304 



Bulletin 312 



untreated seed after the same time showed an average of only 48 per cent. 

 In all other lots, both treated and untreated, the total percentages germi- 

 nated after 2 1 days are not much larger than after the first five days. 



As is seen in Table 3, many of the seeds that did not receive acid treat- 

 ment failed to germinate after 21 days between moist blotters. On 

 examination, a few of these non-germinated seeds were found to be dead, 

 being soft and somewhat decayed. Most of the non-germinated seeds, 

 however, were bright in color, and the seed coats were hard and firm. 

 Practically all of these bright-colored seeds were really alive, as ^was 



Fig. 81 — Red clover seed I-5-5. One hundred seeds of red clover treated with concen- 

 trated sulfuric acid for 60 minutes. Ninety-one per cent germinated after 5 days. 

 Nine " hard seeds " remain 



shown by the subsequent tests given them. In order to further test 

 these hard, bright-colored seeds, they were taken from between the moist 

 blotters and treated at once with concentrated sulfuric acid for 30 or 

 60 minutes, after which they were thoroughly washed and again placed 

 in the germinator between moist blotters. 



The number of seeds from each lot thus treated is shown in Table 4, 

 in the column " Number of seeds." Thus, from the lot in Table 3 marked 

 I-i-i, 72 seeds were taken for the further treatment shown in Table 4. 

 These 72 seeds, as indicated in Table 4, had received the " previous 

 treatment " of being soaked in water 2 hours and remaining between moist 

 blotters in the germinator for 21 days. After treatment with concen- 



