6l2 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Table VI. — Result of Potato Experiments in 1913. 



Lot 



Variety 



Number 

 of tubers 

 examined 



Streak 



Blotch 



Phyto- 

 phthora 



Remarks 



A 



C 



B 

 D 



' Duke of York,' 

 originally from 

 Scotland 



98 

 71 

 115 

 89 



OOOO 



OOOO 



20 

 3 



42 

 4 



i doubtful mark. 

 (4 large tubers hollow, 

 1 1 doubtful mark. 



1 doubtful mark. 



E 

 F 



j ' Duke of York,' 

 L originally from 

 j Messrs. Sutton 



66 

 75 



O 

 O 



0 

 0 



I 



3 



1 doubtful mark. 



G 



H 

 I 



J 



L 

 K 



'Duke of York' 

 diseased sets . 



' Sutton Flourball ' 

 'Langworthy' (Liver- 

 pool 

 ' Langworthv ' 

 ' Up-to-Date ' . . 

 ' Northern Star ' . 



36 



70 



68 

 166 

 ? 

 ? 



O O OOOO 



O O OOOO 



0 



0 

 12 



? 

 ? 



129 tubers were exa- 

 mined, including small 

 ones. 



N.B. — Only the results from potatos of medium size are recorded here. 

 A large number of very small tubers examined were not diseased. 



The Table shows that blotch and streak were entirely absent in 1913, 

 even among the produce jrom sets affected with streak. The disease in 

 the potatos was this season entirely due to Phytophthora injestans, 

 and, curiously enough, practically confined to the produce from lots 

 A and B. 



Table VII. — Tubers from Plants produced by Diseased Sets scheduled 



with regard to Size. 



Number of 

 plant 



Total 

 number of 

 tubers 



Large 



1 



Medium 

 1 size 



Very small 





I 



5 



O 



2 



3 





2 



3 



O 



O 



3 





3 



11 



O 



4 



7 





4 



10 



O 



4 



6 





5 



5 



0 



3 



2 





6 



2 



O 



0 



2 





7 



9 



O 



5 



4 





8 



8 



O 



3 



5 





9 



3 



O 



0 



3 





10 



4 



O 



0 



4 





1 1 



5 



O 



2 



3 





12 



4 



O 



0 



4 





13 



9 



O 



2 



7 







8 



O 



2 



6 





w 



9 



O 



3 



6 





16 



4 



O 



0 



4 





17 



5 



O 



0 



5 





18 



3 



O 



0 



3 





19 



2 



O 



0 



2 





20 



9 



O 



3 



6 





21 



11 



O 



4 



7 







129 



O 



37 



92 





