182 



beneath it and rapidly turned right side up, the hand being quickly 

 withdrawn and the opening in the tent closed. The gas is generated 

 instantaneously and escapes in jets from the lateral openings. 



The advantages of this form of generator are that it involves no loss 

 of time or of gas, and that it is easily cleaned and is strong enough to 

 withstand rough handling in the vineyards, while the lateral openings 

 utilise the force of chemical reaction to ensure the rapid diffusion of 

 the gas. 



DuTT (H. L.). The Greasy Surface Caterpillar: its Life-History and 

 Seasonal History. — Agric. Jl. Dept. Agric. Bihar & Orissa, Patna, 

 V, no. 1, April 1917, pp. 1-14. [Received 2nd March 1918.] 



Agrotis ypsiloti (greasy cutworm) is a pest of major importance 

 damaging tobacco, potato, pea, wheat, gram, lentil, mustard and 

 hnseed crops [see this Review, Ser. A, i, p. 507]. The length of the 

 incubation period is influenced by temperature and moisture, varying 

 from 2 days in April to 4-6 days in the winter months, when the chances 

 are more in favour of trapping the adult before oviposition. The 

 larvae can be reared experimentally on maize, sugar-cane, cucurbits 

 and cassava in addition to their usual food-plants. The larval stage 

 varies in length from 19 days in summer and the rains, to 47 days in the 

 coldest months. When in large swarms the keen struggle for existence 

 compels them to abandon their habit of feeding only at night. The 

 camiibalistic habit, for which this caterpillar is notorious, increases 

 with its development, being quite absent in newly-hatched larvae. 

 The pupal stage, which varies in length from 9 days in April to more 

 than a month in December, is passed in a smooth hard earthen cell, 

 quite imperceptible in hard clay soil, and only slightly in evidence in 

 loamy soil. The adults, which are nocturnal in habit and have a 

 marked repugnance for sunlight, are more active in moist than in dry 

 weather. Under insectary conditions the length of Hfe of a female 

 moth varies from 10 to 14 days, that of the male being much shorter. 

 The adults emerge during August, reach a maximum in December and 

 finally disappear some time in April, apparently aestivating in the 

 adult stage, probably in thatched huts or in buildings of villages 

 adjacent to the low flood-lands. 



The pest is best controlled by means of Andres-Maire traps and by 

 hand-picking the first brood larvae [see this Review, Ser. A, iii, p. 321, 

 and iv, p. 418]. 



Studies are now being made of two Hymenopterous and one Tachinid 

 parasite, an account of which will be published as soon as the work is 

 completed. 



b 



Mackie (D. B.). Some Causes of the Failure of the Manila Cigar on 

 the United States Market and a Remedy. — Philippine Agric. Rev., 

 Manila, x, no. 3, 1917, pp. 223-252. [Received 2nd March 1918.] 



The most important enemy of the cigar manufacturer in Manila is 

 the cigarette beetle, Lasioderma serricorne, which is more prevalent in 

 some years than others. 



The microscopic eggs are laid singly in wrinkles or folds of the dried 

 leaf. The larval stage lasts 151 to 170 days. Pupation takes place 



