A DESERT FRUIT. 57 



steered his wandering bark to the sandy shores of Cat's 

 Island in the Bahamas. (I have seen Cat's Island with 

 these very eyes, and can honestly assure you that its 

 shores are sandy.) But this is only one among the many 

 pardonable little inaccuracies of painters, who thrust 

 scarlet geraniums from the Cape of Good Hope into the 

 fingers of Aspasia, or supply King Solomon in all his 

 glory with Japanese lilies of the most recent introduction. 

 At the present day, it is true, both the prickly-pear 

 cactus and the American agave (which the world at large 

 insists upon confounding with the aloe, a member of a 

 totally distinct family) have spread themselves in an 

 apparently wild condition over all the rocky coasts both 

 of Southern Europe and of Northern Africa. The alien 

 desert weeds have fixed their roots firmly in the sun- 

 baked clefts of Ligurian Apennines ; the tall candelabrum 

 of the western agave has reared its great spike of branch- 

 ing blossoms (which flower, not once in a century, as 

 legend avers, but once in some fifteen years or so) on all 

 the basking hillsides of the Mauritanian Atlas. But for 

 the origin, and therefore for the evolutionary history, of 

 either plant, we must look away from the shore of the 

 inland sea to the arid expanse of the Mexican desert. 

 It was there, among the sweltering rocks of the Tierras 

 Calientes, that these ungainly cactuses first learned to 

 clothe themselves in prickly mail, to store in their loose 

 tissues an abundant supply of sticky moisture, and to 

 set at defiance the persistent attacks of all external 

 enemies. The prickly pear, in fact, is a typical instance 

 of a desert plant, as the camel is a typical instance of a 

 desert animal. Each lays itself out to endure the long 



