GEOLOGY AND NATURAL HISTORY OP LOWER CALIFORNIA. 989 



rite, which seems to form the main mass of the hills, though in the dry 

 stream bed are abundant bowlders of granite, diabase, and more rarely 

 liparite and andesite. 



The next morning- it was found that our animals, which had been 

 merely hobbled in order that they might browse on the mesquite, had 

 strayed so far that it was nearly 11 o'clock before we were once more 

 in the saddle. In the meantime, while engaged in jjursuit of the ani- 

 mals, the camera was more than once brought into requisition, some of 

 the results being here reproduced in Plates 6 and 7. The giant cactus, 

 Cereus pringJel^ Plate C, is about 25 feet in height by 20 inches in diam- 

 eter at the butt. 



Larger forois, jterhaps 35 to 40 feet in height, occur, but this was 

 selected for photographing simply on account of its accessibility and 

 from its being in fruit, as shown in the knob-like excrescences near the 

 top. This fruit consists of a beautitul dark carmine pulp, with black 

 seeds, inclosed in an envelope or rind so beset with small needle-like 

 thorns that he who plucks needs fingers of brass. The appearance of 

 this pulp in that dry, hot region was tempting in the extreme, but the 

 realization disappointing, it being almost tasteless, and even failing to 

 quench the thirst. These awkward forms, resembling nothing more 

 than clustered mill logs standing on end, were quite abundant, though 

 widely scattered. Some were straight and limbless as saw logs; others 

 gave off three or four or more clumsy branches a few feet from the 

 ground, as shown in the illustration. 



Another striking form seen here for the first time is the Fouquiera 

 columnaris shown in Plate 7, and which becomes more abundant on the 

 inland plateau. Although in greater dimensions, some 40 feet in height 

 and 15 to 18 inches in diameter at the base, these strange forms were 

 readily cut down with the back of my geological hammer, and showed 

 in cross section a structure not greatly unlike that of our ordinary 

 Eastern sunflower {HeUanthus annuus Linnteus) in that they have a 

 thin exterior or rind of a greenish white color and an interior core of 

 white pith-like material. 



The numerous branches, which are about the size of an ordinary lead 

 pencil, pass directly through the hard, woody rind into the pith. When 

 the plant dies, the limbs fall out, the pith shrinks away and decays, 

 leaving the trunks in the form of collapsed elongated cylinders full of 

 spirally- arranged perforations. These branches are very abundant, and 

 project uniformly in every direction, sometimes to a distance of 2 feet 

 or more. They are stiff, harsh, and thorny, and it was found possible 

 to gain access to the trunk without seriouslj^ tearing the flesh only by 

 turning up one's coat collar, putting on gloves, bowing the head, and 

 backing in. Even then the work of cutting through the bark is disa- 

 greeable, though the bark or rind is itself thin and tender. 



A landscape of these pole like forms, with their thorny branches and 

 few small, brittle, thick, yellow green leaves is weird in the extreme, 



