MAMMALS OF THE MEXICAN BOUNDARY. 65 



Arizona to the head of Black Canyon (between Antelope and Bumble 

 Bee) , and up the Verde River to Bloody Basin, between old forts 

 Verde and McDowell. It also occupies southern slopes of hills be- 

 tween San Carlos and Grlobe City, Arizona. On Tonto Creek its 

 range extends nearly to the Wild Rye. Large sahiiaras (40 feet 

 in height) were noted on Ash Creek, a tributary of the Gila, at 

 the foot of Black Canyon, in Graham County, Arizona. The sahuara 

 affords safe nesting places for many species of birds and a secure 

 retreat to several small mammals. It seldom grows upon the desert 

 plains, but appears as soon as the bordering foothills are approached, 

 extending up the slopes and canyons to the upper limit of the Lower 

 Sonoran zone. (Plate VlII, fig. 1.) On April 4, 1885, 1 passed, near 

 Rillito Station jn the Santa Cruz Valley, a ranch owned by an 

 Englishman who had planted Cereus giganteus to form a fence, which 

 would have been a great success had not he mistaken some Echino- 

 cactus wislizeni for the sahuara, the latter having outgrown the 

 bisnagas, leaving gaps in his fence. Respecting the season of flower- 

 ing, etc., I find the following data in my journal : 



May 5, 1885, when marching from Mountain Spring to Fort Lowell, 

 Arizona, I saw circles of opening buds on the summits of the sahuaras 

 for the first time. Four days later, on Picacho Peak, Arizona, the 

 sahuara^g were crowned with wreaths o'f white flowers. At Casa 

 Grande, May 10 — 



all of the sahuaras are now in bloom. * * * After turning the point of a 

 mountain between the Gila River and Phoenix, Arizona, we came to a forest 

 of the giant sahuara, which I noted as being of somewhat larger size and more 

 branched than those seen between here and Mountain Spring [near Tucson]. I 

 think one that I saw would measure between 40 and 50 feet in height, but this 

 may be an overestimate. One of its arms or joints would exceed the average 

 size of those growing about Bumble Bee or on New River — ^the northern and 

 upper limit of its range. 



Lieutenant Gaillard writes : 



Probably nowhere along the boundary does the cactus growth attain such 

 luxuriance as in the foothills of the Sonoyta Valley. The giant cactus here 

 attains a height of 40 or 50 feet and forms perfect forests, if the word forest 

 can properly be applied to a collection of these strange, ungainly, helpless- 

 looking objects, which seem at times to stretch out clumsy arms appealingly to 

 the traveler, and which one can not see on its native desert without uncon- 

 sciously associating it with the uncouth forms of vegetation peculiar to the 

 Carboniferous era. 



Maj. John G. Bourke gives the following: 



And the majestic " pitahaya," or candelabrum cactus, whose ruby fruit had 

 long since been raided upon and carried off by flocks of bright-winged humming- 

 birds, than which no fairer or more alert can be seen this side of Brazil. The 

 " pitahaya " attains a great height in the vicinity of Grant, Tucson, and Mac- 

 Dowell [Arizona], and one which we measured by its shadow was not far 

 from 55 to 60 feet above the ground, — On the Border, 2d ed., 1892, pp. 53-54. 

 30639— No. 56—07 m 5 



