298 Haeris M. Benedict 



TABLE 4. Effect of Light and Shade on Size of Vein Islets. Vine 53 



Leaves gro^ang in shade 

 (number of leaf) 



1 



Area of 



islets 



(square 



millimeters) 



Leaves 

 growing in 



light 

 (number of 



leaf) 



Area of 



islets 



(square 



millimeters) 



1 . . 



0.1511 

 0.1376 

 0.1654 

 0.1543 

 0.1517 

 0.1431 

 0.1571 

 0.1635 

 0.1569 

 0.1607 



1 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 10 



1543 



2 



1678 



3 



1751 



4 ; 



1642 



5 



1657 



6 . 



1635 



7 



. 1706 



8 



1613 



9 : 



1534 



10 



1642 







Average. . ... 



0.1541 





1640 









Uniformity in size of vein islets in each vine 



Schuster and von Zalenski both treated the length of veinlets as a rela- 

 tively constant character for each plant and even for each species. Most 

 of their work was done with herbaceous annuals, or with a relatively few 

 garden shrubs or trees which may well have been of nearly uniform age. 

 Unless all the leaves of an individual plant show vein islets of relatively 

 equal size, this character cannot be used as a criterion of the age of the 

 vine. In table 5 are shown conditions regarding uniformity of Vitis 

 vulpina. The average in each case is of ten or more leaves from each vine. 



TABLE 5. Uniformity in Size of Vein Islets in Each Vine 



Number of vine 



Minimum 

 area of islets 



(square 

 millimeters) 



Average area 



(square 

 millimeters) 



Maximum 



area 



(square 



millimeters) 



1 



0.1843 

 0.3581 

 0.5001 

 0.2598 



0.2039 

 0.3684 

 0.5188 

 0.2700 



0.2175 



2 



0.3980 



3 



0.5288 



4 



0.2958 



