186 STUDIES IN INDIAN SUGARCANE SEEDLIXaS 



LEAF WIDTH AND TOTAL WEIGHT OF SEEDLING. 



Correlation 8. 



The total weight of the seedling, one of the factors by which the vigour 

 of growth may be judged, is taken only of those parts wliich are above ground, 

 — all the canes and shoots at crop time. To get this figure requires a certain 

 amount of management. In petty analyses canes are cut and they and their 

 leaves are lost, while at harvest certain of the canes are not infrecjuently dried 

 u]) or injured, introducing elements of doubt. Allowances have been made 

 with regard to these facts. Evei\ after this has been done, one would be 

 prepared for the absence of definite results. But a study of the table will show 

 that these doubts are unfounded, and there seems to be a very definite 

 positive correlation between the width of the leaf and the total weight at 

 harvest. This is perhaps what would have been expected, but it must be 

 remembered that the narrow leafed North Indian canes have vastly greater 

 tillering power than the thicker tropical ones, and consequently many 

 more canes in th(i clump. We shall see how this factor comes out in 

 the next table. In Naanal and the Shal'nrchynia cross theie is a rather 

 curious deviation, in that the first and last classes are the heaviest and the 

 two middle ones considerably lighter, a fact which would not have been 

 considered worthy of note, but for the unexpected agreement in the two sets 

 of figures. The Vellai cross agrees with the general collection series 

 and the positive correlation is very distinct. 



