f 



ELEMENTS OF STRUCTURAL BOTANY. 29 



before the sepals, but before the spaces between them. 

 In the Pea- blossom this rule holds good if the large 

 petal is considered as one, but not otherwise. Again, 

 the veiuiug of this petal is similar to that of a common 

 leaf, there being a central rib from which the veins 

 spring on each side ; and lastly, there are some flowers 

 of the Pea kind — Cassia, for example — in which this 

 particular petal is of nearly the same size and shape as 

 the other four. 



39. Great ^A(^illow-herb. This plant is extremely 

 common in low grounds and newly cleared laud, and 

 you may easily recognize it by its tall stem and bright 

 purple flowers. 



Observe the position of the flowers. In the three 

 plants first examined we found the flowers at the end 

 of the stem. In the Willow-herb, as in the MaUow, 

 they spring from the sides of the stem, and immedi- 

 ately below the point from which each flower springs 

 you will find a small leaf or bract 

 (Fig. 40.) Flowers which arise 

 from the axils of bracts are said to 

 be axilhirt/, whilst those which are 

 at the ends of stems are called ter- 

 minal, and you may remember 

 that flowers can only be produced 

 in the axils of leaves and at the 

 ends of stems and branches. ^>g- ^^^ 



40. Coming to the flower itself, direct your attention, 

 first of all, to the position of the ovary. You will find 

 it apparently under the flower, in the foi'm of a tube 

 tinged with purple. It is not in reality under the 

 flower, because its purplish covering is the calyx, or 



