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MONTHLY JOURNAL OF AGRICTJLTURE. 



ber, along each side of the body. Some, how- 

 ever, have die breathing-holes placed in the 

 hinder extremity, and a fe-w young water-in- 

 sects breathe by means of gills. The heart is a 

 long tube, lying under the skin of the back, 

 having little holes on each side for the admis- 

 sion of the juices of the body, which are pre- 

 vented from escaping again by valves or clap- 

 pers, formed to close tlie holes within. More- 

 over, this tubular heart is divided into several 

 chambers, by transverse partitions, in each of 

 which there is a hole shut by a valve, which al- 

 lows the blood to flow only from the hinder to 

 the fore part of the heart, and prevents it from 

 passing in the contrary direction. The blood, 

 which is a colorless or yellowish fluid, does not 

 circulate in proper arteries and veins; but is 

 driven from the fore part of the heart into the 

 head, and thence escapes into the body, where 

 it is mingled with the nutritive juices that filter 

 through the sides of ilie intestines, and the min- 

 gled fluid penetrates the crevices among the 

 flesh and other internal parts, flowing along the 

 s;des of the air-pipes, whereby it receives from 

 the air that influence which renders it fitted to 

 nourish the frame, and maintain life. 



All in.sects are produced from eggs, and none 

 are spontaneously generated from putrid animal 

 or vegetable matter. A few iu-sccts, such as 

 some plant-lice, do not lay their eggs, hut retain 

 them within their bodies till the young are ready 

 to escape. Other insects invariably lay their 

 eggs where their young, as soon as they are 

 hatched, will find a plentiful supply of food im- 

 mediately within their reach. 



Most insects, in the course of their lives, are 

 subject to verj- great changes of form, attended 

 by equally remarkable changes in their habits 

 and propensities. These changes, transforma- 

 tions, or metamorphoses, as they are called, 

 might cause the same insect, at different ages, 

 to be mistaken for as many different animals. 

 For example, a caterpillar, after feeding upon 

 leaves till it is fully grown, retires into some 

 place of concealment, casts oflT its caterpillar 

 skin, and presents itself in an entirely different 

 form, one wherein it has neither the power of 

 moving about, nor of taking food ; in fact, in this 

 its second or chrysalis state, the insect seems to 

 be a lilele.«s, oblong, oval or conical body, with- 

 out a distinct head, or movable limbs; after 

 resting a while, an inward struggle begins, the 

 chrysalis skin bursts open, and from the rent is- 

 sue's a butterfly, or a moth, whose small, flabby 

 w^ings soon extend and harden, and become fit- 

 ted to bear away tlie insect in search of the 

 honeyed juice of flowers and other liquids that 

 suSice for its nourishment. 



The little fish-like animals that swim about in 

 vessels of stagnant water, and devour the living 

 atoms that swarm in the same situations, soon 

 come to maturity, cast their skins, and take an- 

 other form, wherein they remain rolled up like 

 a ball, and either float at the surface of the wa- 

 ter, tor the purpo.ae of breathing through the two 

 tunnel-shaped tubes on the top of their backs, 

 or, if disturbed, suddenly uncurl their bodies, 

 and whirl over and over from one side of the 

 vessel to the other. In the course of a few 

 days these little water- tumblers are ready for 

 another transformation ; the skin splits on the 

 back between the breathing-tubes, the head, 

 body, and limbs of a musketo suddenly burst 

 from the opening, the slender logs rest on the 

 empty skin till the latter fills with water and 

 sinks, when the insect abandons its native ele- 



ment, spreads its tiny wings, and flics away, 

 piping its war-note, and thirsting for the blood 

 which its nattiral weapons enable it to draw 

 from its unlucky victims. 



The full-fed maggot, that has rioted in filth till 

 its tender skin seems ready to burst with reple- 

 tion, when the appointed time arrives, leaves 

 the offensive matters it was ordained to assi.st in 

 removing, and gets into some convenient hole 

 or crevice : then its body contracts or shortens, 

 and becomes egg-shaped, while the skin hard- 

 ens, and turns brown and dr\-. so that, under 

 this form, the creature appears more like a seed 

 than a living animal ; after some time passed in 

 this inactive and equivocal form, during which 

 wonderful changes have taken place within the 

 seed-like shell, one end of the shell is forced off, 

 and from the in.side comes forth a buzzing fly, 

 that drops its former filthy habits with its cast- 

 off dress, and now with a more refined taste, 

 .seeks only to lap the .solid viands of our tables, 

 or sip the liquid contents of our cups. 



Caterpillars, grubs, and maggots undergo a 

 complete transformation in coming to maturity ; 

 but there are other insects, such as crickets, 

 grasshoppers, bugs, and plant-lice, which, though 

 differing a good deal in the young and adult 

 states, are not subject to so great a change, their 

 transformations being only partial. For 

 stance, the young grasshopper comes from the 

 e^^ a wintjless insect, and consequently unable 

 to move from place to place, in any other way 

 than by the use of its legs; as it grows larger it 

 is soon obliged to cast off its skin, and, after one 

 or two moultings, its body not only increases in 

 size, but becomes proportionally loncer than 

 before, while little stump-like -w ings begin to 

 make their appearance on the top of the back. 

 After this, the grasshoppercontinues to eat vora- 

 cioush', grows larger and larger, and hops about 

 without any aid from its short and motionless 

 wings, repeatedly casts off its outgrown ."^kin, 

 appearing each time with still longer win^ 

 and more perfectly formed limbs, till at length 

 it ceases to grow, and, shedding its skin for the 

 last time, it comes forth a perfectly formed and 

 matured grasshopper, with the power of spread- 

 ing its ample wings, and of using them in flight. 



Hence there are three ^jeriods in the life of 

 an insect, more or less distinctly marked by cor- 

 responding changes in the form, powers and 

 habits. In the first, or period of infancy, an in- 

 sect is technically called a Jo no, a word signi- 

 fying a mask, becau.se therein its future form 

 is more or less masked or concealed. This 

 name is not only applied to grubs, caterpillars, 

 and maggots, and to other insects that undergo 

 a complete transformation, but also to young 

 and wingless grasshoppers, and bugs, and in- 

 deed to all joung insects before the wings be- 

 gin to appear. In this first period, which is 

 generally much the longest, insects are always 

 wingles.s, pass most of their time in eating, grow 

 rapidly, and usually cast off' their skins repeat- 

 edly. " The second period, wherein those in- 

 sects that undergo a partial transformation, re- 

 tain their activity and their appetites for food, 

 continue to grow, and acquire the rudiments of 

 wings, while others at thi.s age, entirely lose 

 their larva form, take no food, and remain at 

 rest in a death-like sleep— is called the pvpa 

 state, from a slight resemblance that some of the 

 latter present to an infant trasscd in bandages, 

 as was the fashion among the Romans. The 

 pupae from caterpillars, however, arc more com- 

 monly called chrjsalids, because some of them, 



