212 



NEW ENGLAND FARMER, 



•JANUARY 16, 1S33. 



A discourse; 



Delivered before the Massaclmsells HnrlicnUural Sorlel.v, on 

 the Celebration of its fourlli Anniversary, Oclol)er 3, lS3i!. 

 Uy Thaddeus William Hakkis, M. D. 

 [Continued from page 204.] 

 The introduction of foreign insects, in a country 

 before uninhabited by tbein, is a circumstance of 

 more importance than at first would be anticipated. 

 It may occur in various ways. Man, in his wander- 

 ings and migrations, has been instrumental in the 

 dispersion and colonization of a multitude of in- 

 sects. They adhere to his garments and bedding, 

 riot ill his stock of provisious, and link among his 

 imported seeds, fruits, plants, and drugs. The 

 bed-bug, the flea, the cock-roach, the bacon-grub,* 

 end tlie meal-worm, f have been universal travel- 

 ers, and are now citizens of the world. Com- 

 merce brought the first of these insects to England 

 from the continent at an early period.} "The 

 Scotch," it has been said, " bewail its introduction 

 among thein as one of the evils of the union, and 

 for that reason distinguish it by the name of the 

 I'-nglish bug." Kalm§ observes, that it was un- 

 known to the northern Indians of America. The 

 common house-fly || is stated to have been brought 

 by shipping to our shores, where it had not been 

 s.3en before the arrival of Europeans. The sugar- 

 inito,1[ a native of the West Indies, is now rather 

 common in Europe and America. The violet- 

 colored borer** of the pine, originally indigenous 

 to our forests, is now naturalized in Europe, 

 Jtaviug been carried thither in timber from Amer- 

 ica ; wiiile, in return, we have received from 

 Iheuce another pine-eating borer,ft whose mis- 

 chievous powers render it a formidable assailant 

 of wooden edifices. This insect, we are informed 

 by Kirby and Spence,}]: docs material injury to 

 the ^vooll-work of houses in London, by piercing 

 the rafters in every direction. Its stomach seems 

 to have the insensibility of that of an ostrich, and its 

 jaws the strength of iron nijtpers : for it has been 

 known to perforate sheets of lead, one-sixth of an 

 inch in thickness, with which roofs were covered, 

 lUid in its stomach fragments of the metal were 

 discovered. The pea-bug§§ of America is now 

 found in England and a ])art of the continent of 

 JIurope. The minute-beetle, |||| so common in 

 ship-bread, is a native of Europe ; it is often seen 

 in our vessels, and occasionally on shore. The 

 notorious ])oplar-worm,1I1I a spiny caterpillar, 

 "whose falsely re])uted venomotis jrowers caused al- 

 most the extermination of the Lombardy poplar 

 *onie years ago, is not indigenous to this coimtry, 

 but was ])robably introduced with the tree it natu- 

 rally inhabits, but which it deserts in preference 

 for our more abundant willows and elms. The 

 i\ettle and thistle have brought with them from 

 Europe some of their peculiar insects,*** which 

 liappily are more serviceable than the weeds they 

 have accompanied. It cannot be denied that 

 inauy of our destructive msects are now spread 



* Vcrme^itcs larctarius, L. t Teiiebno moHtor. L. 



} See " A Treatise on BiiOT, by J. Southall." Evo. Lond. 



nso. 



^ Travels, cil. mo. Vol. 11. p. 11. 



II Belknaj), Hist, of N. Hauip. Vol. III. p. 18.7. 



IT tqiisiiui sacchanna. L. ** Calliditm I'iolaceum. L. 



it Callidium bajidum. L. 



ft '•Outlines of Entomology," (3dcd.) Vol. I. pp. 235, 236, 



DOte. 

 ^BnichKS Pisi. L. f] Ancbium pankeum. F. 



ITIT The larva of the Papilio Antiopa. L. 

 *'»»Tho Papilin Atalanta inhabits the nettle, tho Papilio 

 Cardiii the thistle. 



fur and wiile through those sections of tlie Eastern 

 continent which have had commercial intercourse 

 with America ; but it is evident that we have not 

 been gainers by an exchange ; for in this country 

 arc now naturalized immense numbers of foreign 

 insects, whose ravages are by no means compen- 

 .sated by the benefits derived from the Asiatic silk- 

 worm, at this time an object of so much interest 

 to stjitesmen and manufacturers, nor by those an- 

 nually aljstiiieted from the European honey-boe, 

 "the white man's fly," now, through the instru- 

 mentality of our forefathers, swarming even in 

 the We.stern wilds of this c'ontinent. 



It is of the greatest consequence, in devising 

 remedies for the injuries of insects, first to learn 

 something of their economy. Were our insect 

 enemies at all times as apjiarent as their ravages, 

 preventive means might more readily be adojit- 

 cd ; but many of them are not only masked in 

 various disguises duriug the period of their devas- 

 tations, but carry on their ofTeusive operations only 

 in the obscurity of the night, or insidiously con- 

 ceal themselves while performing the work of de- 

 struction. Others, tliough their attacks are 

 made iu broad day-light, and though they may, 

 while thus employed, be constantly exposed to 

 our examination, soon escape from us by chang- 

 ing their forms. These facts show the necessity 

 of learning their habits and changes, if we wish 

 to apply a remedy to the evils they occasion. 

 The transformations of insects arc indeed exceed- 

 ingly interesting in themselves, and are almost 

 without a parallel in the other animal races. 



Like birds, amphibious animals, and most fishes, 

 insects are jiroduced from eggs; but, unlike theirs, 

 the newly hatched young, either have not the 

 same number of members as their parents, or are 

 wholly difterent from them in liirm luid habits. 

 The offspring of rose-bugs and of moths are not 

 rose-bugs and moths ; they are grubs and cater- 

 pillars, which, having been hatched in situations 

 where the parental instinct has discovered their 

 appropriate food, begin iimnediatcly to devour 

 what is before them, and at the expiration of a 

 definite period attain their full size, cast their skins, 

 and appear in a new form. In this new form the 

 insects are said to be in the pupa or chrysalis 

 state. Their former activity and voracity cease ; 

 thtiy no longer use their limlw to change their 

 situation, but remain with tlicm folded close to 

 their bodies in a state of absolute abstinence and 

 almost complete torpidity and rest. In process 

 of time the delicate and tender skin that invests 

 their bodies hardens, the flesh with its new-grown 

 skin, cleaves and separates beneath the old one, 

 and at length the imprisoned insects burst their 

 useless cases, withdraw their limbs from their en- 

 velopes, and, in due season, emerge from their 

 retreats, warm and dry themselves in the sun- 

 beams, and launch upon their untried wings into 

 the air, the exact counterparts of their progenitors. 



The term larva, originally signifying a mask, is 

 applied to all insects in the young or growing 

 state ; to caterpillars, grubs, and maggots, whose 

 future fonns are completely dLsgnised, and to the 

 young of bugs, crickets, grasshoppers, plant-lice, 

 mid some other insects, whose subsequent stages 

 are unattended with any remarkable changes of 

 form. The second state is the pupa; and, while 

 iu this, the insects last mentioned continue to feed, 

 grow, and move about like the larva?, which they 

 also resemble in form. The third or final change 

 developes all in tiicir ^cr/ect state, with new organs 



and propensities. Hence two kinds of transfor- 

 mation are recognised. One of them seems to 

 consist in little more than a casting of the ex- 

 ternal skin, and the acquisition of additional or- 

 gans, with a preservation of the same general 

 form and habits ; this is called incomplete trans- 

 formation : the. other, including an eating, a qui- 

 escent, and a winged state, exhibits insects, in 

 their progress, in three distinct forms, and three 

 different modes of existence; this constitutes a 

 complete transformation. 



A few examples will illustrate the transforma- 

 tions, or metamorphoses, of some common insects, 

 and present a general view of their history. The 

 squash-bug* passes through an imperfect trans- 

 formation. ■ In shape it is, while young, or a larva, 

 proportionally shorter and more rounded than tho 

 perfect insect, and its color is of a jiale, ashy hue. 

 When it enters ujion the pupa state its form 

 lengthens, and two little scales are seen upon its 

 back, which arc sheaths representing and actually 

 enclosing the future wings of the insect. It con- 

 tinues all this time to walk about, and to imbibe, 

 by means of its sharp proboscis, the juices of the 

 plant on which it subsists. In the perfect state 

 it appears with a pair of delicate, filmy ^Vinga 

 folded beneath two tough covers, which lie flat 

 upon its back and cross each other at their ends. 

 In this stage it feeds also by suction upon the 

 juices of the squash leaves ; but, with additional 

 organs, it has acquired new propensities, which 

 lead it to provide for the continuation of its 

 species, and, this being accomplished, it perishes. 

 The transformations of grasshoppers also are in- 

 complete ; young and old, larvse, pupse, and per- 

 fect insects being alike active, and partaking a 

 common food. 



The following are instances of complete metn- 

 mor|>hosi9. The white grub, which is so often 

 turned up by the plough in fields, lives beneath 

 the stirface of the soil, and feeds upon the fibrous 

 roots of the grasses. It afterwards becomes a 

 piqia, exhibiting a form intermediate between that 

 of a grub and a beetle ; legs small and useless are 

 visible, a ]iair of eyes, and two little horns or an- 

 tenna". For some time it remains at rest in the 

 earth, till, ils appointed .season having arrived, it 

 bursts the filmy skin that enfolded its body and 

 limbs, digs itself a pas.sagc to the surface, and 

 comes forth a chesnut-colored beetle,* commonly 

 known here as the ilorr-bitg. In this, its last and 

 winged state, it devours the leaves of trees, seeks 

 its mate, and deposits its eggs in the ground. The 

 whole generation of dorr-bugs perishes within six 

 weeks after emerging from the earth in the beetle 

 form. 



The borer of the apple-tree, a white worm, or 

 grub, devours the fragments of wood it has gnawed 

 in making its cylindrical path within the trunk of 

 the tree, and pushes the undigested refuse out of 

 the hole by which it has entered. When fully 

 grown it becomes a pupa, which, like that of the 

 dorr-bug, exhibits short, folded legs, wings and 

 horns, of no use to it while within its burrow. 

 Early in June the pupa-skin is ruptured, and the • 

 insect emerges from the tree ly gnawing through 

 the thin covering of bark that protected the upper 

 extremity 'of its hole. Ujion issuing into the air 

 it is found to be a beetle,t white beneath and 

 longitudinally strijied with brown above. In 

 this, its perfect state, it lives only upon the young 



* Coretta orciimthis. Say. \ tSaperda bivitluta. Say. 



t Mdolontha Qucrciria. Knock. 



