DESCRIPTIVE BOTANY. 155 



It follows from this, that the character of a species whicli 

 is the only one of the genus, cannot be dehneated. Such 

 plants are rather explained by description. 



236. 



The specific character derives its elements from every 

 part of the plant, the properties of which are invariable. 

 The nature of the root, — the qualities of the stem and 

 branches, — the forms of the leaves, — the armour and sup- 

 ports, — the form of the calyx and corolla, — the relations of 

 the nectaries, filaments, pistils, ovaria, and fruit, — these are 

 the true elements of which the specific character is properly 

 compounded. Even the integuments of the parts nmst not 

 be neglected, in as far as they are constant. 



237. 



On the other hand, neither colour nor the size of parts,, 

 neither smell nor taste, neither the situation nor the frequency 

 of plants, belong properly to these elements. Nevertheless, 

 use may be made even of these things under certain circum- 

 stances. 



Colour, in the first place, is taken into consideration, when 

 it is not only constant, but when, among a few characters, it 

 is also the most remarkable ; on which account, in the lower 

 plants particularly, the colour is very correctly defined. In 

 more perfect plants, we usually state merely that the parts 

 are diff*erently coloured, commonly by the words colof'atm, 

 maculatuSj and such like. 



The measure and size of parts do not indeed properly 

 belong to the specific character, in so far as it is positively 

 expressed, because these qualities are subject to change. But 

 the relative size, or the proportion of the parts to one ano- 

 ther, is usually viewed as one of the most important ingre- 

 dients of the specific character. That the corolla projects 

 above the calyx, or is shorter than it, — that the filaments are 

 longer than the pistil, or the reverse, — that the leaf-stalks ex- 

 ceed the leaves in length, — all these things must be taken into 

 the specific character. It is also usual, when an organ, in rcla- 



