1902 Marsh Botany in Spring 129 



more fascinating than Darwin's ' On the various Contriv- 

 ances b}^ which British and Foreign Orchids are fertihzed 

 by Insects.' From this work we learn that orchids pos- 

 sessing long spurs or nectaries are fertilized by lepidoptera, 

 those with short nectaries by bees, wasps, and flies. This 

 subject is too wide to be treated of in these notes; but for 

 the instruction and amusement of young botanists I will 

 quote a passage from Mr E. Step's ' Wayside and Woodland 

 Blossoms,' in which the author briefly indicates how the 

 processes of fertilization may be made clear by a simple 

 experiment. He tells his readers to take a finely-pointed 

 pencil to represent the head and tongue of a bee in search 

 of nectar. " We push the point gently down the spur [of 

 the orchid], when a part of the pencil touches against the 

 rostellum and presses it down, touches lightly the viscid 

 feet of the pollen masses (pollinia), and as the pencil is 

 withdrawn both come with it, and stick out from it like a 

 pair of horns. Be careful to hold the pencil in the exact 

 position it now occupies, and watch. The heavy heads of 

 the pollinia are drooping forward, but after a few minutes 

 they cease to fall lower. Now push the pencil into this 

 other flower. The pollen masses go directly to the stigma, 

 and some of the pollen is detached. If you are watching 

 where orchids grow it is no uncommon thing to see insects 

 flying round with these pollinia attached to their heads or 

 tongues like a pair of horns. It will be seen to be impos- 

 sible for the pollen to fall upon the stigma of the same 

 flower, and from its elastic attachments it is impossible 

 that it should be carried by the wind to another flower, 

 so that insect agency is here an absolute necessity." This 

 experiment may be tried with 0. mascula, morio, macidata, 

 or latifolia. 



The bogbean or buckbean {Menyanthes trifoliata), one of 

 the loveliest of our marsh flowers, — indeed, of our British 

 wild-flowers, — begins to bloom in May. The more boggy 

 the marsh the more likely it is to contain this exquisite 

 flower — in fact, I have seen it growing in a dyke, where 

 its trifoliate leaves were entirely submerged and its beautiful 

 spike of pink-and-white flowers rose from the water like the 

 whorled spike of the water-violet. The day when I first 



