1118 



PRACTICE or ACUK ir.ri RE. 



Ml. 



7689 Tke A'phide* or i>i-u>t lice, next t * » locusts, ere the most universal devastators of the vegetable 

 worid: almost every plant has its peculiar species; their fecundity Is so prodigious, that Reaumur has 

 calculated that In Bve generationi one Ophti maj be the progenitor of 5.9O4,9U0 f UOU descendants: and 

 it is supposed that In one year there may be twenty generations! Those which attack the different kinds 

 of grain seldom multiply io ti-t ai to be very injurious; but those oeculiar to pulse increase rapidly, 

 ami take such possession, that the plants are greatly injured and frequently destroyed before the -seeds 

 are matured. 



Thrse i merit art eynilltf iujurivit in their 



id in (It- ii Lie raor iptBKIIISlUUC (»»»m ig' 



i a in.ii.nir b i .i iparrowi and other blftu 



Inged 

 ipnsnui itate ■" m 



97 -'• /miiT'iLiil anil 



■ 



whooeatroy w I to other deadly 



■ad era snamli l small hymenopteroua Insect, 



which deposits lu egg m tin- both ; it b there hatched t su 



upon the Lntesdni ■ . In -i ihon unn the A*phls swells, I i 



hard i ami ,from tx Ing Bjeen, chsflaefttoadarfc red colour. The 



an till ilc troter within, when he finds hie victim dying, eati .1 



. ii i<L fastens the A'phls, bj that part, to a 



leaf ot t» ljt< W ban the paraaite h is thus devoured the inside, 



ami i% i e< i. he opens a passage 



uttingoul i round hole in the side, leaving the 



on its binges, adhering to the Uodj m . 



Hui the most Inveterate and destructive (be to the plant-lice is 



the lady-bird or tady-e « I oo inelia £.., jffg-. 974. a), which, 



in it-> larva state [b), feeds entire!) upon these insects; and 



the havoc nude i ng them may be conceived, from tiie 



myrtadi upon in.ri.nl- of these pretty little creatures which 

 an- osuaUji seen m yean when ihe plant-louse abounds; 

 ever> one, probably, destroying tern of thousands of Aphides 

 before be bec om es ■ beetle. On this account the lady-bird is 

 the greatest friend to the gardener and fanner ; and could there 

 !►.- .iii% method devised of increasing these useful insects -it 

 will, our hot-houses, gardens, fields, and hop plantations, 



■ mi be Cleared from the ravages of plant-lice. The 



974 



larvae of several bee-like tin-. Syr> 

 phni /•'., c) are no less useful in 

 this respect Ti eir form reey much 

 resembles that <>i the leech, having 

 no apparent head. Some rpeciea 



ii, with a white stripe down 



the middle; others brown, variegat- 

 ed with <l jrker sh des< Tbej are 

 always found upon those'ptants most 

 Infected by Aphides, upon which 

 they solely depend for nourishment ; 

 hence they become mo I benefit lal, 

 and should on no account be de» 

 stroyedi As palliative measures, 

 the application of powdered quick- 

 lime may be reported to; or the in- 

 fected shoots may be topped ort"before 

 the insects are greatly multiplied, 

 repeating the same operation hi fore 

 the time that the winter stock of 

 e^ffs are depooited. By the first 

 pruning a very numerous present Increase will be prevented ; 

 and by the second, the following year's breed may, in a great 

 measure, be destroyed. {Phil. Trans. 41. p. 181.) 



*768*. The wire-worm is a name that has been given, without discrimination, to the larvae or grubs of 

 various insects, totally different from each other : hence it is, that much contusion and contradiction will 

 be found respecting it in agricultural books. The true wire-worm is the grub of a small beetle (E'later 

 segetis Marsham), and it derives its name from its slender form and uncommon hardness. It lives in the 

 larva state nearly five years ; during which time it is supported by devouring the roots of wheat, rye, oata, 

 and grass, winch it attacks indiscriminately, and causes annually a large diminution of produce : it 

 abounds chiefly in newly broken-up land, and is particularly destructive in gardens recently converted 

 from pasture land. In the larva state it may be decoyed by offering it more tempting food , but no method 

 has yet been devised for destroying the perfect insect. 



768& The grub is a general name for several larva? of crane flics (Tlpuladffi), called by the country 

 people long-legs, or gaffer long-legs. 



/686. One of if it most destructive amone these insects to the 

 roots of grsss and grain is the Tipula oleracea. The larva is 

 said, hy unite anthers, merely to loosen the roots b\ hurrov. ing 

 among them : but others assert, that it likewise feeds upon the 

 fibres. Ho* aval this may be, the evil produced is evident ; for 

 in many p »rts of England it cuts oil" a laru'e proportion of the 

 peciaJh it" sown upon clover-lays. Reaumur 

 inform-, ns, thai ometimes In Prance, partlcularW in marshy 

 lands, the grass of whole districts has been sodestrnved by it". 

 a> n..t to produj a the food n< nonary for the mstenance of" the 

 cattle. No effectual remedy has vet been discovered for this 

 evil ; and M . kn.-y observes, lh.it the insect is not killed hy 



lime, even when applied In much larger doses than usual. 



.'»s,. Thrrr art several filler tpecirs of a large si/,-, as the 



rrpul . . r.f ha ft u >. <i;.'i. <j . ind nptua rivoea e , which, in a 

 I' sil.grw, are also injurious to such lands as are nu>M and 



IswArr MtfiMtfc species U particularly dettrnctlve to 



corn, And U g«-nrrally known a. thcwln-.it 11 % ZTpolatrfUci] ft); 

 " hi t omj has been abl] mveangated by .Mr. 



M.ii hun and Mr. Kirby. The Injun Brsl appears in the 



ral of which, on being opened, wtll be found I ntaln 



an onnge-t oloured powder; In this are concealed very minute 

 lame (jr), whu h. on i- ngraa nlfii sen to be thick 



at one end, extending and ..-mr.u ting th< n . K. . .u , 



and frequently jumping half an inch at one spring ; they tate 

 their station in the longitudinal furrow of the grain, and by 

 sucking its milky juice causes it to shrink up, and become 

 what the farmers call pangUd: the last sown wheat always ap- 

 pears the most infected. In the beginning of June the per- 

 fect insect (/>) may be seen in innumerable multitudes, flung 

 in the evening in all directions over the corn-fields; hut during 

 the day not one is to be perceived. The female lays her eggs 

 {J e magnified) by means of a retractile tube, which encloses a 

 vi rv li'ii^' and acute sting resembling a hair ; but this can only 

 be distinctly seen when the insect is magnified (h). The wheat- 

 fly would soon become a formidable enemy to mankind, were 

 not its race exposed to an inveterate foe, scarcely larger than 

 themselves ; this is the ichneumon 1 "puhe, the female of which 

 carefully searches out the grubs of the wheat-fly, and deposits 

 in each one of her eggs : these arc hatched, and ultimately the 

 larva devours the body which gave it life- One ichneumon 

 will thus cause the death of many dozens, and prevent the fu- 

 ture multiplication of thousands." The only palliative that has 

 been recommended for stopping the progress of this insect has 

 originated In Mr. Kirby ; this consummate naturalist thinks 

 much benefit would be derived hy fumigating the corn with 

 tobacco and sulphur, when the wind is in a favourable quarter : 

 ihs must be done as soon as the ear begins to shoot from the 

 leafy stalk. [Linn. Trans.) 



Subsect. 5. Insects injurious to Food, Clothing, $c. 



7C&9. The manufactured product qf our fields and gardens, whether as food or clothing, is still 

 exposed to the ravages Of Other tribes Of inserts, which take up their residence in our dwellings, and on 



every thing about us. Fortunately, however, these domestic enemies are much less numerous and hurtful 

 ID fhis coantrj than in the tropical regions of America, India, and Africa, where their devastation is 

 almost Incredible Amongst the few that arc indigenous, or that have been naturalised in Britain, the 

 principal are the cock-roach, the house-cricket, and the bacon-grub. 



