112 NIGERIASOUTHERN PROVINCES 



crops into the rotation with cotton. 3. Special efforts to 

 be made in those countries outside the oil palm dis- 

 tricts, where the natives have little else capable of being 

 produced for barter for imported material. After a series 

 of experimental trials it was decided in 1915 to encourage 

 the planting of Georgia cotton in the Western Province. 

 In the year mentioned this American variety had yielded 

 800 Ibs. of seed cotton per acre at Ibadan. 



A number of insect pests of a more or less serious 

 nature attack the plant at different periods of growth. 

 The American boll-worm (Chloridea obsoleta) does some 

 damage annually in the Central Province (Ugboha, 

 Agbede and Ishan) ; E arias insulana, F., the Egyptian 

 boll-worm ; E. imbricata, an allied species, and Diparopsis 

 castanea Hamp., the Sudan boll- worm, are common at 

 Ibadan. The immature boll is often punctured by a 

 scarlet and brown bug, identified as Dysdercus super- 

 stitiosus, Fabr., which enters the opened bolls also, and 

 exudes a yellowish liquid, which stains the lint. The 

 opened boll is also infested with three species of cotton- 

 seed bugs Oxycarenus hyalinipennis, O. gossipinus, and 

 O. Dudgeoni which do a large amount of damage in 

 sapping the juices from the seed and rendering it un- 

 productive. The most satisfactory method of dispersing 

 this insect is to place the seed-cotton in a hot sun for several 

 hours. Both Oxycarenus and Dysdercus may be trapped 

 by placing piles of seed in the field at intervals, and 

 treating them with kerosene when the insects have 

 collected on them. A small caterpillar belonging to the 

 family Gelechiadce * is often found in the boll feeding on 

 the seed, and a leaf-blistering blight, probably Chlorita 

 flavescens, appears to be common in several places. 

 A malady, chiefly on stems of exotic cottons, and known 

 as " black-arm " in Georgia, U.S.A., is seen occasionally. 

 The affection is not attributed to any animal or vegetable 

 parasite. 



The ginneries erected by the British Cotton Growing 

 Association are probably some of the best equipped in 

 the world. The Maryborough Ginnery at Ibadan (Fig. 23) 

 has at present the largest output, although the Jones 

 Ginnery at Oshogbo is larger, arid is expected to receive 



* This has since been identified with Oelechia gossypiella, Sanders, 

 an insect which subsequently effected such enormous damage in Egypt. 



