TERMINOLOGY AND NOMENCLATURE. 489 



remembrance of having experienced it before. Hence it is only the im- 

 pressions on the outward senses, or those inward feelings which are con- 

 nected in a very obvious and uniform manner with outward objects, that 

 are really susceptible of an exact descriptive language. The countless va- 

 riety of sensations which arise, for instance, from disease, or from peculiar 

 physiological states, it would be in vain to attempt to name ; for as no one 

 can judge whether the sensation I have is the same with his, the name can 

 not have, to us two, real community of meaning. The same may be said, 

 to a considerable extent, of purely mental feelings. But in some of the 

 sciences which are conversant with external objects, it is scarcely possible 

 to surpass the perfection to which this quality of a philosophical language 

 has been carried. 



"The formation* of an exact and extensive descriptive language for 

 botany has been executed with a degree of skill and felicity, which, before 

 it was attained, could hardly have been dreamed of as attainable. Every 

 part of a plant has been named ; and the form of every part, even the most 

 minute, has had a large assemblage of descriptive terms appropriated to 

 it, by means of which the botanist can convey and receive knowledge of 

 form and structure, as exactly as if each minute part were presented to 

 him vastly magnified. This acquisition was part of the Linna?an re- 

 form..... ' Tournefort,' says Decandollc, 'appears to have been the first 

 who really perceived the utility of fixing the sense of terms in such a way 

 as always to employ the same word in tiie same sense, and always to ex- 

 press the same idea by the same words; but it was Linnaeus who really 

 created and fixed this botanical language, and this is his fairest claim to 

 glory, for by this fixation of language he has shed clearness and precision 

 over all parts of the science.' 



" It is not necessary here to give any detailed account of the terms of 

 botany. The fundamental ones have been gradually introduced, as the 

 parts of plants were more carefully and minutely examined. Thus the 

 flower was necessarily distinguished into the calyx, the corolla, the sta- 

 mens, and the pistils; the sections of the corolla were termed petals by 

 Columna; those of the calyx were called sepals by Necker. Sometimes 

 terms of greater generality were devised ; slb perianth, to include the calyx 

 and corolla, whether one or both of these were present ; pericarp, for the 

 part inclosing the grain, of whatever kind it be, fruit, nut, pod, etc. And 

 it may easily be imagined, that descriptive terms may, by definition and 

 combination, become very numerous and distinct. Thus leaves may be 

 called pinnatijid, pintiatipartite, pinnatisect, pinnatilohate, palrrMtifid, pal- 

 matipartite, etc., and each of these words designates different combinations 

 of the modes and extent of the divisions of the leaf with the divisions of 

 its outline. In some cases, arbitrary numerical relations are introduced 

 into the definition : thus, a leaf is called bilobate, when it is divided into 

 two parts by a notch ; but if the notch go to the middle of its length, it 

 is bifid; if it go near the base of the leaf, it is bipartite; if to the base, it 

 is bisect. Thus, too, a pod of a cruciferous plant is a siliqua, if it is four 

 times as long as it is broad, but if it be shorter than this it is a silicula. 

 Such terms being established, the form of the very complex leaf or frond 

 of a fern (Hymenophyllum Wilsoni) is exactly conveyed by the following 

 phrase : ' fronds rigid pinnate, pinnae recurved subunilateral, pinnatifid, the 

 segments linear undivided or bifid, spinuloso-serrate.' 



\ 



* History of Scientific Ideas, ii., 111-113. 



