288 



Ser. A, vii, p. 114]. The method by which infestation is carried 

 over from season to season is not known, nor have preventive measures 

 been discovered. 



Most of the stem-borers in rice hibernate in the stubble, while 

 ScJwenobius incertellus {bijmnctifer) can be destroyed in the larval 

 stage by ploughing the stubble early in March. Spodoptera mauritia 

 was completely checked in many localities by the kerosene method 

 described in the preceding report [see above]. A widespread attack 

 of a beetle, Hispa sp., was successfully checked by the use of bags. 



In addition to the sugar-cane pests mentioned in the last repoii;, 

 nine other borers not yet known to occur in sugar-cane have been 

 found in wild grasses and are considered to be potential pests of it. 

 Thick canes are more liable to attack by borers than thin ones. 

 Experiments at Pusa show that the cutting away of dead heai'ts and 

 dry plants with insects in them, which is the treatment usually 

 recommended, retards the proper growth of the cane and is therefore 

 useless. 



The Longicorn beetle, Xylotrechus quadripes (coffee borer), is being 

 controlled in Mysore by scrubbing the plants twice during the period 

 of emergence of the beetle. In the course of experiments to find a 

 simpler remedy, applications of Brunolinum, a crude distillate from 

 coal-tar, as late as two months after hatching, have been entirely 

 successful, and no injury to the trees has been noticed. Applications 

 made only to the ridges round the stem by means of cotton-wool 

 soaked in this substance also proved quite successful. Experiments 

 will be made to determine whether its application before the emergence 

 of the adult beetles will kill them. 



In Mysore, mango hoppers [Idiocerus] were found to be largely 

 influenced by temperature, and it is hoped that this discovery may 

 be of practical value in their control, especially as the cost of spraying 

 is excessive. In the Punjab, a Coccid, Monoplilehus sp., is a serious 

 pest on mango blossoms ; bands of cotton wool or grease bands of 

 crude vaseline and rape oil on the trunks have been found effective 

 against it. In Bengal it has been discovered that the mango weevil 

 [Sternochetus mangiferae] lays its eggs singly in small depressions 

 on the half -grown fruit, covering them with a black substance. This 

 knowledge, combined with the evidence that the oviposition period 

 is limited to a week or two, ought to render remedial measures 

 practicable. A Psyllid, Euphalerus citri, was controlled on citrus 

 trees by regular spraying from March to June with crude oil emulsion 

 and tobacco decoction. 



The method of storing grain under a layer of sand was found to 

 be efficacious in protecting it from insect pests. Tribolium castaneum 

 is found to do no injury to sound wheat, but breeds profusely in 

 the dust produced in wheat already affected by Caiaiidra sp. and 

 Wiizopertha sp. Bruchus chinensis, which is a pest of stored pulse, 

 is able to breed in the field at Pusa in cow-pea pods. B. affinis 

 infesting pea seeds has been considerably checked by drying the 

 seeds in the sun for seven days, even if they are stored for a year 

 afterwards. The treatment of wood infested with termites by soaking 

 in arsenicals or creosote or wood-tar is described. 



The condition of the silk and lac industries during the year is also 

 reported on. 



