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CHAPTER III. 



HOW A PLANT GETS OUT OF THE SEED. 

 By L. H. PAMMKI, 



The seed is the starting point of the individual in that great 

 class of plants known as the Flowering Plants, represented by 

 such common types as the pea, bean, corn, rose and cabb 



i LEAN. A common garden bean may be obtained at any time. 

 The seed is contained in a pod to which it is attached by a small 

 seed stalk. The seed is smooth, usually longer than b 

 There are many kinds of beans, the commonest beau is \ 

 some beans are bluish black, others are spotted wita b :ov, .1. o 

 are yellowish. You will observe that the seed lies o.i 6:ie side. 

 Some beans are flattened on the two ends because they were 

 packed so very closely in the pod that they touched each other. 



You will observe that the two sides are much, narrower . an the 

 middle. On one side is a pro:iii:i3.it spot callel the scar orhilum. 

 Fig. 3. This is where the seed stall, w is attached to the see,! On one 

 side of the scar you will notice a very small hole somev.hat sunken 



in the bean, the micropyle. On the other 

 end of the scar a pair of slightly elevat- 

 ed points. We will now soak the beans 

 in water for half an hour. They have 

 greatly changed in their outline. The 

 beans are no longer smooth and even as 

 they were when we first examined them. 

 They are very much wrinkled. This 

 wrinkled appearance is clue to the water which they have taken up. 

 We can now pull off the white covering or shell as it is com- 

 monly called. This white covering is known as the seed-coat or 

 testa. The purpose of this coat is to protect the more delicate 

 parts of the plant within. W'e shall look out for the little plant tucked 

 away on the inside. We will now examine some beans which have 

 been in water twelve hours. The beans are larger; they have taken 

 up much more water. The ridge near the small opening on one edge 

 of the seed scar is prominent. The seed coat should now be care- 

 fully removed. After the removal of the seed-coat two large 



Figure 3. 



Bean seed in process of germination. Testa or seed- 

 coat broken, showing the cotyledons,'"/. The hilum 

 or szar where the seed was attached shown at //. The 

 small opening in the testa, micropyle shown at '". At 

 the base of the radicle, the caulicle. 



Figure 3. 



Seed of bean, // hilum or 

 seed scar, >" micropyle. " two 

 processes arillate. 



