Page:Popular Science Monthly Volume 40.djvu/70

 in taking the number of existing species to be somewhat above one hundred and ten thousand.

Now, if we should make a comprehensive list of all the flowering plants which are cultivated on what we may call a fairly-large scale at the present day, placing therein all food and forage plants, all those which are grown for timber and cabinet woods, for fibers and cordage, for tanning materials, dyes, resins, rubber, gums, oils, perfumes, and medicines, we could bring together barely three hundred species. If we should add to this short catalogue all the species which, without cultivation, can be used by man, we should find it considerably lengthened. A great many products of the classes just referred to are derived in commerce from wild plants, but exactly how much their addition would extend the list it is impossible in the present state of knowledge to determine. Every enumeration of this character is likely to contain errors from two sources: first, it would be sure to contain some species which have outlived their real usefulness, and, secondly, owing to the chaotic condition of the literature of the subject, omissions would occur.

But after all proper exclusions and additions have been made