68 THE HARMONIES OF NATURE. 



defensive weapons attain in the tropical zone. The cactuses, the 

 acacias, and many of the palm-trees, bristle with sharp-pointed 

 shafts, affording them ample protection against the attacks of 

 hungry animals, so that they might appropriately be called 

 vegetable hedgehogs or porcupines. 



The melon-cactus of the South American llanos or savannahs 

 conceals its juicy pulp, pleasant to man and beast, under one of 

 these formidable panoplies. Guided by an admirable instinct, 

 the wary mule strikes off with his fore-feet the long sharp thorns 

 of this remarkable plant, the emblem of good nature unde/ a 

 forbidding exterior, and then cautiously approaches his lips to 

 feast upon the refreshing marrow. Yet, in spite of every pre- 

 caution, the attempt to quaff from these alluring sources is fre- 

 quently attended with danger, for mules are often met with that 

 have been lamed by wounds from the formidable prickles of the 

 cactus. 



The black twigs of the buffalo-thorn (Acacia latronum), a low 

 shrub abounding in northern Ceylon, are beset at every joint 

 by a pair of thorns, set opposite each other like the horns of an 

 ox, as sharp as a needle, from two to three inches in length, and 

 thicker at the base than the stem on which they grow ; and the 

 Acacia tomentosa, another member of the same numerous genus, 

 has thorns so large as to be called the jungle-nail by Europeans, 

 and the elephant-thorn by the natives. In some of these thorny 

 plants, the spines grow, not singly but in branching clusters, 

 each point presenting a spike as sharp as a lancet ; and where 

 .these shrubs abound, they render the forest absolutely impassable 

 even to animals of the greatest size and strength. 



The rattans and bush-ropes impede the wanderer's progress 

 not only by the tough cordage they twine from tree to tree, but 

 also by the strong hooks and thorns with which they are gene- 

 rally armed, so that every attempt to force a passage would be 

 severely punished with torn clothes and bloody hands, and large 

 knives or heavy scythe-like axes are necessary to clear the way. 



Some plants are protected by thorns only up to a certain 

 height. The Caryota horrida, a palm which raises its crown 

 fifty feet above the surface of the soil, is so thickly studded with 

 formidable thorns to the height of six or eight feet, that it is 

 hardly possible to see the bark ; further upwards, where defence 

 is no longer necessary, the trunk is unarmed. The thorny 



