176 MB. C. DAEWIN OS" THE SEXUAL KELATIOyS OP 



sides, to that side where the structure of the flowers allows the 

 easiest access to it, as in Lyihrum, Papilionaceous flowers, and 

 many others. The rule consequently is that when the pistil and 

 stamens are bent, the stigma and anthers are brought into the 

 pathway towards the nectary. There are a few cases which seein 

 to be exceptions, but they are not so in truth : for instance, in the 

 Grloriosa lily, the stigma of the grotesque and rectangularly bent 

 pistil is brought, not into the pathway from the open air towards 

 the nectar-secreting recesses of the flower, but into the circular 

 route from one nectajpy to the other ; in Scrophularia aquatica 

 the pistil is bent downwards from the mouth of the flower, but 

 it thus strikes the pollen-dusted breasts of the wasps which 

 habitually visit these iU-scented blooms. In the above rule we see 

 one more instance of the supreme dominating power of insects 

 over all the minor structural details of flowers, especially of those 

 which have irregular corollas. Elowers which are fertilized by 

 the wind must of course be excepted, but I do not know of a 

 single instance of an irregular flower which is fertilized or crossed 

 by this means. 



I have delayed too long on these points, but I must allude to 

 one other. We have seen that the three pistils of different 

 lengths have each two half-dozen sets of stamens of correspond- 

 ing length. When bees suck the flowers, the longest stamens, 

 bearing the green pollen, rub against the abdomen and the iate- 

 rior sides of the posterior legs, as does likewise the stigma of the 

 long-styled form. The stamens of middle length and the stigma 

 of the mid-styled form rub against the under side of the thorax 

 and between the front pair of legs. The shortest stamens and 

 the stigma of the short-styled form must rub against the pro- 

 boscis and chin ; for the bees in sucking insert only the front of 

 their heads into the calyx. On catching bees, I observed much 

 green poUen on the inner sides of the hind legs and on the abdo- 

 men, and much yellow poUen on the under side of the thorax. 

 There was also pollen on the chin, and, it may be piresumed, on 

 the proboscis, but this was difficult to observe. I had, however, 

 independent proof that pollen is carried on the proboscis ; for in 

 a protected short-styled plant (which produced only two cap- 

 sules) one small branch was accidentally left during many days 

 pressing against the iine net, and bees were seen inserting their 

 probosces through the meshes, and in consequence numerous 

 capsules were formed on this one small branch. From these 

 several fects it foUows that insecta would chiefly carry to the 



