42 HATCH EXPERIMENT STATION. [Jan. 



which seeds exhibit, the more important it is that a larger 

 number should be employed in order to obtain true aver- 

 ao'es. Where seed showed 95 per cent, germinating ca- 

 pacit}^, a test including one hundred seeds is of some value. 

 On the other hand, where there is only a germination equal 

 to 10 per cent., a truer average can be obtained by employ- 

 insr eiofht hundred or a thousand or more, or, what is better, 

 to repeat the experiment at least half a dozen times with a 

 smaller number of seeds. The high percentages given are 

 somewhat misleading, as the number of seeds used was not 

 sufficient to obtain reliable averages. All of the experi- 

 ments could be repeated to advantage. Since in many 

 instances the seeds were used up, it was not possible to 

 continue the experiments further. These experiments, 

 nevertheless, possess a certain value, and the results coin- 

 cide in a general way with what we have continually ob- 

 served in the greenhouse. In germinating thousands of 

 lettuce seeds in boxes we have noticed many instances sim- 

 ilar to that shown on No. 21, although the percentage of 

 gain is too high for average results. The average accelera- 

 tion given in all of the experiments shown in the table, or 

 the percentage of germination noted on the fourth day after 

 planting, was 25 per cent, in favor of the sterilized soil. It 

 will be noticed that the tomato seeds do not respond to ster- 

 ilized soil, and in four out of seven tests those growing on 

 unsterilized soil gave the best results. Since these experi- 

 ments are preliminary ones, and are being continued, further 

 comments at this time are not necessary, except to relate 

 that from an economic point of view we consider it worth 

 while to start such plants as lettuce, cucumbers, melons, 

 tobacco, etc., in sterilized soil, provided steam is available. 

 In such cases the expense would be very insignificant. Be- 

 sides returns from acceleration and increase in germinating 

 capacity, the important factor of immunity from diseases 

 such as those arising from the damping fungus, etc., is 

 important. 



