A DESERT GRAVEYARD 167 



scientists to attain the age of a thousand years I One of 

 these Giant Bisnaga has been growing in the University of 

 Arizona gardens for thirty-five years, is only about two feet 

 tall and eighteen inches through, even after the lapse of a 

 third of a century. It is in the highlands of San Luis Potosi 

 that we have discovered this giant, just as our long hot trek 

 is drawing to a close. We see that his trunk is single and 

 unbranched, cylindrical, and greenish or yellow-green. The 

 four straight sharp stout thorns are all brownish central 

 spines; no radials are present. The flowers are bright 

 yellow and showy, and the tops of the plants where they ap- 

 pear are covered with dense layers of long woolly cream- 

 yellow hairs. The large blossoms, two and one-half inches 

 long and as broad, come forth in early June, spreading wide 

 open in the forenoon and closing in late afternoon. 



Whipple's Visnagita (Echinocactus Whipplei) 



Northern Arizona, Northern Utah, Western Colorado, 

 and New Mexico 



But one more growth of this strange cactus land must 

 claim our attention ere the sun completes his journey across 

 the western skies and the goddess of Evening draws the 

 mantle of night over the land of the burning sun. It is a 

 Bisnaga native to the foothills and high mesas of northern 

 Arizona and Utah, western Colorado, and New Mexico, 

 but we cannot take the time on this trip to study In northern 

 parts. Science tells us that Whipple's Visnagita is one of 

 the smaller of the cactus clan and is generally to be seen 

 peering out from under other desert shrubs. Little is known 

 about this very interesting but tiny growth. It is far re- 

 moved from all of its near relatives In distribution, and Is to 

 be found as far north as Pleasant Valley near Great Salt Lake 

 in Utah. The ashy-white thorns are half an inch long or 



