THE PESTS AND DISEASES OF THE CANE. 



STEM BORERS. 



Diatraa saccharalis. The West Indian borer. 



D. striatalis. The grey stem borer of the East Indies and Australia. 



Chilo auricilia. The gold fringed borer of India. 



C. simplex. India. 



Nonagria uniformis. The pink borer of India. 



Anerastia ablutetta. The green borer. India. 



Castnia licus. The large moth borer of South America. 



Sesamia nonagrioides. The purple borer. Java, East Indies, Spain, 



Portugal, North Africa, Madeira, Mauritius, Madagascar. 

 BOOT BORER. 



Polyoclia saccharella. India. 



All these borers have a very similar mode of attack ; the female moth lays 

 its egg on the leaf of the cane ; the caterpillar, on emergence, attacks either 

 the stem, generally at the eye, or else the terminal point, and eats its way 

 into the cane. When in the cane it often tunnels the whole length of the 

 stalk ; eventually the perfect insect emerges from the cane. 



When young cane shoots are attacked, especially by the top borer, the 

 death of the stalk, results ; in older cane, especially when attacked in the stem, 

 the damage may not be so complete. 



The Borers have been studied in great detail in many cane growing 

 districts; full accounts of those that occur in Java are given by Kruger 1 and 

 Yan Deventer. 2 Maxwell Lefroy 3 has described the West Indian Borer, 

 and the Borers as they occur in British India 4 ; Oliff 5 has described the Borer 

 of New South Wales, and Bojer 6 the Borer in Mauritius. 



A short account of the West Indian Borer, as described by Maxwell 

 Lefroy, 3 is appended, as typical of these pests : 



" . . the eggs are flattened oval, and slightly convex, about -^ of an inch 

 in length ; they are laid in clusters on the leaf of the cane, the number being very 

 variable, lying between 4 and 57, and being generally from 10 to 30. The eggs 

 when fresh are light yellow ; in 36 hours a tinge of orange appears, and eventually 

 they turn orange brown ; in the final stage the centre of the egg becomes black. 

 If the eggs are laid on young cane the part attacked is the axil of the leaf or the 

 leaf itself ; in the case of older cane the part attacked is the joint, the caterpillar 

 eating its way into the cane, and making tunnels up and down the cane, from which 

 it eventually emerges in from 30 to 35 days. The period of pupation, which takes 

 place within the cane, is six days, after which the perfect insect emerges. The 

 moth is inactive by day, and living only four days lays in that time from 100 

 to 300 eggs." 



In Figs. 15 and 6* are shown the larva and moth of the Borer Diatraea 

 xtriatalis, and in Figs. 47 and 4$* the larva and moth of Sesamia nonagroides. 

 The eggs of the first-mentioned are shown in Fig. 49* ; at a are fresh eggs, 

 at b eggs just before emergence of the caterpillar, at c and d are eggs parasitized 

 by Ceraphron leneficiens and Chactosticha nana. Fig. 50* shows the quite different 



* See Frontispiece. 



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