\ 



320 



and therefore ineffectively, whereas the dipping method with a solution 

 of carbolineum of a strength suitable for the particular variety is rapid, 

 efficient and inexpensive. With regard to wind carriage, the author 

 thinks that this is not only theoretically possible in the case of the 

 very young larvae, but that it actually occurs. A planting of young 

 canes cleaned with petroleum and rendered, as far as it was possible 

 to be sure of it, free from scale, stood at a distance of a little over a 

 yard from a block of one year old Kasso cane, heavily infested with 

 scale. About a month after the sets had been planted the young 

 plants were found to be infested above ground on the leaf sheaths with 

 very young scale larvae, and the position of the larvae and their 

 distribution among the plants clearly pointed to infection from the 

 Kasso, as it extended about 10 yards into the young plantation ; two 

 months later a further quantity of very young larvae were found on 

 the short stems. The author is more or less satisfied that these young 

 larvae were wind-borne. Secondary infection or the spread of the 

 scale through a plantation may arise from the same cause, especially 

 among the tops of the canes. In conclusion, it is urged that, owing to 

 the rate of propagation, especially in January and February, this pest 

 should be closely watched for and the infested plants destroyed at 

 once. 



WooDHOUsE (E. J.) & DuTT (H. L.). The Campaign against Surface 

 Caterpillar at Mokameh in 1913. — Bihar & Orissa Agric. Jl., Patna, 

 ii, 1914, pp. 16-35,2 maps, 2 plates. [Received 30th March 1915.] 



The authors' previous success with the Andres-Maire traps seemed 

 to make it certain that the spread of the moth in the district would be 

 checked by the use of 25 of them. This paper is a minutely detailed 

 account of the operations and the local conditions prevailing over the 

 low-lying, periodically flooded area at Mokameh, known as a tal. In 

 one place there was evidence that the moths escaped from the traps 

 and investigation showed original defects of construction, which were 

 successfully remedied by placing horizontal strips inside the slits and 

 the use of a sticky liquid on the inside of the framework of the trap. 

 By the middle of November the catches suddenly began to increase 

 enormously and continued high throughout the month, and the traps 

 were kept in position till the end of January when the first parasitised 

 caterpillars were found. The damage due to Agrotis ypsilon is put 

 at 37 per cent. In 1912 the dates of the three broods were September 

 5th-1.5th, September 2.5th to October 20th, and November 1st to 

 December 15th and the catches in thousands 3, 55 and 76 respectively. 

 In 1913 the date of the first brood was not traceable, but the second was 

 from October 5th to November 5th, the third from November 13th 

 to January 10th, the catches in thousands being 49 and 794 with 35 

 traps in use against 25 in the previous year. The great differences in 

 the figures for the two years are largely explained by local conditions, 

 but it appears to be more or less clear that the bulk of the damaged 

 areas were outside the areas protected by the traps. The attracting 

 liquid, used in 1912, was composed of gur 65 per cent., ethyl acetate 

 0-6 per cent., water 34 per cent., and alcohol 0*6 per cent. ; this was 

 found to be too sticky, and a mixture of equal parts of gur and water 

 with the other ingredients was substituted and gave equally good 



