INSECTS AT WAR.

Dominion, Volume 2, Issue 333, 21 October 1908, Page 3

INSECTS AT WAR.

THE CODLIN MOTH'S ENEMY. HOW IT SLAYS. NEW ZEALAND ORCHARDS THAT . 'CONTAIN IT. : • .These queer-looking creatures are desrecent insect'immigrants:- Their name 'is•.otiliephisites' messer. 'They' are strangers in •a. strange land in New Zealand, for the haunts of their forefathers'wire in Southern Europe. Th'ey were' brought here by the New. Zealand Government two 'years the .benefit of'the; fruitgrowers,- to destroythe, mutual. enemy, the codlin moth. This v task"they.;performwith. a 'vim that is peculiar to; many predacious"inYet" there are few : iinsects in the world .that-so-delight' in' : slaughter'-as 'does ' caliephialtes.. !i .'• ? ' *.. The Lady Who Works. • " lit is" "lady • who does,. ail tlie . work. In this' .the;.habits ~of the race, resemble those, of some uncivilised'human beings ; and similar, habit's have on occasion been recorded even'.among white people. She slays with", the!.cruel-looking"long ispear. attached to, her,'posterior; '; Entomologists call-it, an ovipositor.; most "other/ people call it a' sting. She is an interesting .creature, to. .watch when she is out on the' warpath.\ Glistening in the sunlight," trembling with excitement and expectation, she rtas. along the scarred trunks of old , apple trees ,or on Mother surfaces which her instinct' says . may. harbour codlin moth .grubs, searching for her natural preyl And she shows such haste that you would imagine she was searching frantically for a. lost, child, instead of a helpless," harmless codlin moth <grub.\ ...'.. ' Strange. Warfare.:... ; When she discovers her prey she, stretches her'long body, takes aim. with her vicious looking, spear, and drives it through the unfortunate -victim. '■ She: enjoys the-sensa-tion.': obviously, for she often slides; .: her spear.. Then,, with ' a queer little quiver of the body,' she 'finally "withdraws./ her Bpear, and the body of the poor codlin grub contains a caliephialtes egg. - The codlin body, henceforth is-but an incubator to hatch that egg and give forth .the progeny to the world. ■ ' Something About Stings. - , ■ Caliephialtes is really an ichneumon .fly, much smaller than 'shown .in the -sketches. The--length 1 of; her body< is about; t.breeeighths of an inch,. and her- stingj is about the .-same length -in .addition,,. ginug her-; a total llength j from." nose ,to bayonet, point iof "of an inch 1 . , . . Only .' the 'female has the stingl- .' The sting, or : ovipositor,. is just an instrument for depositing eggs into suitable hatching places;.' And. : frugal ' nature has ■: not ' con--sidered'-.it necessary --to"-waste one on the male. . .' So;the male caliephialtes,' if .one could catch him, : could bo caressedand teased'ahd handled iwith- impunity, just- as

his ootisinfl the drono bees can be handled, ■ which ..have no sting. But a's -for the-female; with "her sharp ..little '.instru'mentF-give her a wide berth.' Luckily she is too. busy to attack anything'but grubs. ' An Interesting Existence. /' She. has a..most interesting , existence. Let us ; follow: up the ' process < "from the egg which was - laid during- the act of. .stinging, and/wateh , the . little offspring until'.it be-; comes: a 'winged' fly in its' turn. The egg' . which;,, is . left; inside , the . soft .wet ; body, of, the codlin grub-is warmed,.by the..warmth; . of the -tissues, around ,it, ; ,,and, steadily velops./.', ■ .The . codlin - accommodatingly : lives' on ; stupefied perhaps-r-fpr. sPnie predacipus insects inject a'drug when they, sting, just • as the jinason- bee . drugs "the ' spiders , it catches .and' imprisons with 'its ' baby. : offspring in the mud nest it makes in -your keyholeI—but1 —but certainly not dead. ■ In any case, the codlin grub,, in its winter mummy, case, is a quiescent object 'at its liveliest. So 1 , between, its natural sleepiness and,,the possible drugV and, the stillness of the unmatched egg, matters progress- faveurably— for tho'egg—till hatching time comes, a few weeks hence. " : A "Strange Awakening. Then a: little maggot emerges from tho egg-shell. -It awakes in a queer World—a world bounded by the skin of the codlin grub';- but a world full of food. Doubtless it pokes its head' inquisitively among -the grub's' most 'treasured. vitals for a"fort- seconds,' and' then tho wild appetite characteristic of .the' maggot" life takes possession,' and it feeds'to repletion. At first it care-, fully avoids "wounding. the vital ; parts, * for. that- would kill its' host and cause its food supply to -decay.'.. "What' instinct;!- Depraved perhaps, and cruel, but still 1 wonderful.- • Then-at'-last it has nothing'left to eat but; vital' organs'; so it sots to and empties the 'shell. ■' ' . .. . The . Sleep Time. . Now it is . sleep time. . This, caliephialtes maggot has lived the eating .stage, of, its life,"and like the codlin grub itself, whom.it has slain, it must now sleep the Sleep of-the /chrysalis. ' But it does not for that purpose emerge from the mummy shell of the codlm. These are cosy: quarters' in which it can nestle snugly and dream undisturbed visions of the winged lifo that is. to - come. -But thero' are 'dangers. .Will it. pass through this stago unmolested?, or may not some enemy of an enemy—a beetlo perchance, or a spider-discover its hiding-place, and drag it forth for food? . Or, perhaps, a member of another family of ichneumon flies; at-dag-gers drawn with the caliephialtes household, may probe down into it with a. spear as sharp and'as egg-laden as that of its reveredmother. If that catastrophe befal, then the little mummy of caliephialtes will in its turn become a living iiicubator, hatching tho young of its hated enemy,.- nourishing it 'v/ith its lifo juices and its vitals, giving it a- case to shelter : it from cold' winds' and cold cruelties. Then indeed will the'wrongs of the poor codlin be avenged..

The Next Stage. '".But perhaps none of these things will happen, and the span of sleep comes safely to.the awakening stage. Then caliephialtes, junior, stretches herself, breaks a great rift in the back of her worn-out covering, and becomes liberated, a moving fly inside.thd oodlin shell. Her next task is to make a way to the light beyond: this is; probably easy. And then at last in "the' dazzling sun she stretches hor legs, gives massage to'her wings,- and otherwise prepares for the' flight of matrimony which is now her due. Strange Matlngs. Nature has strange fancies. While some creatures have many wives, there are others —the wise men tell us —that put numbers on the' husbands' side. And caliephialtes is one of these. . Sho will have many lovers. And they may all be faithful, and yet, be sufficient in numbers to pay. multiple court to the rest of her sex, for her brothers outnumber, many times over,- her sisters. An Egg-laying Contest. She has now but one task in life. Sho has eaten, she has' slept, she has been married. She will now "replenish the earth, j She is filled with the spirit of the assassin, j and .at every spear-thrust she will sow the seed of a successor. - She. will carry , the ■ instrument of death &mong the codlin grubs. She probably has no moro recollections of hor former'life'in a-grub than have we of the time when—they say—we were rats. But instinct takes her hack to the old haunts, and ' she . spears ravenously. One hundred and fifty codlin grubs are her life's portion, and if she .sucoeod in finding thait number ■ she has an egg for. each. Her _egg yield is better than that of a barndoor, fowl. Thus she sows the seed of her next generation 150-fold. ■ ■ And 150 -less moths next season will .ruin." the farmer's apples. , The first Arrivals. It is a great business—this strife of insect against? insect. The' "natural enemy" is a great* friend, to- the -pest-ridden farmer. But it -cannot- do all. ~Without, the.-codlin grubs there "can be no caliephialtes'. It can therefore'subdue,, but it' cannot totally' eradicate. ■ Well,- we will' be. thankful fo • the subduing!'" V. • • ■ The flies here . illustrated were sketched at work by-our artist in the Government insectory'at Auckland, by kind permission. of the biological staff.' They \yere hatched :n confinement' from codlin grubs' ' imported from California, where Compere, v the; great insect hunter, of Western Australia, had established breeding colonies from the specimens he gathered in Europe. ■■ L" Orchards that have the Insect. ■Sine©' that time the insect descendants of the early- immigrants have been distri-buted-in i many. orchards- of New, Zealand, whence they will ho .doubt this.season spread to' all parts lof the. Dominion. With 1 caliephialtes and'the 1 spray pump the codlin troubles of.'tho orchardist ought to be small in' the-'futuj-e: .

Here arejthe orchardists: who had supplies of.the ichneumon fly, to "liberate

Avondale:. J. Armstrong, - J. Boliardj E. ,J. Cairns."/; ~ , Albany: W. Boyd, v '' '! Ara'mohp: • Benefield. ' ;' ' Aratiatia: T.. B. Leaman. - '■ Birkenhead:„W.. Charman, Guminer Bros., 'T. Horton, E. Edmonds, J. G. Kay, J. Levesque/Rich Bros.", B. V S. Bedford. . ■ ChristchurchJ. C. 'Blackmore. : Cambridge: J. Sharp. < Drury: J. Dickson. . Dargaville:, H. Dunn. ... - Frimley : W.H. Smith, J. N. Williams!'. • ! Gisborne: J. Ci Hardy. ■ Greenhithe ,f'T.. r Huriter Hastings: 'El*. H. Williams'. • Helensville: H. Hjorth.■-. , , ■'Henderson :• J. Houghton, T. Roberts, G. W. Rogers, W. D. Stewart, G. Sheffield, Busconibe, Piatt. . . , . ... ■ "Hunterv.ille : Blundell.. ■ Kawakawa:'N. May. Mangaiti : F.' M. .Strange. New Plymouth:' Newton King'. , New Lynn: Morgan'.. Otago Central (Tarras) : J. Collings, junr.Otahuhii:' F. LiGatt. : Ohaupo: Andrew" Karl, C. Rayner. Oratia: T. R. Cox, J. Parr, Stuart. Omokoro: Hutchinson and Miller. Palmcrston North: Miss H. Hearn, Pickering. >. Ponsonby: L. H. Keals. . Puriri: C. M'Liver. Pakiri: J. B. Witten. : Port Albert: B. M. Gubb. Roxburgh (Ashgrove): J. C. Pennel '. Rawene: A. Ward; H. Pearson.' : St. Helier's: E. Yellcnoweth. • Te Aroha: J. Rougen, Shrirhpton. Tauranga: E. Clarke. : : Tuakau: J. Collins. Teviot: J. Tamblyn. ■ ' Takapuna: J. N. Young. ■ . Whancarci: J. E. Ewing, Hoey Bros., A. J. Hill, M. Hutchiiigs, W. Mitchell, D. MacMahon, 0. Woaver. • Waiuku: E, M. Ellin. Warkworth: Mrs. Goatley, Morrison and Sons. ■ Woodhill: R. Monk. . ,-Waik.iimete: T. Parr, E. Parr, H. Sharp. Waihou: Hugh Ross, W. A. Taylor. Wado: D. Roberts. ■The Sketches. ■ The illustrations show (1). caliephialtes; female,-• -with the: clastic ovipositor' drawn' into a loop for -exorcise: (2) another- form of exercise, the sheath - split - open; (3) a little, massage ajong the abdomen does no harm ; (4) .searching 'for codlin grubs; (5) a discovery:; observe the antennae prospecting in the hole; (6) taking aim at a codlin grub; (7) the thrust.