132 STUDIES IN INDIAN COTTONS 



of the petal appears to correspond to the wliite condition as illus- 

 trated in the above two cases (2 & 3). This is illustrated by Table 

 XV. From this it would appear that the pale yellow factor is also 

 present in Type 3 which will be represented by the formula RRYYPP, 

 Type 10 having the constitution rryyPP. That this does not truly 

 represent the constitution of Type 3, appears to be indicated by a 

 cross between Type 3 and Type 9. Assuming Type 9 to have a 

 form rryypp we should expect this cross to produce plants with 

 pale yellow petals. This, however, does not occur. For the present 

 the true constitution of the pale yellow form Type 10 nuist remain 

 in doubt until the examination of the cross between this type and a 

 white flowered form has been completed. 



D.—The Leaf Factor. 

 This character has been described in detail on a former occa- 

 sion (22). Opportunity for further investigation has been lacking 

 and the results there recorded need not be reconsidered in this 

 paper. 



E. — Tlie Type of branching and the length of Vegetative 'period. 

 The inter-dependence between the type of branching and the 

 length of vegetative period is a matter of the utmost practical im- 

 portance. It is essential that a plant which is to be cultivated on 

 a field scale in the United Provinces should pass through the entire 

 stages and produce an abundance of fruit between the time of 

 sowing in May or, in the case of unirrigated lands, at the l)eginning 

 of the monsoon and the end of the year. Under these conditions, 

 if a renmnerative yield per acre is to be obtained, the plant must 

 commence to ripen its fruit by the middle of October at latest. This 

 means that flowering should commence in the end of August, giving 

 a maximum vegetative period, i.e., the period between the date of 

 sowing and the appearance of the first flowers — of 80 to 90 days — 

 a period which imist be considerably reduced in the case of a crop 

 grown on harani lands. Table XVI shows that in the monopodial 

 types vegetative period is considerably longer than that of the 

 sympodial types, and too long to render the cultivation of such forms 

 on a field scale practicable. In crosses, therefore, which are pro- 



