ON THE SELECTION OF RAPE SEED. 



465 



For each sort seeds of medium specific gravity are generally 

 richer in oil , and we see from the above that the seeds whose 

 specific gravity lies between 1.105 and 1.085, '^^'^ richest in oil, and 

 these are followed by those of the specific gravity of i. 065-1. 045 ; 

 but that the seeds whose specific gravity is greater than 1.105 or 

 less than 1.025 are poorer in oil. It has also been observed that 

 the group richest in oil cansists as a rule of large and plump grains 

 of regular size. The results obtained in some exjDeriments made at 

 the Central Experiment Station at Nishigahara near Tokyo agree 

 tolerably well with mine and may be quoted for comparison : — 



CHOSEN. 



Air-dry. 



Water. 



Fat. 



HAMBURG. 



Air-dry, 



Water. 



Fat. 



.Seed which floated on the 

 distilled water of 30'^C. 



Seed which floated on the well 

 water of I5°C. 



Seed which floated on the salt 

 water of sp. gr. 1.05 



Seed which floated on tlie salt 

 water of sp. gr. i.io 



Seed which sunk in the salt 

 water of sp. gr. i.io 



10.63^ 



1 1.60 

 10.60 

 1 1.40 



33-40% 



43-25 



44.20 



43-99 

 37-95 



37-37"u 



4S.46 



50.00 



49.20 



42.S2 



1 1.80" 



II so 



11.80 



12 30 



31-50 

 40.35 

 40 90 

 41.20 

 36-35 



35-69% 



45-59 



46.01 



45-71 

 41.45 



According to Marck and Wollny large seeds contain generally 

 both absolutely and relatively more oil than small ones. The 

 results obtained by these investigators were follows : — 



MAREK. 



Beans. 

 Peas. 



j large seed. 

 ( small seed. 

 ( large seed. 

 { small seed. 



2.S9% oil in dry matter. 

 2.32 

 4.07 

 ■3-87 



