X 
THE LINNiEAN 
Class 12.— Icosandria , contains all flowers with 20 or 
more stamens standing on the calyx or flower-cup ; this is 
the outer whorl or sheath of the flower. 
Class 13.— Polyandria, flowers having 20 or more sta¬ 
mens not attached to the flower-cup. 
Class 14.— Didynamia, 4 stamens, 2 long and 2 short. 
Class 15.— Tetradynamia, 6 stamens, 4 of them longer 
than the other two. 
Class 16.— MonadeVplda, stamens united by the fila¬ 
ments of the stamens in the one set, 
Class 17.— Diadelphia, stamens united by their fila¬ 
ments in two sets. 
Class 18 ,—Polyadel/pTiia, stamens united by their fila¬ 
ments into three or more sets. 
Class 19.— Syngenesia, stamens united by their anthers 
in one set, the flowers compound. 
Class 20. — Gynandria, in which the stamens are united 
to the pistil. 
Class 21.— Moncecia, stamens and pistils in separate 
flowers in the same plant. 
Class 22.— Dicecia, stamens and pistils in separate 
plants. 
Class 23.— Polygcmia, stamens variously situated, 
sometimes in flowers with pistils, sometimes stamens 
only. 
Class 24.— Cryptogamia, the flowers invisible to the 
naked eye, as in lichens and mosses. 
