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marshland. Around the margins of such pools, especially the 

 natural ones, there is frequently seen a broad band of pink or 

 purple Cosmos, sometimes a hundred yards or more in breadth 

 and presenting a solid mass of color. Similar patches of yellow 

 Helianthus, Coreopsis and related genera are abundant. 



These are the conspicuous features of the flora, as viewed by 

 one who is passing through it. When we dismount and walk 

 over these hills and through the valleys, our interest centers in 

 the wonderful variety of small annual and perennial herbs, both 

 as to species and larger groups, which crowd into every undis- 

 turbed spot. 



In the foothills of the mountains of this region, the botanist 

 becomes quite lost in the profusion of unfamiliar plants. The 

 acacias and Prosopids exist in undiminished abundance and, grow- 

 ing among them so thickly as to make travel difficult, are nu- 

 merous species of Terebinthus, or Bursera, spiny erythrinas 

 bearing long moniliform pods showing brilliant scarlet seeds 

 through their half-opened sutures, stinging jatrophas, intricately 

 thorny Rubiaceae and small silk-cotton trees, and all these 

 frequently bound together by twining Clematis, Passiflora, 

 Thomaea and leguminous vines. Many of the smaller shrubs 

 also are leguminous, among them the beautiful Brongniartia , 

 with silky-white herbage and lovely dark chocolate-colored 

 flowers. In some places the arborescent growth is almost wholly 

 of the Palo Amarillo rubber-tree, Euphorbiodendron fulvum. 

 Extremely varied are the lantanas, their flowers ranging in 

 color from pure white or white with a golden eye, through 

 various shades of pink and purple, even to brilliant orange or 

 vermilion. Almost equally abundant and varied are the species 

 of Stevia. Among the herbaceous vegetation, purple flowered 

 Oxalis exists in great variety, with many Geraniums, purple 

 flowered ruellias and Nyctaginaceae, and yellow Tribulus. Ferns 

 of the hardier kinds, such as rigid pellaeas and notholaenas, are 

 frequent, but not nearly so abundant as farther south. Where 

 the canyons open out into valleys leading to the plains, the 

 Cactaceae comprise the greatest bulk and the most interesting 

 feature of the flora. In places the entire surface over many 



