1921.] Influence of Size of Seed on Yield of Potvj-oes. 45 



weight of seed is taken into consideration with the yield, then 

 the crop from the 2 oz. set is the heaviest of all. (2) That the 

 crop from the sets with secondary growth is very much gi'eater 

 than any of the others, which is a fact of considerable interest. 

 It is hoped that experiments will be continued to ascertain 

 whether such tuber sets, cut into pieces of 2 oz. weight, would 

 yield equally good crops. If such is the case, as is very probable, 

 then there would be great advantage in using such, especially 

 in view of the fact, as we shall see later, that the tendency to 

 secondary growth is in no way conveyed by the tuber. 



That the sets with secondary growths should have proved 

 such successful seed is, however, not surprising ; a secondary 

 outgrowth indicates a high vegetative activity on the part of the 

 parent tuber, and the outgrowth itself is in the nature of an 

 immature tuber, which experience has long shown to be the best 

 type of tuber seed. 



Samples taken at random from the crops derived from the 

 eight classes were analysed into the following groups of tubers : — 



Class a. — Tubers under 1 oz. in wei^lit. 

 ,, h, — of 1-1? oz. 



„ c— „ l|-2-6 oz. 



„ d.- .V41 „ 



e.-- f) oz. and upwards. 



The results are set out in Table IT. 



TABLE XL 





Seed Class. 



Weight 

 of 



Percentage of Total iu eacli 

 Crop Class. 



Heavy 

 Ware 

 d. and e. 

 combined 







Sample. 



a. 



b. 



c. 



d. 



e. 







lb. 















1. 



Qnder 1 oz. 



32 



4-0 



50 



18-0 



37-0 



36-0 



73-0 



2. 



1-33 oz. 



30-5 



5-4 



9-7 



29-5 



19-6 



35-0 



54-6 



3. 



2 oz. 



29-25 



3-45 



2-55 



.30-7 



24-0 



39-2 



63-2 



4. 



2-66 oz. 



30 



5-8 



2-33 



23-3 



26 -(5 



41-7 



68-3 



~). 



4 oz. 



29-35 



9-4 



8-9 



37-5 



20-5 



23-9 



44-4 



(). 



5 33 oz. 



30 



5-0 



8-6 



28-3 



18-3 



40-0 



58-3 





5-4)6 oz. 



30-5 



4-92 



10-6 



36-0 



23-3 



24-5 



47-8 



s! 



6oz. with out- 



















growths 



36-5 



5-45 



8-2 



34-3 



24-5 



27-5 



52-0 





Average of 

 8 chisses 



31-0 



5-43 



7-22 



29-7 



24-2 



33-6 



57-8 



9. 



Mixed seed 



27 



4-55 



4-93 



25-6 



32-5 



32-5 



65-0 



The percentages of weights of each group in each sample varied 

 within relatively small limits from each other, or from the 

 control sample derived from mixed seed of the same variety. 



