196 WEEDS AND THE1K CHARACTERISTICS. 
of becoming altogether extinct. I remember the venerable explorers, 
Ecklon ancf Zeyher, taking me to>e a few Silver-trees (Leucadendron 
argenteum), which, they assured me, were the only specimens m South 
Africa. Dr. Hooker, in his suggestive paper « On the Struggle for 
Existence amongst Plants" ('Popular Science Review,' April 1867), 
has well pointed out the rapid spread of European species in New 
Zealand, and the displacement of the indigenous. The alterations 
wrought in Europe by the naturalization of foreign plants are familiar 
to us^ll, and many other parts of the inhabited glohe might be pointed 
out where the same phenomenon is observable. Eoreign plants deport 
themselves towards the indigenous as an invading army does towards 
the inhabitants of a hostile country. Before the bulk of the army 
advances, outposts make their appearance, consisting of the most daring 
and hardy fellows. In the vegetable kingdom this office is performed 
by the weeds, and it is on them that I shoidd like to make a few re- 
4 
marks. 
• 
Considering that weeds are found in every part of the inhabited 
world, it is singular that so few languages have a full equivalent of the 
term " weed" and that so useful an idea as that popularly embodied 
in it should not have been, long ere this, translated into science. The 
Latin " herbal or Spanish "i/ierba," certainly does include our "weed; 
but whilst every weed is a herb, not every herb is a weed. What, then, 
is the real meaning of "weed"? Dictionary writers do not help us 
much by qualifying weed as a mean or troublesome herb, for j ie 
popular mind associates with the nature of a weed several other cha- 
racteristics not mentioned by them. We talk of plants bearing • 
weedy look," and though most of us know what that means, nobody 
has as yet made it clear to those who do not know. The term wee J 
would be misapplied to the Aloes, but fit exactly the generality of ■ »c 
Ahinea. We wovdd never say of the Heather that it had a weec V 
look; in fact, the term would never suggest itself in connection Wi 
that species. The vegetation of New Holland could not be descn et, 
* I may here state that this article was written on the Atlantic •"fj^ * 
fog a paper of Dr. Hooker's, " On the Struggle for Existence among Y °^^ 
in the 'Popular Science Review' for April, 1867, which I found on ^f^ 
Koyal Mail Steamer 'Douro,' in the "Virgin Islands, West Indi . ' J*^ 
the views advanced here are, as it were, a further development of ideas 
upon by D*. Hooker. 
