1885.] FERTILIZATION OF BRITISH ORCHIDS. 507 



attacked witli very severe fever, and, after stopping several days to 

 rest, I found myself obliged to return to the ship, and was then 

 invalided home as my only chance. Dr. Kummel has returned 

 with instruments to take proper measurements of the current, and 

 to satisfy himself as to a number of points. In the meantime, I 

 take home a preliminary memoir, pieces of the wood and core, etc., 

 and seeds whicli we were fortunate enough to obtain. I am sorry I 

 cannot show you them, as they are in my boxes on the steamer. 

 The chemist on board says the black substance is a very pure 

 amorphous carbon, giving hardly a trace of ash. Dr. Kummel is 

 much puzzled to account for the existence of this singular tree 

 by any process of natural selection. He says he cannot see how 

 the possession of this system of electric currents could have 

 benefited it. It has certainly, hov/ever, cleared out nearly every 

 other species of forest tree from its habitat. Yes, I sincerely hope 

 Elsassia elcctrica will grow in other countries ; it would be a 

 great thing, would it not ? ' " 



FERTILIZATION OF BRITISH ORCHIDS. 



BY A. D, WEBSTER, F.B.S.E. 



IN the whole vegetable kingdom there is perhaps no order of plants 

 the structure of whose flowers is so anomalous as regards the 

 relation borne to each other by the parts of reproduction as the 

 Orchidacea?. The necessity of insect agency in the fertilization of 

 these plants, although long hidden in obscurity, is now well known, 

 and the many v/onderful and beautiful contrivances, as well as 

 endless diversity of structure for the furtherance of this object, are 

 so full of interest even to the general observer, that we may be 

 excused for devoting, in conjunction with the preceding notes on 

 our native orchids, a chapter to the subject. That cross-fertilization 

 is beneficial to most orchids, indeed of the highest importance, may 

 be inferred from the almost innumerable structures serving for this 

 purpose which they present. Of the forty species of British orchids 

 just described, all, with perhaps two exceptions — Oplirys ainfera and 

 Neotinca or Orchis intacta — are entirely dependent on insect agency 

 for their fertilization and the perpetuation of their race ; while three 

 others — Ncottia nidus-avis, Fpipactis latifolia, and Ccphalanthera. 

 grandifiora — although occasionally fertilized by insects, are also, though 

 more or less in an incomplete manner, capable of self-fertilization, so 

 that even if not visited by insects, a fair proportion of seed-bearing 



