72 ORDERS. 



3. POLYGAMIA FRUSTRANEA, florets of the disk per- 

 fect ; those of the ray abortive, being either destitute of 



a pistil, or having only an ineffectual one. Ex. Blue- 

 bottle, Centaurea; Sunflower, Helian thus. 



4. PO;LYGAMIA NECESSARIA, florets of the disk, bar- 

 ren, having stamens only ; those of the ray fertile, hav- 

 ing pistils only. Ex. Marygold \ Everlasting, Gnaph- 

 alium* 



5. POLYGAMIA SEGREGATA, each floret having a ca- 

 lyx proper to itself, besides a common calyx includ- 

 ing them all. Ex. Globe Thistle, Gundelia. 



Observation* 1. Linnaeus had a 6th order, named Monogamia, 

 consisting- of simple flowers with united anthers, as Violet and //o- 

 belia ; but as these have no affinity to the compound flowers, 

 and as the union of their anthers is not in every instance constant, 

 they are lately more commonly placed in the 5th class, Peitfandria. 



2. The names of these orders have been translated, as follows ; 

 cequalis, equal ; fnperflua, superfluous ; frustranea, ineffectual ; 

 neccssaria, necessary ; segregata, separated. 



The orders of the 20th class, Gynandria, the 21st, 

 Monoecia, and the 22d, Dioecia, are distinguished by the 

 characters of some of the classes themselves which pre- 

 cede them, that is, almost entirely by the number of 

 the stamens, and have the same names, as MONAJVDRIA, 



DlANDRIA, &C. 



CXASS 23, Potygamia. 



This class has three orders, which are founded on 

 the situation of the stamen-bearing, pistil-bearing, and 

 perfect flowers. 



1. MONOECIA, lias eitherperfcct arid stemen-bearing, 

 or perfect and pistil-bearing flowers, or all these three 

 kinds on the same plant. 



2. DIOECIA, has the two or three kinds of flowers, on 

 two separate plants. 



3> TRIOECIA, has them on three separate plants* 

 The Fig, Ficus, is the only example- 



