64 PHENOMENA OF PLANT-LIFE. 



In India, it is customary to make incision into the wood of 

 trees near the top, from which, during the cool months, the sap 

 flows freely. From the common wild date-palm the annual 

 yield of sap is about two hundred pounds, containing some 

 eight pounds of sugar, or four times the average product of 

 the sugar maple. Much the larger proportion of palm sap is 

 obtained, however, from the large branching flower-stalks of 

 ^the inflorescence. These are produced in the axils of the 

 immense leaves or fronds, and before they burst the spat-he in 

 which they are enveloped, they are carefully bound together 

 with pieces of palm-leaf. These buds are then beaten every 

 morning with sticks and a thin slice removed from the tip of 

 the axis of inflorescence. From the freshly exposed surface 

 the sweet sap runs very abundantly for several months. 

 Indeed, some species continually send out new flower-stalks, 

 which are constantly bled until, after two or three years, the 

 tree dies from exhaustion. 



But the most remarkable flow of sap is that of the Agave 

 Americana, or century plant. This is the largest herbaceous 

 plant known, the leaves of one in the Durfee Plant-House 

 being eight feet long and of immense weight. In Mexico, the 

 sap of this species furnishes the favorite beverage of the 

 people. This is called pulque, and has a most detestable odor 

 of carrion and a slightly 'acid taste. The Mexicans are very 

 fond of it, and natives of other countries soon learn to love it 

 and then prefer it to claret. The sap is procured by cut- 

 ting out the bud of the inflorescence which appears in the 

 centre of the massive crown of leaves, and, if undisturbed, 

 develops into a flower-stalk from thirty to forty feet high and 

 covered with thousands of blossoms. The cavity made by 

 removing the bud is speedily filled with a sweet sap, and the 

 total amount from one plant is stated by Von Humboldt to be 

 from tvfelve to sixteen hundred pounds. The plant then 

 dies from exhaustion. 



It is impossible to give any satisfactory explanation for 

 these extraordinary phenomena. It is easy to state that 

 these plants produce large quantities of starch and sugar pre- 

 paratory to flowering, but why should they continue to flow 

 so long after the trees are cut down or the flower buds 

 removed ? 



