VARIETIES. 



469 



given to these distinctions, cannot be taught in the science of 

 botany, though, for the purposes of horticulture, they have their 

 use. 



The Virtues and Uses of plants furnish no specific difference ; 

 and the distinctions, therefore, of physical writers are not always 

 to be depended on. * 



The Duration of plants is no sure mark of distinct. species, 

 being often owjng rather to the place, than to the nature of the 

 plant. In warm regions, plants that are annual with us will be- 

 come perennial,... or arborescent, as is found in Trop^olu m,... Be- 

 ta,. ..Majorana,... Malva Arborea, &c ; and on the contrary, 

 cold regipns will occasion perennial plants to become annnal, as 

 is observed in Ricinus,...Mirabilis*, &c. 



Multitude, or quantity, is an accidental circumstance in plants,, 

 and cannot conclude any thing, whether the increase be of the 

 plant itself, or of its roote, stents, leaves, or fructification. 



Pubescence is an uncertain mark, as by culture and change 

 of soil, plants are subject to lose as well their spinas as their 

 hair or down. 



Leaves, though they for the most part furnish most elegant 

 specific differences, as has been observed in the last Chapter, are 

 yet subject to luxuriation in the same species, which must be 

 carefully distinguished. This may respect their opposition and 

 composition, and also their being crisp (curled),... or bullate (blad- 

 dery). 



In respect to Opposition, opposite leaves will sometimes be- 

 come ternate,...quuternate,...ox quinate, growing by threes, fours, 

 or fives ; and then the stem also from Quadrangular, square, 

 \yill become polygonous, of many sidesf. 



* Ricinus and Mirabilis, are naturally perennial plants, and are only killed by 

 frost in cold countries. Author. 



f- Lysimachia lutea major joliis ternis (Tourn.) 

 Lysimachia lutea majw foliis quaternis (TournJ 



