CHAPTER III 



common name is more suitable than these names often are. In 

 Southern California only the variety, the form having small woody 

 leaves, is found in lower altitudes, but in the mountains, where there 

 is more moisture and leaves can afford to transpire more freely, the 

 type with the larger leaves prevail. The flowers are types of those 

 that humming birds love to frequent. They are vivid scarlet, and 

 other guests, excepting long-tongued moths, are excluded because the 

 honey is at the base of a long tube with a marked constriction a little 

 above the base. The birds can usually be seen visiting the flowers, 

 except, perhaps, during the hottest part of the day. As can be seen 

 from the picture, they strike the large, rough stigma first on entering 

 a flower ; they are pretty sure to pollinate it if they come from other 

 fl jwers, for the pollen coheres in considerable masses on account of 

 the cobweb-like threads among the grains and these masses are 

 almost sure to catch on the bird's bill or feathers. If the children 

 watch the flowers they may find that they do not altogether depend 

 upon their guests ; the little masses of pollen often swing down so 

 that a light breeze or passing object, sometimes their own fluffy seeds, 

 may land pollen against a stigma. Of course if the children are 

 studying plants for the first time this subject of pollination must be 

 deferred until later. Considering the main topic, the story of the 

 pollination of these two flowers is quite a side issue, but it is a beauti- 

 ful story and can be read directly from Nature's page. 



There are other plants of the dry season that have not such obvious 

 devices for maintaining the balance between transpiration and water 

 supply as the plants we have used for illustration. This is especially 

 true of some introduced weeds. We day attribute their survival to 

 the innate hardiness that has made them universal weeds, or we may 

 see some explanation in their long and often thickened roots, or 

 we may advance the theory that the cell sap contains substances that 

 lessen evaporation, but the fact remains that often, very often, we 

 cannot fully explain these matters. No really scientific person pro- 

 fesses to " know all about it," nor is he deeply chagrined when he 

 finds that one of his theories must be abandoned. It is very unfor- 

 tunate to give children the impression that all of Nature's secrets can 

 be discovered by a superficial glance. But this is no reason why open 

 secrets should not be noted and enjoyed. 



The reasons for the fall of the leaves of native California trees in 

 autumn are not easily explained. It can hardly be due to the cooling 

 of the soil, for at just this time the rains cause a general bursting into 

 leaf among small perennials, and even some large shrubs or small 

 trees, like the Ribes and the elder, respond at once to the new 



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