LINN2EAN CLASSES. 247 



Corydolis and Fumitory ; Octandria by Polygala ; 

 and Decandria by Glycine, Vetch, Locust, and most 

 of the Papilionaceous flowers. In this class the Le- 

 gume presents the most indubitable marks of distinc- 

 tion. A few genera have their stamens all united, but 

 as they possess every other character, which would 

 entitle them to rank in the present class, botanists have 

 never ventured to separate them. 



The class Polydelphia has three orders, distinguished 

 by the number and insertion of the stamens. This 

 class has been rejected by many late writers, and most 

 of the plants which it embraces, range under the 

 twelfth and thirteenth classes of the Linnaean system. 



The class Syngenesia has five orders. In the first, 

 {equalis) the florets are all perfect and fertile, being 

 ligulate as in the Dandelion, and tubular as in the 

 Thistle. The second order {superflua) contains dis- 

 coid and radiate flowers. The marginal florets ofthe for- 

 mer are either obsolete or inconspicuous, and the whole 

 are so arranged as to form a flat or conical surface, as 

 in Tansey, Everlasting, and Artemisia. The marginal 

 florets of the latter are ligulate, forming conspicuous 

 and diverging rays as in the Daisy, Aster and Chrysan- 

 themum. The third order (frustranea) has its mar- 

 ginal flv-trets unfertile though sometimes furnished with 

 the rudiments of pistils, and this alone will serve to 

 distinguish it from the preceding orders. The Sun- 

 flower, Sweet-Sultan, and Blue-Bottle are common 

 examples. Dr. Smith is inclined to abolish this order 

 and to rank those genera which have the rudiments of 

 pistils in their radiant florets, with their near relations 

 in the preceding order. 



The fourth order {necessaria) has stamens in its dis- 

 cal florets, and pistils in those ofthe ray, so that both 



