PLANTS. 215 



repetition, we substitute signs for words, and thus secure 

 brevity.* 



Q Annual Plants. 



$ Biennial Plants. 



U Perennial Plants. 



8 Shrubs or Trees. 



* Botanists have successively employed different artificial systems 

 and natural methods in the classification of plants. "We therefore intro- 

 duce to the notice of our readers three synoptic tables, as arranged 

 by the three celebrated naturalists, namely, Linnaeus, De Candolles ( 

 and Jussieu. Linnaeus's method has been already mentioned. The 

 learned and sagacious Jussieu, who first -elaborated and published a 

 natural system, in 1798, arranged the vegetable kingdom in fifteen 

 classes and one hundred orders or families. Endlicher, in 1840, gives 

 no less than ^sixty-one classes, and two hundred and seventy-seven 

 orders, with tribes and sub-tribes almost innumerable. 



In an exposition of the natural system, some authors (Jussieu and 

 Endlicher) commence with the lower extremity of the series, and end 

 with the higher ; others, as Candolle, pursue the opposite, beginning 

 with the most perfect flowering plants, and concluding with the lowest 

 grade of flowering plants. The first mode possesses the advantage of 

 ascending by successive steps from the simplest to the most complex 

 structure ; the second, that of passing from the most complete and 

 best understood to the most reduced and least known forms ; or, in 

 other words, from the easiest to the most difficult, and is, therefore, 

 the best plan for the student. PROF. GRAY. TV. 



