9 



lowing:'- Hprino" ill time to ovipo.sit on yonu^ corn. If, howcv(n', tho 

 uulumii is WMi'iii, !i sniull pi'oportioii of the piipju iii;iv triuisi'onii t(j 

 iiiotlis, which oviposit aj^-aiii on cotton, and a few boll worms are thus 

 to be found in cotton iields until the plants are destroyed by frost. It 

 is sii})posed that a few of the late-ap})earino' moths may liibernate as 

 such durinj^ the winter, and henc(5 appear early in the spring', thuh 

 addinj^ to the confusion of generations, but the evidence on this point 

 is fai- fr-om satisfactory. 



THE BOLLWORM ON CORX. 



Corn is, without doubt, the preferred food of the bollworm, and 

 matci-ial injury to cotton occurs only after the corn has Ix'come toe 

 old to furnish suitable food. A consid(!ratiou of the bollworm on cot- 

 ton, therefore, requires brief mention of its occurrence on corn. 



The eggs are de[)osit(Hl ([uite promiscuously over the plant. On 

 young corn the distr'ibutic^i of (!ggs is <;onfined largely to the leav(;s, 

 and as many as twenty to twenty-five may often be counted on a sin- 

 gle small plant. On corn in tassel and fresh silk, eggs ar(! d(5posited 

 <juite g(inerally over these parts, and the lumiber which may bedejjos- 

 itcul on a single plant is often surprisingly large. 



Notwithstanding the large immber of eggs which may be deposited 

 on corn, only a small pn^portion of the larvte from these ev(;r riuich 

 full growth. Larvai hatching from eggs laid on other parts of the 

 j)hint than the silks will mostly perish in thcnr search for suita))l<i food; 

 vviiile, owing to th(5ir cannibalistic habits, from the numerous eggs 

 deposited b}'^ the moths on the fresh silks, not more than two or three 

 larvic will succmmkI in attaining maturity in the sanu^ ear. CV)rn, in 

 addition to Iniing an excellent trap (;rop to attract moths away from 

 cotton, also s(;rves to reduce the insects in numbers. 



Injury to young corn })y the first genei'ation is confiiKid largely to 

 the " bud,*' and l)ecomes apparent as the more central, ragged,, and 

 shot-holed leavers unfold (fig. 3). It is rarel}' serious in extent. Injury 

 by an allied s{)eci(!s, the fall army worm (La.j//t.//f//n'ffri/(//'jM'/-(Ir/ S. & A.) 

 is often very severe on June corn planted in cai'ly siiimner, and has 

 been (erroneously attributed to the bollworm. Likewise, irijury by 

 the second g(uiei-ation of bollworms is comparatively insignif).?ii,nt, ))ut 

 the third g(;n(!ration, affecting roasting ears, ma}^ be theca»^se of much 

 loss. Injury is not confined to the quantity of kernels of corn eat(!n, 

 which in the aggr(;gat('inust))(! considerable, })ut moreinipv^rtant dam- 

 ag<' rcisults from the molding and souring of the ear, favored by the 

 filthy excrement and exuded milky juices from the injured grain 

 (iig. 4). No practical means, iiside from late fall or v/i<iter plowing, 

 have, as yet, been discovered for reducing bollworui U/jury to coru- 



191 



