244 



THE FLOWER. 



rically opposite, and its section is sometimes indicated by a dot or 

 small circle. In an axillary tetramerous flower one of the sepals 

 will be anterior, one posterior, and two lateral, or right and left; 

 as in the annexed diagram of a Cruciferous blossom (Fig. 280) ; 



while the petals, alternating with the sepals, occupy intermediate 

 positions, or consist of an anterior and a posterior pair ; while the 

 stamens, again, correspond to the sepals in position. A pentame- 

 rous axillary flower, having an odd number of parts, will have 

 either one sepal superior or posterior and two inferior or anterior 

 (as in Rhus, Fig. 281), or else, vice versa, with one inferior and 

 two superior, as in papilionaceous flowers (Fig. 282) : in both cases 

 the two remaining sepals are lateral. The petals will consequently 

 stand one superior, two inferior, and two lateral, in the last-named 

 case (Fig. 282), and one inferior, two superior, and two lateral, in 

 the former (Fig. 281). In terminal flowers (401), the position of 

 parts in respect to the uppermost leaves or bracts should be noted. 



SECT. IV. THE VARIOUS MODIFICATIONS OF THE FLOWER. 



445. The complete and symmetrical flowers, with all their or- 

 gans in the most normal state, that have now been considered, will 

 serve as the type or pattern, with which we may compare the 

 almost numberless variety of forms which blossoms exhibit, and 

 note the character of the differences observed. We proceed upon 

 the supposition that all flowers are formed upon one comprehen- 

 sive plan, a plan essentially consonant with that of the stem or 



FIG. 280. Diagram of a Cruciferous flower (Erysimum) ; a, the axis of inflorescence. (The 

 bract is abortive in this, as in most plants of this family.) 



FIG. 231. Diagram of the flower of a Rhus, with the axis, a, and the bract, b, to show the 

 relative position of parts. 



FIG. 282. Diagram of a flower of the Pulse tribe, with a, the axis, and b, the bract. 



