118 ILLINOIS STATE ACADEMY OF SCIENCE 



For the seedlings from seeds of each size group, the three 

 highest average dry weights for roots, for shoots and for 

 plants, are in the seedlings from seeds of the three highest 

 densities. These average weights, however, do not vary 

 directly as the densities, for the highest value is sometimes 

 in seedlings from seeds of Density 3, sometimes in those 

 from seeds of Density 1 or 2. Plate II represents the aver- 

 age dry weights for the seedlings of each group. 



The maximum dry root weights for seedlings from the 

 small, the medium and the large seeds are in seedlings from 

 seeds of Densities 3, 1 and 2 respectively. The maximum 

 dry shoot weights, and also the maximum dry plant 

 weights are for seedlings from seeds of Density 1, for those 

 from the small and the medium seeds, and Density 2 for 

 those from large seeds. The minimum dry weights are, 

 as a rule, in seedlings from seeds of Densities 5 and 6. 



From these facts we may conclude: 



• (1) That, with the exception of the roots from the 

 medium seeds, the greatest fresh weights are in seedlings 

 from seeds of the three highest densities. 



(2) The greatest dry weights are also in seedlings 

 from seeds of the three highest densities. 



Comparison of Weights. — There is little correlation be- 

 tween the relation of dry to fresh weight and the specific 

 gravity of the seeds. It is apparent, however, that in the 

 seedlings from seeds of Density 3 the average percentage 

 which the dry weights of root, shoot and plant is of the 

 fresh weights of the corresponding members is as great, 

 sometimes greater, than that of any other density. 



The average percentage which the dry plant weight is of 

 the seed weight is always higher for the seedlings of seeds 

 of Density 6 than for those from seeds of Density 1 ; in 

 most cases it is also higher than for those from seed of 

 Density 3. This higher percentage shows that although 

 in size and weight the seedlings from the seeds of Density 6 

 are inferior to those of other densities, the seedlings from 

 seeds of Density 6 appear to make the best use of the re- 

 serve food in the seed. 



