THE HIGHER DICOTYLEDONS. 357 



insects. The two stamens project horizontally and diverge a 

 little at each side ; the filament of each stamen has at its 

 base a small bend which forms a kind of hinge ; the style 

 hangs out over the lowest petal. A fly coming to the flower 

 first rubs its under side against the stigma, and then grasps 

 the stamens with its legs and draws them together to form a 

 support as it probes for honey in the corolla-tube, thus 

 causing the anthers to dust its body with pollen. When the 

 insect leaves, the stamens spring back to their former 

 position, and the flower can be visited several times. Do you 

 see why the corolla has no " platform " lower lip ? 



The sepals persist around the short flattened capsule and 

 grow a little longer after pollination. The ripe capsule, which 

 contains rather few seeds in each chamber, opens by two slits, 

 but the valves remain attached to the seed-bearing axis. The 

 seeds are thin, flat on one side and convex on the other ; they 

 escape gradually through the narrow slits; the sepals also 

 help in this censer-mechanism and prevent too many seeds 

 from falling out together except when a strong wind is 

 blowing. After flowering the racemes lengthen considerably ; 

 this aids in the dispersal of the seeds by wind (how ?) ; the 

 flower-stalks stand erect, close to the raceme axis, while the 

 flowers are young, spread out when the flowers open, and 

 become erect again when the flowers have been pollinated. 



360. The Foxglove Family {Scrophulariaceae) shows a 

 fairly wide range of flower structure, as we have seen from 

 our study of Foxglove and the Speedwells, but all agree in 

 having the flower zygomorphic (in some cases nearly regular), 

 with gamosepalous calyx (sometimes almost polysepalous), 

 a gamosepalous and typically two-lipped corolla; stamens 

 generally in two pairs, epipetalous ; a honey-disc at base of 

 ovary ; a two -chambered ovary (chambers in vertical plane of 

 flower) with numerous ovules (few in Veronica) on axile 

 placentas. 



361. Flower Mechanisms in Scrophulariaceae. The 

 flowers of most Scrophulariaceae are adapted for pollination 

 by bees, though the short-tubed open flowers of Veronica 

 and Verbascum are visited chiefly by flies. In most cases the 

 entering bee rubs the anthers and style with its upper side, 



