183 



There is a well-marked form of the Sea Island cotton to which To- 

 daro gave the varietal name of polycarpum, to which is usually re- 

 ferred the Bamia variety of Egyptian cotton. It is principally char- 

 acterized by numerous flowers springing from a single axil, and an 

 erect, slightly branching habit, hence giving a large yield per acre. 

 On poor soil it soon degenerates to an ordinary form of Sea Island. 

 This is considered by Sir J. D. Hooker* as a well-marked seminal 

 sport, with a fastigiate habit, from some kind of Egyptian cotton, the 

 bulk of which belongs to the Sea Island form of G. barbaclense. In 

 one of the Kew Reports! the idea that Bamia is a hybrid between 

 okra and cotton is shown to be incorrect. The cultivation of Bamia 

 in Egypt is said to require more irrigation than the ordinary kinds. 



The yield of lint from Sea Island cotton is les-> than that from any 

 other kind grown in the United States, but on account of the length 

 and quality of the fibre it is adapted to uses to whic i the other kinds 

 are not suited, and its high market value compensates for the small 

 yield. 



According to Heuze % the time required for the maturity of a cotton 

 crop is divided as follows : from seeding to fl twering, New Orleans 80 

 to 90 days, Sea Island 100 to L 10 days ; from flowering to maturity, 

 New Orleans 7u to 80 days, and S^a Island about 80 days, making the 

 total period of growth about 5 to 6J months. According to the same 

 authority, the best average daily temperature for the growth of cotton 

 is from 60° to 68° F. for the period from germination to flowering, 

 and from 68° to 78° from flowering < o maturity. Dr. Wight § says 

 that for the proper maturity of the best qualities of American cotton 

 an increasing temperature during the period of greatest growth is re- 

 quired. The failure to produce in India a quality of fibre equal to 

 the American product from the same kind of seed is attributed to the 

 fact th it in the climate of the former there exists a diminishing rather 

 than an increasing average daily temperature. 



The effect of too much rain is to form too much plant and not 

 enough fruit, while serious drought causes a stunted growth of the 

 plan i in which few bolls are formed and these ripen prematurely. In 

 the latter case the resultant crop is generally short in staple aud poor 

 in quality. 



The structure of the cotton fibre has been studied to a considerable 

 extent, and the works of Bowman || and MonielT may be considered as 

 standard on this part of the subject. The first thing noticed in com- 

 paring samples of cotton is the difference in the length and the fine- 

 ness of the fi >re, and upon these factors almost entirely depends the 

 commercial grading of the crop. The principal species of cot ion vary 

 in respect to the length of their fibre within rather constant limits, 

 dependent upon soil, culture, and atmospheric conditions. The fol- 



* Floia of British India, 

 t Kew Report, 1887, p. 26. 

 % Plantes Iiidustrielle^, Vol. I, p. 13!). 

 § Journ. Agr. Hort. Soc. India, 7 (1849-50), p. 23. 

 || Structure of the Cotton Fibre, F. K. Bowman, Manchester, ls8l. 

 H The Cotton Fibre, its Structure, &c, Hugh Monie, Manchester and London, 

 1890. 



