16 HINDI COTTON IN EGYPT. 



to have a somewhat reddish spot at the base, especialh' if the condi- 

 tions are not favorable for rapid growth. The differences become 

 more obvious as the plants grow, until the flowering stage is reached, 

 but they may lessen or disappear at maturity. In adult Egj^ptian 

 plants the veins of the leaA^es often become reddish, while those of 

 adult Hindi plants may become pale," 



After the color contrasts have disappeared, the recognition of the 

 Hindi plants requires notice of other less obvious details of the leaves, 

 flowers, and bolls. Thus the leaves of the Hindi cotton have the 

 lobes broader, more abruptly narrowed toward the apex, and usually 

 produced into longer terminal points. In Hindi hybrids there are 

 often 5 to 7 lobes which are often somewhat folded or plicate, as in 

 the Eg3'ptian cotton, the true Hindi plants having the leaves nearly 

 flat. The rounded basal lobes of the leaf are broader in the Hindi 

 cotton, so that the leaf as a whole is more nearly square or oblong in 

 shape. The corresponding margins of the EgA'ptian leaA'es are Jikely 

 to conA'erge or slope backward toAvard the stem.'' 



The sinus or notch at the base of the leaf, where the petiole is 

 inserted, is usually much broader in the Hindi cotton, exposing the 

 upper surface of the end of the petiole. In the Egj^ptian leaA^es the 

 sinus is generally very narrow or completely closed by the contact 

 or overlapping of the margins of the lobes. The Avider separation of 

 the lobes of the Hindi cotton may be considered as a consequence of 

 the thickening of the A^eins and the enlarirement of the end of the 

 petiole 



FLORAL CHARACTERS OF HINDI COTTON. 



The involucre that incloses the bud of the cotton plant is composed 

 of three bracts, small leaf-like organs, each margined Avith a fringe 

 of narrow teeth. The bracts of the Hindi cotton are more broadly 

 rounded at the base and have longer and more numerous teeth than 

 those of the Eg3^ptian cotton. Comparison of the Hindi bracts 

 shoAvn in Plate III Avith the Egyptian bracts at the top of Plate IV 

 will enable these differences to be understood. Another diagnostic 

 feature of the Hindi bracts is that the teeth run doAvn nearer to the 

 base, a tendency that is shared by the Hindi hybrids. Three hybrid 

 bracts are shown at the bottom of Plate IV. The bracts of the 

 EgA^ptian cotton seemed to be someAvhat more cordate in Egypt than 

 in the United States, but the narrowh^ triangular form, straight 

 sides, and small teeth, remote from the base, generally render them 



« MutatiA'e ReA'ersions in Cotton, Circular No. 53, Bureau of Plant Industry, 

 U, S. Dept. of Agriculture, March, 1910, pp. 10-11. 



* For natural-size illustrations of leaves of Egyptian and Hindi cotton, see 

 Circular No. 42. Bureau of Plant Industry, December, 1909, pp. 4 and 5. 

 210 



