There are in general four kinds of trees from which timber suitable for structural purposes may be obtained, which differ from each other in their manner of growth and in the details of their structure, as well as in their adaptability to building work, but of these . only two, the so-called broad-leaved trees and the needle-leaved trees, yield timber used in any great quantity for building. The other two are suitable for structural work but for one reason or another have not been extensively utilized as yet except in the immediate neighborhood of the places where they grow. This is especially true of the bamboos, which grow in abundance in China and the Philippine Islands and are there used extensively for building purposes, but which have never as yet been introduced into other countries, although the wood has certain characteristics which might make it very suitable for use in some locations, and the tree could probably be made to grow in any warm climate such as that of the southern states. There is another class of tree of which the palms are the most well-known representatives, but the use of the lumber cut from these trees is very limited.