68 



THE VITALITY AND GERMINATION OF SEEDS. 



TAHLK XXVI. Vitality of seeds preserved in different kinds of packages. 



Subsequent experiments were made, using envelopes of different 

 qualities, as well as varying the treatment of the packages. Samples 

 of cabbage, lettuce, and onion seed were put up as follows: 



(a) The regular seedsmen's envelope, made of a heavy grade of 

 manila paper. 



(b) Envelopes made of a medium quality of waterproof paper. 



(c) Envelopes made of a thin parchment paper. 



(d) Envelopes made of the same quality of parchment paper as for 

 the preceding series, but paraffined previous to being filled with seed. 

 The packages were then sealed by redipping the open ends. 



(e) Envelopes of parchment paper, as for the two preceding series, 

 except that the envelopes were first filled with seed, sealed, and then 

 the entire package was dipped in paraffin at a temperature of from 

 55 to 60 C. 



Samples of all of these packages were then stored under trade con- 

 ditions and in dry rooms in Ann Arbor, Baton Rouge, and Mobile. 

 The exact conditions of storage in the different places were the same 

 as described on pages 49 and 50. 



The samples were put up on May 20, 1901. The period of storage 

 ended on November 26, having continued 190 days. Unfortunately, 

 no special precautions were taken to dry the seeds. They were simply 

 air-dried samples; hence they contained a quantity of moisture suffi- 

 ciently large to give rise to an increased relative humidity of the 

 confined air in the paraffined packages. This increased humidity was 



