79 



though the very large and conspicuous ones are confined to 

 certain districts. Agaves are mostly confined to the mountains 

 or rocky places. Of all these plants, the most striking is a 

 giant branching yucca, reaching a height of twenty feet or more, 

 which bears its dense panicles of white flowers, more than a yard 

 in length and two thirds as broad, in a strictly pendulous position. 

 The larger shrubby growth is mostly mimosaceous, consisting 

 of Prosopis and Acacia, with smaller mimosas and calliandras 

 about their bases. 



Very frequently the Prosopis attains the dimensions of a 

 good-sized tree, though this more commonly occurs as we are 

 entering the fertile or semi-fertile southern districts. It is very 

 rare that we encounter streams in this region, though arroyos, 

 carrying water in the rainy season, are seen in all directions. In 

 such locations, where there is a water supply not too far below 

 the surface, a fringe of cottonwoods and pepper trees may be 

 seen. 



The herbaceous patches of bloom, to which reference has been 

 made, consist chiefly of Compositae, especially Pedis, Actinella, 

 Layia, Melampodium, and taller Baileya, Coreopsis, Grindelia 

 and Gymnolomia. There are also many tuberous rooted ipomeas 

 and oxalids. 



Everywhere in sight are mountains of enormous height, many 

 of their slopes being apparently inaccessible. Their appearance, 

 for the most part, is even more arid than that of the plains, 

 but since they receive much more frequent and copious showers, 

 their upper portions probably possess a rich and interesting flora. 

 It has never been my lot to ascend any of them. 



The northwestern desert region I have never visited, and I 

 must say the same of the eastern coast, so that I shall not at- 

 tempt a description of those regions. 



The transition from this desert table land, where the produc- 

 tion of cultivated crops without irrigation is impossible and 

 where water for irrigation is not to be had, by any present 

 methods, is of great interest. It must be stated, however, 

 that in some places portions of the desert have been brought 

 under cultivation by means of a water supply obtained either 



