Germination. 23 



we shall find that the first lot will swell fastest, the second 

 next and the third slowest. Few seeds will absorb enough 

 water from damp air at ordinary temperatures to swell 

 much. 



b The~ points of contact. If we weigh, two lots of 

 100 beans each, on a delicate balance, and mix each lot 

 with well-crumbled, moist loam in a fruit jar, packing 

 the loam tightly in one of the jars and leaving it as 

 loose as possible in the other, close both jars to prevent 

 evaporation, and after twenty-four hours sift the beans 

 out of the loam and weigh the two lots again we shall 

 find that the beans in the jar containing the compacted 

 loam have increased more in weight than the others. 

 This indicates that the beans in this jar have absorbed 

 water faster than those in the other, because they were 

 in contact with the moist loam at more points. 



c Temperature. If we fill two bottles with beans, 

 adding ice water to one, placing it in a refrigerator, and 

 lukewarm water to the other, setting it in a warm room, 

 we shall find that the beans in the latter bottle will swell 

 more rapidly than those in the former. This shows that 

 a warm temperature favors the absorption of water a 

 fact that is true of all seeds. The same would have been 

 true had we planted the beans in two samples of moist 

 earth, placing these in different temperatures. 



d The nature of the seed-case.* In the bean, Indian 



* The term seed-case is here used to designate the outer covering of the 

 seed as the word seed is understood by the seedsman or planter. Every 

 seed, as we buy it in the market, or when ready for planting, has one or 

 more covering layers. In the peanut, for example, what we here call the 

 seed-case is commonly called the shuck; in the cocoanut it is called the 

 shell; in the bean and Indian corn it is more often called the skin. In 

 botany, the outer coverings of seeds are given different names, as peri- 



