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COTTON EXPERIMENTS 

 IN THE BOTANIC GARDENS, SINGAPORE. 



During the year 1904, the Botanic Gardens, Singapore, receipted 

 from the Inspector-General of India, a large series of seeds of vari- 

 ous cotton plants obtained through the agency of District Officers 

 in various parts of India. There were about 80 kinds in all. These 

 were planted in the most suitable soil available in the Gardens, and 

 carefully tended. The seed, in most cases, germinated well, but a 

 few strains such as Nagpur, Griffin, Peterkin's Long Staple, Haw- 

 kin's improved, Trint's big ball, and some others completely failed. 

 But, as these we*e nearly all in one set of beds, I attribute this 

 rather to the fault of the soil, than the seed. 



Of this set of Nagpur cottons, the best grower was Bourbon, but it 

 failed to fruit sufficiently heavily. 



Nearly all the plants flowered well, but the fruiting proved a 

 failure, the pods being destroyed by vermin before they were ripe. 

 The Nagpur broad-leaved varieties were more severely attacked by 

 the leaf rollers than were the narrow-leaved forms [Neglectum series) 

 and were also more liable to attack by the red cotton bug, Dysderccus 

 cingulatus. Of the Neglectum series, Braisa and Jalna yellow, made 

 the best growth, but the pods produced were very small. 



Egyptian and American cottons grew fairly well, but suffered 

 badly from pests, and I am inclined to think that the Sea-Island and 

 Upland strains are most suitable for this country. 



I should not however recommend any one here, at least in the 

 South of the Peninsula, to attempt to grow cotton commercially. 

 The number of pests which attack the plant in this part of the 

 country is very large indeed. 



A leaf-rolling caterpillar, and a small boring caterpillar attack- 

 ing the shoots damage the vegetative organs severely. The fruit, as 

 soon as it sets, is attacked by the red bug, a pink moth-caterpillar 

 which devours the seeds, and a minute dipterous larva. These so 

 utterly destroy the fruit that not one per cent, comes to maturity. 

 Many plants though flowering well did not produce a single good 

 pod and of many kinds I was unable to save a single seed, the 

 pods being quite rather long before the seed was ripe. Spraying 

 with insecticides had little effect, Dysdercus destroyed one day thus, 

 was quickly replaced by others which appeared from some more 

 distant spot in a few days. One or two kinds of caterpillar hunting 

 wasps were often at the bushes carrying off the leaf-rollers, but made 

 little impression in their numbers. 



I had hoped that out of the numerous varieties sent from India, some 

 might be found more resistant to insect pests than others, but though 

 the narrow-leaved forms were less attacked by leafrollers than 

 the broad-leaved ones, and owing to their narrower bracts less at- 



