studied

characteristic property is its power are iodic acid and periodic acid.

to etch on glass. It effects this, lodic acid, or hydric-iodate (sym.

because with silica-one of the bol, HIO3), corresponds closely to HT

constituents of glass-it forms a chloric acid. It is prepared by

gaseous product (Si F.), hydrofuothe action of strong nitric acid on

silicic acid : thusiodine. When the iodine has nearly disappeared, the liquid upon cool.

SiO, + 4HF = 24,0 + SiF, ing gives crystals of iodic acid.

To exhibit its effects, a glass When iodine is dissolved in

plate is covered with bees'-.2x, caustio potash or soda, the re

upon which fluorine has no action, sult is a mixture of iodide and

and any design traced with a sharp iodate of potassium or sodium.

point in the wax. This is exposed The iodate being much the most

to the vapour of hydrofluoric acid, difficult to dissolve, may easily

and the parts of the glass exposed be separated from the iodide.

Fig. 45.

are etched ; the glass is “frosted” Or if, in the course of the pro

by the vapour; but if the solution cess, chlorine gas be passed, then no iodide is formed ; thus, | of the acid, which is sold in gutta-percha bottles, be poured on I + 6KHO + 5C1 = KIO, + 5KCl + 3H,0.

glass, the glass is eaten away. Any photographic artist will

at once appreciate this fact to enable him to remove the frostWhen iodates are heated, they behave like chlorates, giving off ing from the back of the glass stereoscopic slides, and thus it oxygen.

will be possible to take “prints” from them. Iodic acid is at once decomposed by sulphurous acid. This The halogens form the best defined of natural groups of eleprovides a test for the presence of sulphur in any combustion. ments. Their atomic weights are almost in arithmetical proSoak a piece of paper in a mixture of potassium iodate and gression. starch-paste, then expose it to the fumes ; if any sulphurous acid be present, the paper becomes blue. Morphia possesses a

35:5. like power, and hence by this test the presence of this powerful poison may be detected.


127. Periodic Acid, or Hydric-periodate (HIO.).—This acid can Chlorine is a gas, bromine a liquid, and iodine a solid. only be obtained in combination. Sodium per-iodate (NaI0) over, bromine, in its affinities, is a 'mean between chlorine and may be prepared by passing chlorine through a solution iodine, and all form directly, with the metals, salts.

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COMPARATIVE ANATOMY.—XI. of insects, to have expended her most exquisite workmanship

in the architecture their superficies, or the boundary between INSECTA-CLASSIFICATION.

themselves and the outer world. The character, the capabilities, ENTOMOLOGY, or the study of insects, has always been a and the efficiency of insects depend mainly on the framework favourite branch of natural history. The great beauty, both of of their external casing. This external casing is the resisting form and colouring, to be found in many of the species of this and supporting structure upon which all the soft parts are class has always commended it to the attention of all who have built. From this peculiarity of structure it follows that when any bent towards such studies. Probably the hues of the an insect is dried—when the muscles have withered and its gorgeously-tinted butterfly, or the elegance and graceful ac- nervous, nutritive, and reproductive organs have shrivelled tivity of the dragon-fly, have been the first incitement to many or decayed-since they are all internal, not only is its beauty youth to the study of living creatures. Besides these, many left intact, but all the essential features by which its habits thousands who have no claim to be called naturalists have and relationships may be determined are undestroyed. Morefound great pleasure in collecting and preserving insects. “A over, it is found that when any class has any great pecuthing of beauty is a joy for ever,” and whether the external | liarity, any part specially well developed, the modifications of

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stamp of excellence called beauty induces men to examine and that part furnish the best means of classifying the members appreciate the other excellences of Nature or not, it is good that of that class into minor divisions. Thus, the gills of fish, the the great God should receive the praise of a thousand joyous breast-bone of birds, and the intra-uterine connection of mother hearts for this alone. The collection and study of insects is and offspring in brutes, all of which are peculiar or peculiarly pursued with greater ease than that of any other class. Found developed structures, are made use of severally to divide fish, everywhere in almost infinite variety, they offer an unlimited birds, and brutes into minor sub-divisions. Hence it follows field in which every lover of Nature can occupy himself. Their that though in our insect cabinets we have only the dry and size, ranging as it does between a very few inches in length lifeless husks of insects, yet we have in them a means of comdown to an almost limitless minuteness, enables them to be paring and classifying insects which probably would not be stored, notwithstanding their great multitude, in a space which much increased if the whole of the organs were preserved. is at the command of every one. All these facilities for the These advantages have no doubt largely tended to make the collection and study of insects would, however, be nugatory study of entomology popular. A class which can be studied if it were not for the peculiarities of their structure. As we with any degree of completeness without recourse to the diffi. have seen in our last lesson, the great peculiarity and excellence cult process of dissection, is sure to receive attention. A simple of insects is the perfection of the organs of relation, as they lens, or at most a microscope of low power, directed upon the are called. By organs of relation is meant the organs through exterior of a set specimen, is quite sufficient to determine not which the animal acts apon, or is brought into contact with, the only its place in all existing classifications, but even to furnish opter world, such as organs of sense, locomotion, and prehen all the information on which the reasons for the adoption of zion ; of attack and defence. Hence Nature seems, in the case the several systems of classification are based. Nevertheless,



though all that has been stated is true, though the museums 5. Coleoptera (sheath-winged).-Insects with perfect metaof Europe contain vast collections gathered from all parts of morphosis, biting jaws, free, strongly-developed prothorax, and the earth, though the class itself is so rich in species that is hard, horny fore-wings (Flytra). it, if anywhere, we might hope to find a complete series which 6. Neuroptera (net-winged).-Insects with perfect metamor. would throw light on the general principles of classification- phosis, biting jaws, free prothorax, and membranous fore and yet the arrangement of insects into minor groups is by no hind wings. means placed on a satisfactory footing. The external parts 7. Orthoptera (straight-winged). -Insects without or with of insects have been examined with a minuteness and described imperfect metamorphosis, biting jaws, and the first segment of with a care which strikes the uninitiated with wonder. Not the thorax united to the second segment. only the shape of all the plates composing the rings of the One thing should be noted in this ordinal arrangement which body, and the number and form of the joints of the legs and otherwise might perplex the student. The Dragon-fly family, antennæ, have been made to yield characters for classification, with its nearly allied families of the Ephemeridæ (May-flies) but even the number and shape of the joints of the appendages and the Perlidæ, are transferred from the Neuroptera to the of the mouth-organs, and the direction and number of the Orthoptera on account of their having a free prothorax. Now nervures of the wings, together with the shape of the cells the dragon-fly was once considered to be the very type of a which they circumscribe, have been impressed into the service neuropterous insect, and it seems probable that Linnæus of 'taxonomy. Yet naturalists are far from agrceing in the intended that it should be the type of the order he constituted; arrangement of insects into their larger groups. Some classi. nevertheless, it is certain that the dragon-flies and the may-flies fiers place all insccts under seven groups or orders, and some show a nearer relationship to the Orthoptera than the rest of are not contented with less than double that number. Con the so-called Neuroptera. cerning the more conspicuous and independent insects there The Hemiptera are so named from the fact that many of seems to be a considerable agreement as to classification, and them have their fore-wings distinctly divided into two parts; these are comprised under seven orders. The additional orders the anterior and outer half being horny, like the wing-cases of those who make more orders than seven are made of minute of a beetle, while the inner and hind half is membranous, like and generally parasitic insects. These, owing to the peculiarity the wing of a bee. of their method of life, constitute what may be called aberrant As this peculiarity only belongs to one large division of the groups--that is, groups which depart considerably from the order, some naturalists have given to it the name Rhynchota, or ordinary typical forms of insects. This idea of aberrant forms beaked insects, on account of the long rostrum or sucking will become clearer when we come to describe the several orders. snout which is found in every member of the order. These aberrant groups of insects have been constituted into new The order is divided into two tribes, the Homoptera and the orders, or included under the older and better established orders Heteroptera. In the Homoptera (like-winged) the wings are of the more conspicuous insects, according as each classifier of the same consistency throughout. One of the largest and is more prone to dwell on the differences or the resemblances most celebrated of these insects is shown in the illustraof animal forms.

tion. The insect represented is the female. The male is Without going into the merits of the several systems, we larger, and is furnished underneath with two large plates shall adhere to that classification by which all insects are covering in a musical apparatus, which it plies most vigorously arranged into seven orders, because this system will probably both during the day and night. The writer took this insect in give to the reader a clearer idea of the different groups of Italy, where it abounds, and has been known since classical insects than the ampler system. We have therefore to dis- times. The ancients called the cicada happy, because it had a tribute the aberrant groups among these seven orders, but in dumb wife. The cochineal insect, the aphides—whose periodical so doing we shall call attention to them, so that the reader presence in vast multitudes on plants is commonly called a may not be perplexed when he refers to other systems of blight--the Chinese lantern-fly, and the froghopper, all belong classification.

to this sub-order. Lice and bird-lice (Pediculina and Mallo The class Insecta is well defined by the following characters. phaga) may also be considered to be aberrant families of this subThey are animals with well-developed jointed limbs, one pair order, though some have made separate orders for each of them. of antennæ or head-feelers, compound eyes, feelerless upper The Heteroptera (unlike-winged) have wings such as have jaws (mandibles), a distinct head, a trisegmented thorax, to been described as giving their name to the Hemiptera. The which is attached three pairs of legs, and (normally) two pairs insect marked 2 in the illustration may be taken as a type of wings, limbless abdomen, and respiration by tracheæ.

of this sub-order. The water-scorpion, the water-boatman, and The terms used in this classification will be understood by the hydrometra cach represent families of this sub-order. The those who have read the last lesson. The whole definition last-named is represented in the engraving. It may be seen is necessary, in order to cut off the insects from all the neigh- skating over the surface of every piece of water in summer and bouring classes. Thus they possess jointed limbs in common autumn. with centipedes, spiders, and crustaceans, but they are by their The Diptera may be divided into the flies proper and two character cut off from the worms. Centipedes (Myriapoda) aberrant families. The lowest of these families is well known have one pair of antennæ, as insects have, but this peculiarity to us, being represented by the almost ubiquitous flea.

The severs these classes from the spiders, which have no antennæ, mouth-organs of this insect are very different from the genuino and also from the crustaceans, which have two pairs. On the flies, and in the place of wings they have only four scales, which other hand, the absence of limbs on the last division of the body, appear to be quite useless. Nevertheless, they appear from while it is likewise characteristic of the spiders, completely their metamorphosis, and for other reasons, to be more nearly separates them from the myriapods and crustaceans. The allied to the Diptera than to any other order. The Pupipera possession of two pairs of wings is pecnliar to insects, but still is the name given to other insects which are also parasitic and this is not a good distinctive character, because wings are not wingless. These pass the whole of their larva state in the body found in all insects.

of the mother. Insects as thus defined may be divided into the following The genuine flies may be divided into two great divisions, orders, to each of which we affix the ordinal definition:

one of which, the Brachycera (short-horned), have short antenne 1. Hemiptera (half-winged).--Insects with imperfect meta- composed of three joints, while the palpi are of one or two joints; morphosis, free prothorax, and snctorial months.

the other sub-order, named Nemocera (thread-horned), have their 2. Diptera (two-winged).-Insects with perfect metamorphosis, whip-like antennæ (sometimes beaded) in many joints, while the suctorial months, membranous naked fore-wings, and aborted maxillary feelers are four or five-jointed. The antenne also hind-wings.

often have fine secondary hairs springing from each joint, which 3. Lepidoptera (scale-winged).-Insects with perfect meta- gives them the appearance of a plume. This, in the common morphosis, suctorial mouthed organs, and membranous fore gnat, is a very pretty object. The common daddy-longlegs and hind wings, covered with close-set coloured scales.

(Tipula) is a good example of this order. Both of the flies in 4. Hymenoptera (membrane-winged).-Insects with perfect the illustration belong to the Brachycera. The hornet-fly is metamorphosis, biting jaws, small ring-shaped prothorax, firmly one of the largest of our British Diptera, and while in flight is fastened by its upper part to the succeeding segment, and mem- very like the insect from which it derives its specific name. branous fore and hind wings, of which the latter are the smaller. The Lepidoptera have been variously divided into groups. The sub-order, Macrolepidoptera, includes the day-flying butter- Physopoda and Thysanura. The earwigs (Dermoptera) are flies, with knobbed antennæ, the hawk-moths (Sphingidæ), the distinguished by their short, leathery, unveined elytra or forethick-bodied moths (Bombycidæ), the nocturna, and the loopers wings, which cover the membranous hind-wings. These latter (Geometridæ); while the other sub-order, Microlepidoptera, are folded when at rest, first in a longitudinal direction, and comprises the pearl-moths (Pyralidæ), the bell-moths (Tortri. then doubled up transversely, so as to occupy but little space. cida), the cloth-moths (Tineina), and the plume-moths (Ptero- When extended, these membranous wings are in shape like the phoridæ). The moth in the engraving belongs to the Nocturna, human ear, hence the name ear-wing, and its corruption earand is called Euclidia on account of the pattern of geometrical wig. The pincers at the end of the body, the uses of which figures formed by the coloured scales of the wings.

are so little known, furnish another character which is conspiThe Hymenoptera are divided into the Aculeate, or stinging ; cuous to all. Two more aberrant sub-orders, the Corrodentia the Entomophagous, or insect-eating; and the Phytophagous, and Physopoda (bladder-footed), are of littlo importance. or plant-eating, sub-orders. Some species of the latter sub- Another, called the Thysanura, is remarkablo for having long orders can prick, but the Aculeata are those which have a per bristles at the end of the body, which in the Podura are bent forated sting leading from a poison-bag. The males of these under the body, and serve as springs to jerk the insect into the have thirtzen joints, and the females twelve joints, to their air when it wishes to leap, much after the manner of the toy antennæ. The abdomen is connected with the thorax by a very leaping-frog. These creatures have their bodies covered with thin stalk. The females, or workers, usually feed the larvæ scales, which are so small yet so beautifully symmetrical in of grubs, which are walled up in cells. The bee, the wasp, and their markings as to make excellent test objects for the high the ant each represent different families of this order.

powers of a microscope. In the entomophagous Hymenoptera, the females are fur- The tribe to which the white ants belong is called Orthoptera nished with an ovipositor, placed between two side-plates, socialia, because they live in communities. Although they which are usually stretched freely out from the end of the belong to quito a different order from the true ants, yet the abdomen, and are often of great length. This complex instru- popular name is justified by the fact that their habits are ment is made use of to insert the eggs deep into the bodies closely similar to them. It is a singular coincidence that in of the larvæ of other insects, in the abdominal cavity of both the cases of the true and the white ants there are not which the footless larvæ live parasitically, and there change only males and females in the community, but also neutral into pupæ. Hence the enthusiastic lepidopterist who breeds wingless forms, which, though themselves sterilo, are highly his moths from caterpillars is often woefully disappointed instrumental in presiding over the reproduction and rearing of by having a brood of ichneumon-flies emerge from the chrysalis, the young from the other fertile forms, and also in the defence Fhose once living tenant they have entirely consumed. No. 8 of the nest and community. In the case of the Termites, the in the illustration represents an entomophagous insect. In the neuters are called soldiers, because of their immense jawa, phytophagous Hymenoptera, the abdomen is joined to the thorax wherewith they attack all intruders. The larvæ and pupe are by its whole width, and not by a stalk. These insects are active, and do the work of the community. The female has called sav-flies, because they are furnished with a double saw wings which have only a temporary use. When pregnant, she at the end of the body, with which they saw into wood, and is placed in a royal apartment, and fed while she increases to there deposit their young, which, when hatched, are herbivorous. an enormous size, preparatory to the production of some

The beetles (Coleoptera) form a well-definod order, with | 80,000 eggs. scarcely any other approach to other orders among any of their The Praying Mantis is a good example of another family. namerous families; and none of these families can be called The cognomen is applied on account of the bent fore-legs of aberrant—that is, they cannot be said to stray far away from the animal, which are supposed to represent the attitude of the true beetle type. By some, the Brachelytra—which have prayer. The mantis, however, ases them to inflict painful short wing-cases (as their name implies), under which their wounds by the aid of the sharp-pointed tibiæ. This insect is Al-xible wings are closely doubled up, thus leaving the rings an excellent example of the Gressorial Orthoptera. The salta of the hind part of the body exposed to view—are related to torial Orthoptera are well known as grasshoppers and crickets. the Forticulidæ, an orthopterous order. Certainly there is much external likeness between the devil's coach-horse and an earwig, which two insects represent the two families named, LESSONS IN ENGLISH.--XXVIII. bat this is rather a spurious resemblance than a true affinity.

THE LATIN ELEMENT, The main divisions of the beetles have been founded on the number of the joints of the foot below the tibia. Thus the In our last lesson (Vol. II., page 409) we finished our inquiry Pentamera have five joints to all their feet; the Heteromera into the influence that the ancient language of the Greeks has bare foar joints to the feet of the third pair of legs, and five exerted on our tongue, and we now pass on to the Latin element to the others. The Cryptopentamera have apparently four in the English language. joints to all their feet. This appearance is occasioned by the That element can by the ordinary student be appreciated anâ great reduction in size, or, as it might be called, the abortion acquired but imperfectly. I will, however, do what I can to aid of cne of the joints of each foot. The Trimera, similarly, have him. Had I had the direction of his studies from the first, I apparently three-jointed feet. Both the beetles in the engraving would have done my best to make him at the beginning master blong to the Pentamerous division. The Cicindela is a car- of the Latin language. As it is, I must content myself with n. rozous beetle, and the Geotrupas is an herbivorous lamellicorn offering to his diligent attention the chief Latin roots which mil., the last joints of the antenne are produced into flat, enter into the body of our tongue. Possessed of these, together appressed plates.

with their signification, he will in general bo at no loss, even The Neuroptera, narrowed by the transference of the dragon without the aid of a dictionary, for the meaning of a word of fies and the may-flies to the Orthoptera, is divided into the Latin parentago. Seldom, however, do the words in English Planipennin-in which the hind-wings are like the fore ones, which may be traced back to the Latin, come into our tongue and not folded--and the Trichoptera, in which the wings are directly from the Roman soil. They have generally passed hairy or scaly, and the hind pairs folded. To these divisions, through intermediate countries. also, unst be added the aberrant sub-order, called Strepsiptera From the Latin are formed several modern lanruages, namely, *Tew-winged). The males of these havo curious twisted and the French, the Italian, the Portuguese, and the Spanish. These aborted organs to represent the fore-wings and widely expanded are called the Romance languages, because they are essentially hind-wings; while the females are wingless, and inhabit the Roman in their origin. Some say they received tho namo because bodies of bees, between the segments of whose abdominal rings in them the first romances were written; moro probably is it they thrust forth their heads.

that the fictions so called were denominated from the languages The Orthoptera, as defined above, comprise not only the in which they appeared. getnine Orthoptera represented by the cockroaches, walking. It is not immediately from the pure Latin of the Latin lares, grasshoppers, and crickets - whose main characteristic classics, such as Livy, Cicero, Virgil, Horice, and Tacitus, that is the folding of their broad hind-wings longitudinally, after the Romance languages are derived, but rather from these so the manner of a lady's fan-but also the white ants, the ear. far as they were found in the vernacular tongue, the spoken wizs, and dragon-flies, etc., and also two aberrant groups, called language of the population in the great centres of intercourse

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