THE STEM. 



Fig 



Perfoliate Stem, (Caulis perfoliatus.) 

 Fig. 17. The stem passes through the 

 leaf, or the leaf surrounds the stem. Ex.. 

 Perfoliate Bellwort, (Uvularia perfoliate) 



Some trees are provided with several stems or props, by 

 which their branches are supported and kept in a horizontal 

 position. The Black Mangrove, (Rhizophora mangle,) which 

 grows in the West Indies, is an example. The limbs spread 

 to such a distance from the trunk as to require support, other- 

 wise they would bend to the ground, or be broken by their 

 own weight, both of which, nature has contrived the means 

 of preventing. When the branches are no longer capable of 

 supporting themselves, they send forth soft, lax strings in 

 many places, which grow rapidly downwards, and soon reach 

 the earth, where they take root. In a few months they begin 

 to give support to the branches above, and finally beco.iie 

 capable of sustaining all the weight required. 



There is also another tree, which grows in the East Indies, 

 whose branches are propped in the same manner. This is 

 the celebrated Banyan tree, (Ficus Indica,) and on account 

 of its great size affords the most remarkable instance of this 

 kind of support. Its mode of increase is precisely like that 

 of the mangrove above described. The eastern traveller, 

 Forbes, describes one of these trees which he visited on the 

 bank of a river in India. A part of it had been swept away 

 by an inundation of the river, but the principal stems still 

 remained, and occupied a space which measured about two 

 thousand feet in circumference, though many of the branches 

 which had not yet sent down steins extended much farther. 

 The large trunks of this tree amounted to three thousand and 

 fifty in number, besides which there were as many more of 

 a smaller size. On one occasion this huge Banyan had given 

 shelter to an army of seven thousand men. 



What, is meant by a perfoliate stem ? In what manner are the limbs of 

 the black mangrove said to support themselves ? What is said of the 

 size and shape of the Banyan tree ? 



