272 Principles of Plant Culture. 



Germination (28). Give an exercise in testing seeds 

 with the apparatus shown in Pig. 6. 



■'"~Moisture essential to germination (29). Soak one lot of 

 navy beans in water until they are fully swollen, and 

 another lot until they are about half swollen. Wipe the 

 beans as dry as possible, put each lot into a bottle, cork 

 the bottles, and set them in a warm room. The fully- 

 swollen beans will usually germinate promptly, while 

 the others will not. 



Oxygen essential to germination (jil). Perform the saucer 

 experiment as described. 



Also place seeds of rice in two bottles, and add to each, 

 water that has been boiled 20 minutes; cover the water 

 in one bottle with a little olive- or cotton-seed oil. It is 

 important to soak the seeds a short time in boiled water 

 before putting them in the bottles to remove the air in 

 K^ontact with their seed-cases. 



Germination hastened by soaking seeds (36). Soak seeds 

 of Indian corn two or three hours in warm water, and 

 let each student place in a seed tester a sample of the 

 soaked seeds, with one or two other seeds of the same 

 kind that have not been soaked. 



Germination hastened by mutilating the seed-case (37). 

 This may be illustrated with seeds of the navy bean, in 

 the seed tester. 



The plantlet (41). Place seeds of radish, onions etc., 

 loosely on the surface of a saucer filled with fine moist 

 loam; keep the surface moist and note the repeated at- 

 ^mpts of the hypocotyl to enter the soil. 



Seeds of the pumplcin family should be planted flatwise (43). 

 Plant seeds of the pumpkin or squash, in the three posi- 

 tions indicated, in large greenhouse saucers. Cover each 

 saucer with a pane of glass and place all in a warm room 

 until the plantlets appear, after Avhich note the number 

 of each lot of seeds of which cotyledons appear above 

 the surface. 



Development of plantlets (45-47). Devote several exer- 

 cises to a study of the development of plantlets of the 

 bean, pea, wheat, Indian corn, pumpkin, etc. To fur- 

 nish the plantlets, seeds of the different sorts should be 



