DESCRIPTIVE BO TANS'. PART I. 



tural groups will be instantly referred to thsir proper 

 class and order, without the necessity of searching 

 for the characters upon which their arrangement de- 

 pends. It will be soon seen that Triandria, Hex- 

 andria, and Gynandria contain the great bulk of 

 the Monocotyledones, and that there are very few 

 of this natural class among the other artificial classes. 

 This circumstance is connected with the ternary ar- 

 rangement of the subordinate parts of the floral 

 whorls, to which we have alluded (art. 120.). On the 

 other hand, tlie great bulk of Dicotyledons are included 

 in those classes where some trace or other of a quinary 

 disposition is observable. Thus, Pentandria, Decan- 

 dria, Icosandria, and Polyandria are large classes an- 

 swering to this description ; and Syngenesia, which 

 is the largest of any, has always five stamens, and the 

 corolhr generally exhibit a tendency to a subdivision 

 into five separate petals, indicated by five teeth at the 

 end of the florets. Didynamia is eminently irregular ; 

 but even here, the normal character of the species seems 

 to repose upon a quinary arrangement, which is some- 

 times manifested by a monstrous development of the 

 suppressed organs, as in the varieties termed " Peloria," 

 of the genera Antirrhinum and Linaria (see art. 114.). 

 Tetradynamia is not unsymmetrical, but equally irregu- 

 lar, as regards the more usual characteristic of a dico- 

 tyledonous flower. 



