XXIV INTRODUCTION TO BOTANY. 
1838. Classes, Orders, Genera, and their sub-divisions, are called natwral, when, 
in forming them, all resemblances and differences are taken into account, valuing 
them according to their importance ; artijicial, when resemblances and differences 
in some one, or very few particulars only, are taken into account. 
IV. Couttrction, PRESERVATION, AND EXAMINATION OF PLANTS. 
_ 184, Though plants can be most easily and satisfactorily examined when freshly 
gathered, yet as time will rarely admit of this being done, and as it is also desirable 
to compare with other plants previously observed or collected, specimens must be 
selected for leisurely observation at home, and for preservation for future reference. 
185. A botanical Specimen should be, as much as possible, an epitome of the spe 
cies which it represents, and if the species be variable, several specimens are neces- 
sary. To be perfect, it should have root, stem, leaves, flowers (both open and in bud), 
and fruit (both young and mature). It is not always, however, possible to gather 
such complete specimens ; but the collector should aim at completeness. F 
such as leaves without flowers, or flowers without leaves, are of comparatively little 
use, ; 
186. All small plants, not exceeding 15 inches in height, should be plucked up by 
the roots, the whole plant forming a single specimen ; or, if a many-stemmed plant, 
or one much branched near the base, and which if dried whole would make too dense 
a mass of branches or stems, it may be divided, at the origin of the branches, into 
‘several SpeOiMen sen por iss pei e  e eei ae ve Me 
187. If the plant to be dried be of greater length than 15 inches, and if it be 
thought desirable—either from the lower leaves differing from the upper, or from 
the branches being long and naked—to preserve the stem wnbroken, the specimen 
may be folded in lengths of 15 inches. This is often done with Grasses, Sedges, and 
Ferns : and should be done in the cases of all long-stemmed, Jax-leaved herbaceous, 
and with tall bulbous plants, in order to preserve an indication of their habit. = __ 
188. Herbaceous plants of large size, and specimens of the branches of shrubs and 
trees, must be broken into pieces, say 10-18 inches long, the length varying with 
the nature or ramifications of the plant. The object is to preserve as much of the 
peculiar aspect of the plant as is possible. 
189. At least a dozen specimens of each plant should (when practicable) be ga 
thered, for the purpose of exchanging with other botanists. A collector can scarcely 
have too many duplicates, especially when his explorations are made in a little-fre-_ 
quented district. Many collect much more extensively. : 
190. The collector should be provided with : em 
1. A quantity (at his discretion) of any stout, coarse, unsized paper, of unt 
form dimensions, say 12 inches by 18. Old newspapers answer the put- 
pose ; and common packing paper, whity-brown or brown, is most excel- 
lent. Blotting paper is much too tender and expensive. ; 
2. A smaller quantity of very thin, unglazed paper, or chemist’s filtering paper 
for drying plants with delicate corollas, (see 198). 
8. Several flat, perforated boards, the size of the paper. Open wooden frames, 
_. — with cross-bars, or frames of strong wire-work lattice, are better than 
hoards, as they permit a freer evaporation. es 
4. A light portfolio of pasteboard, covered with calico, fitted up with 12-20 
___ Teave& of strong brown paper, furnished with a strap and buckle for 
= ee lingi Ribas Ss abana, beta eae 
ort than the old-fashioned collecting-box. The specimens, a5 8% 
thered, are p between the leaves, and may be crowded /, it 
