132 PESTS OP CANE, MAIZE, AND SORGHUM. 



The caterpillar bores through several internodes of the cane before 

 turning outwards ; as a rule there are at least three internodes between 

 the apex and point of emergence. 



In old canes, the death of the growing point by this caterpillar leads 

 to the development of the buds next to the apex and some distance down 

 the cane. The result is a cane bearing large shoots on the upper half , 

 forming a bunchy top of long green shoots. Such canes are very con- 

 spicuous ; the yield must be largely reduced, the cane instead of ripening 

 normally, having to form shoots at the expense of its sugar contents. The 

 upper half of the cane is also more fit for feeding cattle than for grinding. 

 In young canes, the effect of the attack is to produce a " deadhearfc/'' 

 a single dead shoot which grows no more. 



Before the cold weather becomes severe, the larvae that are full fed 

 turn to chrysalides and remain thus throughout the winter. At Pusa, 

 the first moth was caught in the fields in 1905 on March 9th, probably 

 an abnormally late date. Many chrysalides could be found at that date, 

 though they hatched out soon after. Probably the end of hibernation 

 is a fairly distinct period, most moths hatching out about the same time. 

 The commencement of hibernation cannot be fixed so clearly. Moths 

 were common up to the end of October and in early November. After 

 that none were caught and probably the last had emerged in November. 

 All pupse would then probably hibernate by the end of November, 

 full fed larvae would turn to chrysalides and smaller larvae would 

 feed till the cold numbed them, or till they could in turn become 

 chrysalides. 



The wings, legs, body, head, etc., of the moth are clothed in white 

 scales, the only colour visible being at the end of the abdomen. In the 

 female the abdomen terminates in a dense tuft of brown hair, the outer 

 layer of which is red in the variety intact a. The amount of this hair is 

 extraordinary, and as stated above is used for covering the eggs. The 

 females are larger than the males and may be known by this tuft of 

 hair. Both sexes can be easily found in the field, sitting on leaves of 

 cane or other plants during the day-time, flying actively when the sun 

 goes down. 



As a rule mating takes place on the first night and egg-laying may 

 occur on the second but may be delayed. Moths do not all emerge with 

 the eggs fully developed; dissection of reared moths shows that in some 

 the eggs are not so fully developed as in the majority and such moths 

 probably live a day or two longer. 



The number of eggs actually laid by moths cannot be accurately 

 ascertained j even under the best conditions in captivity moths do not 



