CALIFORNIA PLANTS IN THEIR HOMES 



most important thing of all, its seed production, on a tiny 

 moth no longer than your finger nail. The Yucca keeps 

 its anthers quite away from its big stigma, and does not 

 even provide honey for the moth; but the white, fragrant 

 flowers are easily found at night. The moth herself does 

 not need food, but she knows that when her eggs hatch, 

 her little larvae will be very hungry indeed, and the only 

 food they can live on is the Yucca seed. But she seems to 

 know something much more wonderful than this, and that 

 is, that the Yucca will not produce seed unless the pollen 

 reaches the stigma. At any rate this is what she does : 

 Before she lays her eggs, she gathers a mass of pollen 

 bigger than her own head ; she next lays her eggs in the 

 ovary of a flower, and then immediately crams the pollen 

 down the concave stigma of this flower. So the big Yucca 

 can trust to the mother instinct of this tiny creature, for 

 while her babies eat part of the seeds, there are quite 

 enough left to keep up the supply of Yuccas. 



Another group of monocotyledons is made up of families 

 so different in appearance that you would never guess 

 their relationship. It contains, for instance, the largest of 

 all monocotyledons, the palms, and also the smallest of 

 flowering plants, the duckweed, a tiny water plant hardly 

 as large as a common pin. There are several other water 

 plants that belong to this group, flowering plants that 

 either float on the water or grow along the margin of ponds. 

 Perhaps the one you would know best is the cat- tail, or 

 bulrush. But the best known of this group is the call a, 

 which you have already studied. All these plants are 

 related because, like the calla, they have small simple 

 flowers, usually many of them crowded together. The 

 clusters differ almost as much as the plants. There may 

 be a smooth spike surrounded by a showy involucre like 

 the calla, or a brown, velvety one like the cat-tail, or a much 

 branched but compact cluster, as in the palms, or one so 



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