234 JOURNAL. BOMBAY NATURAL HISTORY SOCIETY, 1891. 



through in the year. Two or three of these generations take pi ace 

 between the reaping of the rice of one year and the springing up of 

 the succeeding crop in the next year. These intermediate generations 

 are said to be passed in the self-sown rice and big grasses whic h 

 spring up in and around the rice fields. In this pest therefore we find 

 an additional reason for encouraging the keeping down of the growth 

 of rank grasses around rice fields. 



The next slide is intended to represent the Variolas phases 

 in the history of the maize borer, which has been sent to me, 

 by the Secretary to the Municipal Committee, Am ritsar, as responsible 

 for the destruction of what has been variously estimated at one-sixth 

 to one-tenth of the maize and millet crops around Amritsar last year. 

 This insect is, so far as we at present know, the same as the one 

 which is so often destructive to sugarcane. It damages the stalks by 

 drilling: holes in them, the result being that moisture finds its way 

 into the stalk and sets up putrefaction, which in the case of both 

 sugarcane and sorghum, is of a particularly offensive nature. The 

 tnsect is referred to by Duthie and Fuller, in their admirable work on 

 field and garden crops, under the name of salai or nihil when it 

 attacks maize and sugarcane, and under the name of bhaunri when it 

 attacks sorghum. In the case of sorghum the morbid putrefaction 

 which it sets up in the stalks is said to render the plant poisonous to 

 rattle. The moth lays its eggs at the base of the leaf sheaths and 

 the larvae tunnel into the stalks, where the chrysalids are also found. 

 Several generations are gone through, in the warmer months of the 

 year ; and the insect passes the cold weather in the caterpillar stage 

 in a dormant condition in its burrow in the stalk. Old cane stalks 

 therefore are the most fruitful source of the spreading of the pest, 

 and anything that tends to keep the old stalks away from the grow- 

 ing crop must likewise tend to reduce the evil. This insect attacks 

 sugarcane in all parts of the world, and very numerous remedies have 

 been tried with a greater or less measure of success. But the only 

 measure which seems to be universally recommended is that of keep- 

 ing the fields clear of all old stalks and cane trash, in which the 

 insect would otherwise find shelter. It may be noticed that this 

 insect occurs chiefly in dry seasons, and that some varieties of cane 

 are more subject to it than others. The explanation which has been 



