1911.] Summary of Agricultural Experiments. 143 



Correlation between the Number of Eyes in Seed Potatoes and the 

 Yield (Deutsche Landiv. Presse, February Sth, 191 1). — Tests carried 

 out with four varieties of potatoes at the Agricultural Station at Ope, 

 in Sweden, in 1908, appeared to show the existence of some definite 

 connection between the number of eyes in the "sets" and the yield. 



Further experiments were undertaken in 1909 and 1910 at three 

 Swedish Experiment Stations. As a rule the number of eyes can be 

 taken as proportional to the size of the tuber, but in these trials tubers 

 of the same size, but with different numbers of eyes, were chosen as 

 far as possible. It was again established that the number of eyes in 

 the sets has an influence on the yield, both the weight and number 

 of the tubers increasing with the number of eyes. The following were 

 some results obtained : — 







Yield from 10 sets. 



Variety. 



No. of eyes. 











Weight. 



No. of tubers. 







lb. 





White " Jemtland " 



4-0 



8 6 



I 5 6 





10'2 



138 



244 



"Mandel"...'.' 



3-6 



5"3 



127 







IO'I 



io-8 



270 





5-P * 





98 





9'5 





177 







Yield from 25 sets. 



Red " Jemtland " 



8-2 



21-4 



2S7 





12-6 



30 $ 



497 



It is suggested that the productivity of a variety can be raised by 

 making use of these results, since it was found that the characteristic 

 of a large number of eyes in the sets was transmitted, to the crop of 

 tubers obtained; e.g., the following relation between the number of 

 eyes in the sets and in the tubers yielded was obtained in 1909 : — 



Number of eyes 

 in sets. 



Number of eyes in potatoes harvested. 



Large tubers. 



Average. 



Small. 



64 

 12-4 



9'8 

 i3'o 



6-6 



9'9 



6-8 

 77 



Varieties of Cereals and Thick and Thin Seeding of Oats (Field 

 Expts. in Staffs and Salop and at Harper Adams Agric. Coll., Joint 

 Rept., 1910). — Sixteen varieties of wheat were tried in 1910 on a good 

 loam soil previously under seeds, which had been dressed with 8 tons of 

 farmyard manure in July, 1909. The yields exceeded those of any 

 previous year, and all the crops were harvested in good order. There 

 were no great differences between the yields of the English wheats, but 

 Browick Grey Chaff again gave the largest yield (54 bush, per acre), 

 and the most profitable return per acre for grain and straw. The next 

 in order were Regenerated Squarehead, Victor, and White Wheat, all 



