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FERTILIZATION OF OPHRYS APIFERA. 

 By C. B. Clarke, M.A., F.L.S. 



Darwin ('British and Foreign Orchids,' p. 63) figures and 

 describes the fertiHzation of Ojjhrys ajyifera. He describes the 

 remarkably long, thin, and flexible caudicles of the pollinia, 

 necessarily curved forward at their upper ends. He continues, 

 *' The anther-cells naturally open soon after the flower is fully 

 expanded, and the thick ends of the pollinia fall out, the viscid 

 discs still remaining in their pouches "; and (on the next page, 65) 

 " we see that the anther-cells naturally open, and that the masses 

 of pollen, from their weight, slowly fall down." In the accom- 

 panying plate (fig. vii.) the very long caudicles are shown curved 

 after the pollinia have fallen out of the anther-cells, and sustaining 

 aloft (though themselves curved) the pollinia. Darwin appears to 

 have been somewhat surprised at these phenomena ; he adverts to 

 the slightness of the weight of the pollinia, and the remarkable 

 thinness of the caudicles. 



I picked last summer a 3-flowered spike of the Bee Orchis at 

 Box Hill ; in the low^est flower the pollinia had fallen on the lip ; 

 in the flower above, imperfectly expanded, the anther was curved 

 lower over the rostellum, but the two caudicles were out of the base 

 of the anther- cells and were drawn tightly straight across from the 

 rostellum (where they are firmly permanently attached) to the base 

 of the pollinia ; the appearance was as of the arched neck of a 

 horse pulled in tightly by a low hand. 



Subsequently, in the Savoy, I met with numerous many- 

 flowered spikes of the Bee Orchis ; and in the field I noticed that, 

 in the lowest flower with the pollinia still included in the anther- 

 cells, the caudicles were drawn out of the bases of the anther-cells 

 and quite straight. 



Later, some fresh spikes of the Bee Orchis were sent me by 

 Miss Loscombe h'om Andover, One detached opening flower I laid 

 on its side ; on raising carefully the sepal, the anther straightened 

 (as I imagine) imperceptibly ; the poUinia were drawn out by the 

 tension of the caudicles. In this position of the flower they could 

 not have fallen out by their own weight. It is, I need not say, 

 quite possible that I may in raising the sepal have disturbed the 

 anther -cell. 



Darwin appears to have examined very many flowers of Ojjhrys 

 apifera, in several localities, and during many seasons ; he also kept 

 living plants in his room, and observed the process of fertilization 

 day by day. It is therefore very improbable that such an observer 

 would be mistaken, even on the lesser points of the phenomena. 

 But unless the spontaneous opening of the anther-cells to allow the 

 pollinia to fall out by the action of gravity is a very rapid action, 

 I cannot understand how I saw nothing of it. My observations 

 were so scanty that I merely made a mental note of them, with the 

 intention of devoting a little more time to the points in question 



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