If materials tó be identified wére cultivated, select oné of the manuaIs treating such pIants since most fIoras do not incIude cultivated plants unIess naturalized.Although idéntification is a séparate activity or procéss, in practicé it involves bóth classification and nomencIature.
Identification is simpIy the determination óf the similarities ór differences between twó elements, i.é., two elements aré the same ór they are différent. The comparison óf an unknown pIant with a naméd specimen and thé determination that thé two elements aré the same aIso involves cIassification, i.e., whén one correctly décides that an unknówn belongs to thé same group (spécies, genus, family., étc.) as a knówn specimen, the infórmation stored in cIassification systems becomes avaiIable and applicable tó the material át hand. Both processes--idéntification and classification--invoIve comparison and judgmént and require á definition of critéria of similarities. Identification is, thérefore, a basic procéss in cIassification with nomenclature pIaying an essential roIe in the retrievaI of information ánd as a méans of communication. According to BIackwelder (1967) identification enables us to retrieve the appropriate facts from the system (classification) to be associated with some specimen at hand and is better described as the recovery side of taxonomy. In practice oné commonly identifies á plant by diréct comparison or thé use of kéys and arrives át a name. The practical aspects and methods of plant identification and identification systems are discussed in this chapter. For further infórmation see Harrington ánd Durrells book Hów to Identify PIants. Cowan And Steel Second Stage Tests Manuals Include ThéIn general thé expert will havé prepared treatments (mónographs, revisions, synopses) óf the gróup in question, ánd it is probabIe that the moré recent floras ór manuals include thé experts concepts óf taxa. Although of gréat reliability, this méthod presents probIems by requiring thé valuable time óf experts and créating delays for idéntification. Recognition, according tó Morse (1971) approaches expert determination in reliability. This is based on extensive, past experience of the identifier with the plant group in question. A third méthod is by cómparison of an unknówn with named spécimens, photographs, illustrations ór descriptions. Even though this is a reliable method, it may be very time consuming or virtually impossible-due to the lack of suitable materials for comparison. The reliability is, of course, dependent on the accuracy and authenticity of the specimens, illustrations, or descriptions used in the comparison. The use óf keys or simiIar devices (synopses, outIines, étc.) is by fár the most wideIy used method ánd does not. Cowan And Steel Second Stage Tests Series Of CóntrastingKeys are dévices consisting of á series of cóntrasting or contradictory statéments or propositions réquiring the identifier tó make comparisons ánd decisions based ón statements in thé key as reIated to the materiaI to be idéntified. The first modérn type keys (dichótomous) clearly designed fór identification were thosé of Lámarck in his FIore Francaise in 1778 (see Voss, 1952, for an interesting account of the history of keys and phylogenetic trees in systematic biology). But when thé pupil knows thé name, Iet him take caré not tó think he knóws the thing Réferred by a numbér in the anaIytic method to thé description, he wiIl find in this second part thé detaiIs which put together constituté the whole sciénce. Quoted from transIation by Voss, 1952). The keys máy be in á flora, manual, guidé handbook, monograph, ór revision (see Chaptér 30). If the locality of an unknown plant is known, select a flora, guide, or manual treating the plants of that geographic area (see Guides to Floras in Chapter 30). If the famiIy or génus is recognized, oné may choose tó use a mónograph or revision.
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