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small trees and shrubs, Mimosaceae predominating. One of 

 these small trees is a Clerodendron, or ally thereof, with very 

 showy flowers. Another tree is a beautiful new species of Hauya. 

 A new species of Linociera bore excellent edible fruit. The open 

 spaces were clothed with composites and shrubby heliotropes 

 and a graceful bamboo grows freely. Vitis bianco is a very 

 peculiar grape, with massive but inedible fruit. Upon the rich 

 shaded banks beautiful Achimenes intermingle with a plant 

 related to Tradescantia, its broad fleshy leaves lying flat upon the 

 ground and beautifully variegated with purple and several shades 

 of green. Here grew upon the rocks, in sunny places, a peculiar 

 Opuntia, unlike any that I have seen elsewhere, and about the 

 edges of cliffs were robust growths of Plumiera. Quite a collec- 

 tion of plants was obtained upon this mountain but I have found 

 no opportunity of studying them. 



Returning to Mexico City, and traveling thence via Puebla, 

 we pass down into the state of Oaxaca, a region which is really 

 a continuation of the Balsas district, though farther south and 

 correspondingly hotter. Its conditions of aridity are about the 

 same as those of Balsas. Like Balsas, too, it possesses a formid- 

 able mountain range. In the highlands about Puebla, we are 

 surprised to see the otherwise bare ground densely carpeted with 

 a bright rusty yellow Cuscuta. It probably lives upon grass 

 rhizomes. 



Approaching Oaxaca, we pass for many miles through one of 

 the greatest of mountain canyons, in some places approaching 

 in depth and grandeur our Grand Canyon of the Colorado. 

 Some of the summits in the vicinity of this canyon are said to 

 be almost inaccessible, while others can be scaled only on foot 

 and by a few circuitous routes. Several days were spent in this 

 canyon. My special work was laborious and exacting, but I 

 managed to snatch a collection of nearly a hundred species. These 

 and the very many that I saw without being able to collect them, 

 have left me with an intense desire to spend some time in that 

 region. The proper time to collect here is from late June to 

 September. In the bottoms of the canyons and along the sides 

 of the shaded ravines, where one can traverse them, he finds a 



