PAPERS ON BIOLOGY AND AGRICULTURE 125 



drawn for temperature 2b may be applied to seedlings 

 from similar seeds grown at 20- and 30 'C respectively. 

 Because of the limited number of large seeds no data is 

 available save at 25 C. The discussion will be confined to 

 a consideration of average values. The data for seedlings 

 grown at 20 -C are found in *Tables 40 to 43, that for those 

 grown at 30 C in *Tables 44 to 47. 



a. Growth as Related to Specific Gravity. 



A study of the above tables shows that with but few ex- 

 ceptions the conclusions drawn for the relation of growth 

 to the specific gravity of the seed, for temperature 25 C are 

 also true for temperatures 20' and 30 -C. At 25 'C there 

 was no correlation evident between length of hjT30C0t\i 

 and specific gravity of seed; at 20-, however, the greatest 

 average length of hj-pocotyl in seedlings grown in soil ap- 

 pear in those of Densities 1, 2 and 3. 



At 25- C, the percentage of the dry plant weight to the 

 seed weight is higher for seedlings from seeds of Densitj' 

 6 than for those from seeds of Densities 1 and 2. At 20 'C, 

 this is true only for seedlings gro^^ii in water, and at 30 -C, 

 it applies solely to seedlings from medium seeds gi'own in 

 water. 



b. Growth as Related to Size of Seed. 



The seedlings grown at 30 -C show the same correlation 

 between growth and size of seed as is sho\^^l by those grown 

 at 25 -C. For the seedlings grown at 20 C, however, the 

 following points of difference seem evident : 



(1) The average heights and average weights of seed- 

 lings from small seeds are more nearly equal to the similar 

 average values of seedlings from medium seeds of like 

 densities, at 20-C than at 25-C. In a few cases the average 

 values for seedlings from small seeds exceed those for 

 seedlings from medium seeds. 



(2) From the total dry vreight it may be inferred that 

 at 20-C the seedlings from small seeds use their resen-e 

 material to better advantage than those from the medium 

 seeds. 



(3) At 20-C, the greater rate of growth is shown by 

 seedlings from the small seeds. 



