280 



THE FLOWER. 



with seven, heptandrous ; with eiglit, octandroiLS ; with nine, ennean- 

 drous ; with ten, decandrous ; with twelve, dodecandrous. "When 

 more than twelve, and inserted on the calyx, they are isocandrous, or 

 when inserted on the receptacle, poli/androus. 



518. As to their union with each other, this may take place in 

 various ways. Sometimes the filaments are comhined, while the 

 anthers are distinct. When thus united hy their filaments into one 

 set, they are said to be monadelphous ; as in the Lupine, &.Q. (Fig. 



462) and Mallow. 

 "When united by their 

 filaments into two 

 sets, they are diadel- 

 phous, as in most 

 plants of the Pulse 

 family, where nine 

 stamens form one set 

 and the tenth is soli- 

 tary (Fig. 4G1) ; and 

 in Dicentra (Fig. 369 - 371), where the six stamens are equally com- 

 bined in two sets. "When united or ar- 

 ranged in three sets or parcels, they are 

 said to be tinadelphous, as in the com- 

 mon St. Johnswort ; or if in several, 

 polyadelphous ; as in Linden. When 

 stamens are united by their anthers into 

 a tube or ring, they are said to be syn- 

 genesious (Fig. 463, 464). This occurs 

 in the Avhole vast order of Compositje. 

 Here the five filaments are distinct ; 

 Avhereas in Lobelia, and also in the 

 Melon and Gourd (Fig. 465, 466), both 

 the filaments and the anthers are united ; that is, the stamens are 

 monadelphous as Avell as syngenesious. 



519. As to insertion, stamens are hypogynous (466) when borne 

 on the receptacle, that is, when not adnate to any other organ ; 



FIG. 461. Diadelphous stamens (3 and 1) of a Pea. 462. Monadelphous stamens of a 

 Lupine. 



FIG. 4G3. Five syngenesious stamens of a Composita. 464. The same, laid open. 



FIG. 485. Column of stamens, at once triadelphous and syngenesious, of the Gourd : the 

 floral envelopes cut away. 466. A cross-section of the united anthers, nearly the natural size. 

 467. A sinuous anther of the Melon. 



