CACTACE^ OF NORTHEASTERN AND CENTRAL MEX- 

 ICO, TOGETHER WITH A SYNOPSIS OF THE PRIN- 

 CIPAL MEXICAN GENERA. 



[With 15 plates.] 



By William Edwin Safford. 



Scarcely any group of plants in the whole vegetable kingdom is 

 more remarkable for its strange and varied forms, the beauty of its 

 flowers, and its wonderful adaptation to desert life, than the cactus 

 family. To many persons the word "cactus" suggests perhaps the 

 beautiful night-blooming cereus of our conservatories or the rosy- 

 flowered Epiphyllums and Phyllocacti. These plants, together with 

 (he drooping epiphytal Rhipsalis, call up visions of tropical lux- 

 uriance far different from those suggested by the stiff columnar torch, 

 thistles and thorny viznagas of the arid deserts and rocky slopes of 

 mountains. Many of the latter are figured in various government 

 reports of explorations, in which some of the most remarkable are 

 described at length, not only as striking features of the landscape, 

 but also as welcome sources of refreshment to the weary traveler, and 

 food and drink for his exhausted beasts of burden.* 



Humboldt has somewhere spoken of the influence of collections of 

 exotic plants upon minds susceptible to natural beauty, relating how 

 he himself was seized with a desire to travel in tropical countries on 

 seeing certain exotic trees in the botanical garden of Berlin. Among 

 special collections of plants usually seen in conservatories few inspire 

 greater interest than those composed of Cactaceae. In this countr}' 

 the most important collection is undoubtedly that of the Missouri 

 Botanical Garden, at St. Louis. Other interesting collections are 

 those of the Department of Agriculture, at Washington, and the 

 New York Botanical Garden, at Bronx Park. In these the plants are 

 grouped for convenience of study according to genera, subgenera, and 

 species, under the protection of glass roofs. Other collections, ar- 

 ranged more artistically and under more natural conditions, in the 



'^ See Coville, Frederick V., " Desert plants as a source of drinking water." 

 Smithsonian Report for 1903, pp. 499-505. 1904. 



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