213 THE PLANT WORLD. 



The study of the Internal structure of the seed is very difficult 

 for young pupils. The teacher should have several well-soaked 

 seeds dissected to show the pupils, and plain drawings on the 

 board. Call attention to the hard brittle seed-coat. 



Notice the short, straight peg. The fleshy halves of the seed 

 are not cotyledons, but food for the young plant. This may be 

 very carefully removed, showing the white, leaf-like, delicate 

 cotyledons. The plumule is too small to be easily seen. 



Germination. 



Material. — In boxes of convenient size, containing garden soil 

 or, preferably, clean sand, plant six or eight seeds of the common 

 white bean, the pea, corn, squash, having first soaked the seeds 

 for twenty-four hours. Plant about a week before the study of 

 how the}' break through the soil is taken up. 



The successive steps in germination may best be followed by 

 allowing seeds to germinate behind glass. For this purpose, line 

 a Wellsbach chimney with a tube of blotting paper, setting the 

 end of the chimney in sand or soil in a flower pot or box, and 

 fill the chimney with moist saw-dust to keep the blotter close to 

 the glass. (If this device is not convenient, an ordinary tumbler 

 may be used. The shallowness of the tumbler, however, does not 

 permit of very extensive root development.) 



Have the children place five or six seeds of each kind men- 

 tioned above in water to soak over night. On the following day 

 the pupils will observe that all the seeds have swollen. Tins is 

 tJie first step in germination and the point should be made at this 

 time. 



Now place these seeds between the blotters and the glass so 

 that they may be seen, and placed so that the tip of the peg of 

 some of the seeds points vertically downward, of others upward, 

 and of still others horizontally. Be sure that the corn grain is 

 placed with the embryo side next the glass. Keep the seeds moist 

 but not immersed in water, and, if possible, put in a dark place to 

 develop. Lead the children to see that this would be best by 

 questioning them concerning the light conditions under which the 

 seed germinates naturally in soil. 



