IROCEEDIXGS OF THE IHIRD EXTOMOLOGIC^VL MEETING 407 



As regards growth, in tlie middle of April 1917, the plants in the plot 

 planted in November 191G ^Yere slightly ahead of those of the plot 

 planted in February. But the difference in gi-owth did not indicate 

 a difference of four months in planting. The difference disappeared by 

 May. As regards yield the plot planted in November was better than 

 that planted in February. This result, however, cannot be depended 

 upon as conclusive. 



From the two plots of Purple Mauritius all the affected plants 

 examined on the different dates given in Tables I and II were cut out 

 with the insects. No other plot was similarly treated. 



The Experiments of 1918. 



In February 1918 two half-acre plots of SatJii No. 131 were planted, 

 one for treatment by cutting out and removing plants and shoots which 

 were dry or showed " dead heart " together with the insects found in 

 them, and the other to be left untreated as a check. The two plots 

 were in an area known as the Brickfield at some distance from the main 

 sugarcane area of the Farm in Jhilh'. They were practically similar 

 as regards soil and were not contisjuous. having about half-an-acre of 

 indigo between them. This field was previously a piece of wasteland 

 overgro^vn with Saccharum sponfaneum and Tmperala arundinacea and 

 was even now bordered by similar wastelands on the west side, as will 

 appear from the plan. The setts, about a foot in length, were examined 

 by the Entomological and Mycological Assistants against borers and 

 Red Rot. For the treated plot the setts were dipped in lead arsenate 

 solution (lib. of Thompson Chemical Co.'s 40 per cent, lead arsenate 

 in 2 gallons cold water) and dried in the shade before being planted, 

 51bs. lead arsenate being used for about 9,000 setts. 



The setts were planted in furrows made with a plough and, before 

 the furrows were filled up with the harrow, powdered oilcake was sprinkled 

 in them. Both the plots were weeded in the third week of June, powJered 

 oilcake was sprinkled near the base of the plants and their bases earthed 

 up by driving a ridging plough between the rows of plants. No further 

 cultivation was given to either of the plots. As usual with the cultiva- 

 tion of sugarcane at Pusa no irrigation was given. Between the 7th 

 and 13th August both the plots were submerged in water, the water 

 standing a few inches above the ground. The water was pumped out 

 by the 1 3th and 1 4th August but the furrows between the rows of sugar- 

 canes remained full and the soil did not dry or become fit to be walked 

 on before the middle of September. 



Both the plots were examined on various dates, the actual number 

 •of plants and those with " dead heart " or dry being noted, and the 



