50 CROSS-FERTILISATION IN' TIIK INDIAN COTTONS. 



" generation, as well as more rarely in the first, there is a marked 

 " reversion to G. neglecfiim ; while a reversion to a pure 

 " wight iainnn happens less frequently. 



' ' Here it happens that in the large plantations of India there 

 " exist intermediate forms which have made the English botanists, 

 " who consider these hybrid forms simply as varieties of one 

 " species, believe that between G. arhoremn Linn, and G. herbaceum 

 •' there are so many hnks that they must constitute a single 

 " species. 



" The species cultivated in the Old World have no agricultural 

 ' importance ; their capsules are always small, the wool is short and 

 " rather coarse compared with that of the American kinds, and 

 " cultivation has hitherto been unable to increase the dimensions of 

 " their capsules, or to improve the cotton." 



The occurrence of cross-fertiUsation of cotton outside India has 

 also been frequently noted. In America the belief in its occurrence 

 though of limited extent, appears to be very general. 



The opinions of several w'orkers in Anierica are recorded by 

 Middletou.* Webberf states that " In several instances varieties 

 " have been grown in single rows with other varieties all round 

 " them of such a kind that crossing, where it occurred, could be 

 " easily detected in the progeny. Plants growai from seed matured 

 " under such circumstances show but few crosses, indicating 

 " that the majority must have been self-fertilised. Judging from 

 " the observations thus far made, it would seem that ordinarily 

 " only 5-10 per cent, of the seeds are normally cross fecundated." 



The same author has also dealt with the effects of the occurrence 

 of such cross-fertilisation in its bearing on the methods of selection. J 



The work of Cook has already been referred to (p. 11). His 

 observations on certain Eg}'jitian cottons grown in America point 

 to the hybrid nature of some of the plants.§ 



• Loc. clt., p. 2». 



t U. S Dept. of Agr. Year-book, iy02, p. 370. 



t C. 8. Dept. of Agr. Year-book. 1898, p. 304 et 8eq. 



§ D. S. Dept. of Agr.. Bur. of Plant liul.. Bull. I5G, p. 2U. 



