Methods of Breedixg and Lmi'kovkxg the Potato Crop. 583 



tuber-unit can be easily and quickly weighed. A satisfactory scale 

 should weigh accurately to at least a half ounce. Weigh the product 

 of the remaining tuber-units, examine the tubers more carefully as to 

 their character and uniformity of size in the tuber-unit and select about 

 fifty of the best units. These fifty units should naturally be from those 

 marked as having good healthy vines in the first examination before 

 digging, unless all of the vines at that time were in fairly good condition. 



%> 

 <• 



Fig. 3. — Four-hill tuber-units of Early Beauty of Hebron potato grown side by side 

 from original tubers of about same size. On left, low yielding progeny; on right, 

 large yielding progeny but of irregular shape. 



In making these final selections, if some hills in a tuber-unit are missing 

 the comparative yield can be easily calculated. If one hill is missing 

 a comparative yield for four hills is obtained by increasing the weight 

 from the three hills by one-third. If two hills are missing a comparative 

 yield for four hills would be double that obtained from the two hills. 

 If more than two hills are missing discard the unit entirely. 



The product of the tuber-units selected should then be placed in paper 

 bags, the product of one tuber-unit only being placed in a bag. A good 



