ARTIFICIAL CLASSES. 195 



In the view we are now to take of the classes and orders of 

 Linnaeus, our attention will not, as in the Natural Method, be 

 given to families of plants, but to genera. We shall consider 

 each class separately, with the orders it contains, and the most 

 remarkable genera under each order ; we shall, in some cases, 

 refer these genera to their 'natural families; but it has been 

 before remarked, that the artificial system in some cases sepa- 

 rates these families. 



The Classes in the artificial system are 21. 



Groups of Classes. 



1st. The first ten classes are founded upon the number of stamens. 



2d. Eleventh and Twelfth upon the number and insertion of stamens. 



3d. Thirteenth and Fourteenth, upon number and length of stamens. ' 



4th. Fifteenth, Sixteenth, Seventeenth and Eighteenth, upon connexion of 

 stamens. 



5th. Nineteenih&n& Twentieth, upon position of stamens. 



The Twenty-first class includes all plants which either have not stamens and 

 pistils, or in which these organs are too minute to be seen, without the help of 

 of a microscope. 



The orders are founded, 



1st. Upon the number of Pistils. 



2d. Upon the seeds being covered, or lying uncovered in the calyx. 

 3d. The relative length of the pods. 



4th. The comparison between the disk and ray florets of compound flowers. 

 5th. Number of stamens. 



6th. The orders of the class Cryptogamia are distinguished by natural family 

 characters. 



NAMES OP THE ARTIFICIAL CLASSES. 



1. MONANDRIA, one stamen. 



2. DIANDRIA, two stamens. 



3. TRIANDRIA, three stamens. 



4. TETRANDRIA, four stamens. 



5. PENTANDRIA, five stamens. 



6. HEXA-NDRIA, six stamens. 



7. HEPTANDRIA, seven stamens. 



8. OCTANDRIA, eight stamens. 



9. ENNEANDRIA, nine stamens. 



10. DECANDRIA, ten stamens, 



11. ICOSANDRIA, over ten slamens, situated on the calyx. 



12. POLYANDRIA, over ten stamens situated on the receptacle. 



13. DIDYNAMIA, four stamens, two long and two short, flowers labiate. 



14. TETRADYNAMIA, six stamens, four long and two short, flowers cruciform. 



15. MONADELPHI A, stamens united by their filaments into one set. 



16. DIADELPHIA, stamens united by their filaments into two sets, flowers 

 papilionaceous. 



17. SYNGENESIA, five stamens united by their anthers, flowers compound. 



18. GYNANDRIA, stamens growing on the pistil. 



19. MoN(EciA, stamens and pistils on different flowers of the same plant. 



20. DIGECIA, stamens and pistils on different flowers of different plants. 



21. CRYPTOGAMIA, stamens and pistils invisible. 



Artificial classes considered in groirps Circumstances on which the orders 

 are founded Names of the artificial classes. % 



