SUPPLEMENT 



polycarpa, known as rattlesnake weed, and described in Chapter XIV, 

 have some very weedy habits, although on the whole they are more 

 attractive than troublesome; they are supposed to provide a remedy 

 for rattlesnake bites. The Euphorbia that is by some believed to be 

 poisonous to gophers, is E. Lathyrus, Linn., an escape from cultiva- 

 tion. The skunkweed is Gilia squarrosa, H. & A., more common 

 northward; Portulaca oleracea, the purslane, so troublesome in our 

 Eastern States, is only occasional in California, although it seeks to 

 adapt itself to the dry season by reducing its fleshy leaves to cylinders. 

 Many of our most familiar weeds belong to the nearly related families, 

 Polygonaceae, Amarantacese, and Chenopodiaceae. The most com- 

 mon species of Chenopodium are foreigners, and are known as pig- 

 weed or goosefoot ; the one in the illustration is C. Album, Linn. 

 Atriplex is another genus of Chenopodiaceae, and A.bracteosa, Wats., 

 is a common tumble-weed along Los Angeles streets. The very com- 

 mon tumble-weeds of cultivated lands however, are species of Ama- 

 ranthus ; they are too familiar to need description. Tumble-weeds are 

 generally supposed to scatter their seeds as they are rolled about by 

 the wind, but in this section the seeds fall before the plants begin to 

 roll; and, like most of this group, they may well trust the dispersal 

 of their minute and very numerous seeds to the wind. The doves eat 

 great quantities of these seeds, and may aid in distributing them. 

 Rumex, the dock, and Polygonum the knotweed, are genera belong- 

 ing to the same family as the Eriogonum ; fragments of these plants 

 are illustrated in the Reader. The Polygonum aviculare, Linn., of 

 the picture, spreads out in flat circular mats two or three feet in 

 diameter, attaining in summer, on our hard, baked adobe soil, a much 

 greater size than in the Eastern States. Its slender, woody stems are 

 green, and must perform much of the vegetative work ; it is said that 

 cattle will eat it when hard pressed. All these plants have small and 

 inconspicuous flowers, and at first glance one would pronounce them 

 self pollinated, as most of them doubtless are ; but the flowers are 

 exceedingly numerous, and the wind probably aids considerably in 

 their pollination ; in fact, on closer examination, one finds that several 

 species are quite incapable of self pollination, either because they are 

 unisexual or because they mature their stamens only after their own 

 stigmas are past the receptive stage. As stated in Chapter III, it is 

 not easy to explain fully the success of these ubiquitous weeds, which 

 thrive in the most unpromising places. They seem to have inherited 

 virility from their ancestors, which, for centuries, and in many 

 countries, have been conquering weeds. 

 There are in Southern California several really ornamental plants 



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