596 Home Nature-Study Course, 



6. What do you find between each layer? 



7. Carefully cut open the bulb and observe the central part. 

 Describe what you see. 



Facts for teachers. — Onions differ in shape from almost a perfect globe to a 

 long, slim bulb or a much tiattened one; in color thcj- are white, yellow or red. 

 The roots, which grow in a thick tassel at the base of the bulb, are white and 

 thread-like, but in good soil may grow several inches long, each one probing deep 

 for plant-food and moisture. Each layer of the bulb is veined lengthwise and 

 every vein extends upward into the leaves, showing that the bulb is onh^ a modi- 

 fication of the leaves above it, swollen with the food stored there for the preser- 

 vation of the plant. The covering on each layer may be stripped away, the inner 

 one most easily, which is like a filmy bit of silk. Then with even a cheap lens 

 it is easy to see the storage cells; filled mostly with starch, sugar and water. In 

 the center will be found the shoot, which, when the bulb is planted will pro- 

 duce flowers and seed, unless it is a " multiplier " when it will contain several 

 little pips each one of which will form a new bulb. 



LESSON LV. 



LEAF AND FLOWER. 



Purpose. — To awaken an interest in the structure of the plant, and 

 the uses of the different parts. 



Material. — A leaf and flower in the hands of each pupil. In the 

 hands of the teacher an entire plant, with bulb, scape and globose umbel 

 of flowers. 



Obscri'atioiis by pupils. — 



1. From what part of the plant does the scape or flower stem 

 spring ? 



2. What is the shape of the scape? Is its color the same as the 

 leaves? Is it solid or hollow? Is it taller or shorter than the leaves? 

 Does it bend readily or is it stiffened with woody fibres? 



3. \Miat is the color of the flower? 



4. How is the flower attached ,to the scape ? 



5. How many parts has the perianth or outer part of the flower? 



6. Count the stamens and observe where they are fastened to the 

 flower. Do they hold their little pollen-boxes inward toward the pistil 

 or toward the flower-cup? 



7. Does the flower smell as strong as the rest of the plant? 



8. Do you think the tiny flowers resemble their relatives, the lilies, 

 in any way? 



9. Describe the onion leaf ; does it grow from the center or outer 

 part of the plant? Is it .solid or hollow? Is it netted or paralleled 

 veined ? 



10. Docs each leaf help to form a layer of the bulb? 



Facts for teachers. — The scape or flower-stem nf the onion springs from the 

 center of the bull). Tt is round, hollow and swollen a little above the base, then 



