BIOLOGY. 831 



The astringent gum, known by the name of "kina," is obtained 

 by an incision in the bark of this ti-ee. Tlie flowers are white and 

 balsamic, and are much liked by the bees. The Eucalyptus is 

 tajj-rooted ; that is to say, its roots penetrate vertically into the 

 ground. It is an evergreen, and the leaves resemble those of tlie 

 hmrel. When the tree has already the height of about forty 

 " meti-es," the lateral branches develop themselves in away which 

 is really extraordinary. Some of them measure about thirty 

 " metres " in length. Imagine a tree higher than one hundred 

 "metres," the top of which has a circumference of nearly two 

 hundred " metises," as large as the roof of a church. The seed of 

 the Eucalyptus is very small, and looks like tobacco-seed. Its 

 lateral branches are very numerous, and closely collected around 

 the principal stem. 



BOTANY OF BRAZIL. 



The following facts are from notes taken of Prof. Agassiz's lec- 

 tures before the Lowell Institute, Boston, Mass., in October, 1866, 

 from his personal examination in Brazil : — 



In speaking of the extraordinarily profuse vegetation of the 

 valley of the Amazon, Professor Agassiz said it covered the whole 

 surface of the land, and encroached upon the water. Indeed, the 

 quantity of water plants is as remarkable as that of terrestrial 

 plants. The density of the land vegetation is so great that tiie 

 only means of traversing the countr^^is by the water courses, and, 

 when the traveller leaves these, he must cut his way with the axe ; 

 so that, however civilization may extend hei'e, there can never be 

 any extensive land communication, on account of the great 

 exi^enditui-e which would be required for bridges. 



Words cannot express the variety, beauty, and combinations of 

 this vegetation. One of its most striking characteristics is its het- 

 ei'ogeneity. There are not simply a few kinds found together, 

 presenting sameness and monotony, as at the north. On the con- 

 trary, there are hardly ever two trees of the same kind, or two 

 plants of the same species, found side by side. The trees do not 

 stand alone, in open spaces, but are clothed and interlaced with 

 vines, creepers, and parasites, hard to penetrate. This character 

 of the vegetation extends over the whole basin. In the lakes the 

 aquatic plants grow so thickly that the traveller, threading his 

 way among them with a boat, sails for miles without seeing either 

 water or earth. 



He observed that the most prominent feature of the Amazonian 

 vegetation is the presence of innumerable palms, in the form of 

 trees, bushes, and creepers. We look in vain for pines, maples, 

 oaks, willow, and other trees familiar to us in the United States. 

 The aspect of vegetation, the character of the trees, and their 

 combinations, change as we travel. Of the i^alms, one variety 

 rises to the height of one hundred feet before sending out its 

 leaves, which crown its top like a dome. Another variety sends 

 out its leaves immediately from the root. The flowers and fruit 

 of the palms also vaiy. Some of them bear nuts of peculiar form, 

 others berries, and the fruit of some of them strongly resembles 



