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the Tcnebrionids, TriboUum castaneum, Hbst., Latheticus oryzae, 

 "\\'aterh., and Alphitohius piceus, 01. ; the Curculionids, Calandra 

 oryzae, L., and C. granaria, L. ; Lepidoptera : Sitotroga cerealeUa, 

 Oiiv. 



By far the most important of these are A. undulafvs, R. domimca, 

 and C. oryzae, as these species alone damage uninfested wheat ; the 

 others attack grain which has already been damaged by other insects, 

 or their attacks on sound grain are of no importance. The life-history 

 and distribution of these three species in the Punjab and their effect 

 on grain are given in detail. 



A. undulatus has four generations in a year. The adult does not 

 ■damage the grain, but the larva is a voracious feeder, passing through 

 as many as ten successive moults and feeding directly after each. They 

 are generally found near the surface of the wheat, and render the j)art3 

 of the grain that are badly infested hot to the touch. These larvae, 

 unlike the adults of R. dominica and C. oryzae, consume all the material 

 they gnaw from the grains and consequently wheat attacked by this 

 beetle does not become mixed \sT.th the floury matter that characterises 

 the attacks of the other two insects. The frass produced consists 

 almost entirely of excrement composed of small whitish pellets. The 

 larvae were found to be unable to penetrate into entire grains until 

 after the third moult. 



R. dominica is the only grain-attacking insect which is ever observed 

 on the wing. There are probably five generations in a year. Both 

 larvae and adults attack the wheat, reducing the grains to a mass of 

 flour, which probably forms suitable food for the young larvae. These 

 larvae were found to be unable to penetrate entire grains, though the 

 smallest crack or abrasion in the pericarp, due to the work of the adults, 

 enabled them to do so. 



C. oryzae is the best-kno^^^l grain pest in India and has already 

 received much attention from entomologists. As in the ease of 

 R. dominica, the most noticeable effect is produced by the adults. The 

 eggs are laid, not on the surface of the grains, but inside the pericarp, 

 which renders the damage by the young larvae, feeding inside the grain, 

 very difficult to detect. The generations average three or four in a 

 year. The adult damages the grain by piercing the pericarp with its 

 proboscis. 



Attacks from one or other of these species seems to be continuous 

 throughout the year. A. ■undidatus is the most capable of with- 

 standing adverse conditions, while R. dominica and C. oryzae are 

 more prolific. Notes on the life-histories of the less important species 

 are also given. 



Infestation most probably arises from the insects already present 

 in the cracks and crevices of the storehouses into which the w^heat is 

 put, but, as all these insects are winged, it is possible that they may 

 enter the storehouse by flying. 



The authors have carried out a series of careful and comprehensive 

 experiments in order to determine the best method of control. For the 

 purpose of these experiments wheat was placed in thin galvanized iron 

 bins, which are always greatly preferable to the earthen floor of the 

 mud hut that constitutes the usual storehouse in the Punjab. The 

 former methods of control are reviewed, experiments having been 

 made to test the efficacy of all of them. The results of these are given 



