1923. Moffat — Study of Common Wild Flowers. 27 



and with it, in equal profusion, another plant that is cer- 

 tainly much liked by the males of every species of bumble- 

 bee — the Black Knapweed {Centaurea nigra). Generally, 

 in my neighbourhood, I found the Black Knapweed not 

 merely a favourite flower, but the favourite flower, of male 

 bumble-bees of most kinds. But in this field where the 

 Rest-harrow also occurred the bulk of the bees kept away 

 from the Knapweed, and kept on regularly passing from 

 flower to flower of the species that Miiller says they only 

 go to by mistake. I even saw one male Bombus agrorum 

 make what seemed to be a mistake — dart at a head of Knap- 

 weed (the colours of the two flowers being somewhat similar), 

 but turn away in disgust on finding that the flower it was 

 making for was only Knapweed and not the Rest-harrow. 



Now% I ask, is it credible that all these bees were 

 idiotically passing the long day in a continued vain search 

 for hone}/ in flowers that contained none, and in the midst 

 of a forest of flowers of another kind, which they knew 

 to contain honey exactly to their liking ? 



But we cannot say that the Rest-harrow^ does secrete 

 nectar till the nectar has been found. I am only pleading 

 for research into the subject. Readers of Darwin's " Fer- 

 tilisation of Orchids " are aware that for a long time many 

 of our common Orchises {maculata, Morio and pyramidalis 

 amongst others) were supposed to secrete no nectar, and 

 to be visited by bees only on a mistaken quest ; but it was 

 ultimately found that the bees knew well enough how to 

 get at the fluid they were in quest of by puncturing the 

 inner membrane of the nectary that contained it. If any 

 similar discovery has since been made about the Rest- 

 harrow I have never seen it mentioned. I can only say 

 that to me this plant is quite a conundrum. 



At any rate, I feel sure that inquiry into these and 

 similar questions cannot fail to be of interest, and to elicit 

 results that will give us an increased sense of the harmony 

 of nature. 



Dublin. 



