52 THE COTTON PLANT IN EGYPT CHAP. 



months' clear warning as to whether his crop will be late 

 or early. Specific differences between various strains of 

 cotton depend in the first instance on the method of 

 branching. If the first branches of the young plant are 

 sympodial flowering shoots, the flowering will probably 

 be early. Sometimes, however, strains have been noticed 

 which ought to have been early but were actually late, 

 owing to a propensity for shedding the unopened flower 

 buds. Again, specific differences due to branching may 

 take the form of irregularity ; all the plants of some strains 

 in the author's possession (notably King Upland), come into 

 flower almost simultaneously, even if some are stunted ; 

 other strains show a wide scatter among plants which 

 appear to be equally healthy. Other, and more subtle, 

 differences can only be relegated to the protoplasm itself 

 for ultimate explanation, some strains developing identical 

 flowering branches at a much slower rate than their 

 neighbours, just as the lateral roots grow more slowly than 

 the tap-root under the same environmental conditions. 



A point of importance, which is still obscure, relates to 

 the influence of the environment upon the nature of the 

 branch arising from a bud. In certain circumstances, 

 not yet clearly understood, but apparently including 

 excessively high night-temperatures, the plant delays its 

 formation of flowering branches. In many cases the delay 

 is only apparent, the flower-buds being formed but soon 

 shed. In others it is real ; " Nyam-nyam Kidney " 

 cotton grown at Giza, though otherwise healthy and 

 growing strongly, forms very few flowering branches. 



When dealing with most pure strains we find consider- 

 able uniformity in the date of the first flower. The 

 stunted plants, if any, flower late, so that a close corre- 

 lation here exists between the height of the young stem 

 and the flowering-date. Curiously enough, however, this 

 correlation vanishes when we reach the normal plants, 

 which all flower at about the same time in spite of notice- 

 able fluctuations in height. 



