84 SPECIES. 



2. Colour, although so conspicuous a mark in flowers, is so va- 

 riable, that it is never depended on as a character. 



Take, for an example of Generic and Specific char- 

 actors, the family of Lilies, which in Practical Works 

 is arranged as follows. 



Class VI. HEXANDRIA, six stamens. 



Order I. MOJVOGYJVI4, one style. 



Genus LILIUM. LILY. 



Generic character. Calyx none ; corolla inferiour, 

 six petalled, the petals with a longitudinal groove from 

 the middle to the hase. 



Species 1. LIUUM CANADENSE. Canada Lily. Com- 

 mon Yellow Lily. 



Specific Character. Leaves in whorls ; flowers ter- 

 minal, drooping, petals spreading. 



Species 2. LIUUM PHIIADELPHICUM. Common Red 

 Lily. 



Specific Character. Leaves in whorls; flowers erect ; 

 corolla hell-shaped, petals with claws. 



Observation. I . The Cabbage, Turnip, and Kale, are so many 

 species of one genus, Brassica. The Apple, Pear, and Quince, 

 of the genus Pyrus. The Plum and Cherry are species of the 

 genus Prunm. The Currant and Gooseberry are species of Ribes. 



. A diagnostic or discriminating description of a plant, of 

 which the above is an example, is liable to differ very much 

 from a general or entire description. In a discriminating de- 

 scription such points only are noticed as are sufficient to distin- 

 guish the plant successively, in classes, orders, genera, and spe- 

 cies from all others In distinguishing species especially, very 

 minute marks are frequently of necessity made essential, because 

 they are the only definable points in which the species differs 

 from all others, while some marks which are prominent, pass un- 

 noticed because they are common to several. 



A per/eft or complete description of an individual, made out with- 

 out any reference to other plants, touches every point and gives, 

 as it were, a complete picture of the whole plant. Such a de- 

 scription has been called the Natural Character of the Species. 



It is often very convenient to note down something 1 like an en- 

 tire description of plants, as we find them, in order to retain their 

 characters until we can fir.d their distinguishing description, or in 

 other words, their generic and specific characters. 



