CALIFORNIA PLANTS IN THEIR HOMES 



special uses for the timber from very tall pine trees ? Think 

 whether the family of cone-bearers furnishes a considerable 

 part of wood used in building and manufacturing. You 

 will decide that, whatever rank the botanists may assign to 

 this family, it is certainly a very interesting and useful one. 



The other division of seed-bearing plants, the division 

 that produces seeds in ovaries, is divided into two great 

 classes. To illustrate the first class, collect all the follow- 

 ing that you can, remembering to get roots, leaves, flowers 

 and seeds when possible: lilies and plants resembling lilies, 

 such as Yucca, gladiolus, crocus, flag; different kinds of 

 grasses, including wild oats, wheat, barley and Indian 

 corn ; callas, cannas, cat-tails, rushes and tules. Perhaps 

 some one can furnish the flowers and young fruits of the 

 banana, palm and century plants ; many of you can at least 

 watch these last three plants out of doors. 



The seeds of plants of this group are usually difficult to 

 examine, but they all, like the corn and onion seeds, have 

 only one seed-leaf or cotyledon, so the plants are called 

 monocotyledons. Cut thin slices across the stems of these 

 plants, and notice how the woody strands are arranged. 

 They are more compact near the outside, but there 

 are some scattered strands all through the softer central 

 tissue, or pith, as it is called. Stems that have the woody 

 strands arranged in this way are called endogenous, and so 

 plants of this group are endogens. This is not the most 

 economical way to arrange the wood ; the very best way is 

 for stems to have all of these woody strands form a cylinder 

 about the pith. Most grasses omit the pith entirely except 

 at the joints, and so a wheat straw can support many times 

 its own weight, and can bend with the winds without 

 breaking. 



Now notice the leaves of this group of plants. Are 

 they usually simple or compound ? Are their edges notched 

 and cut, or entire ? Are the woody strands, or veins, paral- 



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