] OUTLINES OF BOTANY. 
plant besides perhaps some occasional protection against injurious atmo- 
spheric influences, but the root-hairs (216) are active absorbents, the hairs 
on styles and other parts of flowers appear often materially to assist the - 
transmission of pollen, and the exudations of glandular hairs (175, 2) are 
often too copious not to exercise some influence on the phenomena of vege- 
tation. The whole question, however, of vegetable exudations and their 
influence on the economy of vegetable life, is as yet but imperfectly un- 
derstood. : 
Cuar. IV. CortecTion, PRESERVATION, AND DETERMINATION OF PLANTs. 
224. Plants can undoubtedly be most easily and satisfactorily examined 
when freshly gathered. But time will rarely admit of this being done, and 
it is moreover desirable to compare them with other plants previously ob- 
served or collected. Specimens must, therefore, be selected for leisurely 
observation at home, and preserved for future reference. A collection of 
such specimens constitutes an Herbarium. 
225. A botanical Specimen, to be perfect, should have root, stem, 
leaves, flowers (both open and in bud) and fruit (both young and mature). 
It is not, however, always possible to gather such complete specimens, but 
the collector should aim at completeness. Fragments, such as leaves without 
flowers, or flowers without leaves, are of little or no use. 
226. If the plant is small (not exceeding 15 in.), or can be reduced to 
that length by folding, the specimen should consist of the whole plant, in- 
cluding the principal part of the root. If it be too large to preserve the 
whole, a good flowering braneh should be selected, with the foliage as low. 
down as can be gathered with it; and one or two of the lower stem-leaves 
or radical leaves, if any, should be added, so as to preserve as much as 
possible of the peculiar aspect of the plant. 
227. The specimen should be taken from healthy uninjured plants of - 
a medium size. Orif a specimen be gathered because it looks a little dif- 
ferent from the majority of those around it, apparently belonging to the 
same species, a specimen of the more prevalent form should be taken from 
the same locality for comparison. 
228. For bringing the specimens home, a light portfolio of pasteboard, 
covered with calico or leather, furnished with straps and buckles for closing, 
and another for slinging on the shoulder, and containing a few sheets of 
stout coarse paper, is better than the old-fashioned tin box (except, perhaps, 
for stiff, prickly plants, and a few others). The specimens as gathered are 
placed between the leaves of paper, and may be crowded together if not left 
long without sorting. 
229. If the specimen brought home be not immediately determined when 
fresh, but dried for future examination, a note should be taken of the time, 
p-ace, and situation in which it was gathered; of the stature, habit, and 
other particulars relating to any tree, shrub, or herb of which the specimen 
is only a portion; of the kind of root it has; of the colour of the flower; 
or of any other particulars which the specimen itself cannot supply, or 
which may be lost in the process of drying. These memoranda, whether 
taken down in the field, or from the living specimen when brought home, 
should be written on a label attached to the specimen or preserved with it. 
