CALIFORNIA PLANTS IN THEIR HOMES 



cotyledon, which is wrapped about the rest of the embryo, 

 and it is a cotyledon of many uses. It protects the embryo, 

 carries it out of the shell, plants it in the soil, carries it food 

 from the seed's storehouse, and in the meantime becomes a 

 good foliage leaf itself. Palm seeds, too, have single coty- 

 ledons which plant their embryos so deep that they are in 

 little danger from drought. One palm has huge seeds 

 weighing fifteen pounds or more; the cotyledon carries the 

 embryo down a foot and a half in the soil, and feeds it there 

 nearly a year before leaving it to care for itself. 



As the rains come, keep watch for seedlings that may 

 spring up along the wayside or in fields, vacant lots or 

 gardens. See if they first appear as arches, and if you can 

 find the seed-leaves. As the plumules unfold, see how 

 many of the plants you can recognize. 



We have seen how seeds are prepared to begin life by 

 the parent plants ; let us think of what. the seedlings do for 

 themselves. While the little plant is yet entirely within 

 the seed-coat, it drinks in water from the outside world, 

 and the water dissolves this stored food, and helps to 

 change some of it so that it can be used for growth. As 

 soon as the first white shoot pushes out, it begins to fit 

 itself to supply water. Watch some kernels of corn germi- 

 nate on moist blotting-paper. The tip of the root is hard 

 and smooth, but back of the tip, the root is covered with 

 dense fuzz, and every hair of this fuzz is a thin-walled cell 

 that eagerly drinks in all the water it can get from the moist 

 air. Roots that grow in the soil have root-hairs too, but 

 the soil clings to them and hides them. They are not 

 usually so long as those you see on the corn, but they are 

 sometimes so dense that the head of a common pin can 

 cover a hundred or more. 



Now, as a root grows, it does not lengthen everywhere 

 as you do. If you will mark a corn root with ink, as in the 

 picture, you will see that only the part just back of the tip 



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