HA RD WICKE'S SCIENCE- G OS SIP. 



241 



THE RED LEAF AGAIN: A REPLY. 



By G. W. Bulman, M.A. 



{Continued from page 232.] 



WILL now examine 

 briefly the state- 

 ments brought for- 

 ward from the 

 authorities against 

 my views. On the 

 whole, I cannot 

 see that they affect 

 my arguments at 

 all — except, in- 

 deed, to strengthen 

 them. 



I instanced the 

 common scarlet 

 poppy, and the 

 two periwinkles as 

 very conspicuous 

 red and blue 

 flowers upon 

 which I had never, 

 or scarcely ever, 

 observed bees. Mr. Tansley cites Hermann Muller 

 to show that the former is visited by seven species of 

 bees, the smaller periwinkle by the same number, 

 and the larger periwinkle by one. I willingly accept 

 these statements as facts. At the same time, I must 

 put in the caution, that such statements as to the 

 number of species of bees which have been noted 

 as visiting particular flowers is apt to be misleading, 

 if not carefully considered. 



It is not the number of species visiting a flower, 

 but the absolute number of blossoms visited, and 

 thus receiving the benefits of cross-fertilisation which 

 is important ; the flower receiving the visits of only 

 one species of bee may, in the long run, have a 

 larger number of blossoms cross-fertilised than the 

 one receiving the visits of seven. For example, I 

 have compared the visits of bees to the white flowers 

 of the duckweed and to the blue of a common speed- 

 well ( Veronica Buxbaiimii), 



In the garden where I made the observation, the 

 No. 287.— November iSSS. 



former was growing thickly, with the latter scattered 

 plentifully among it, and elsewhere. Speaking 

 roughly, about one hundred chickweed flowers were 

 visited for every one of the veronica : yet, during the 

 period of observation, the former attracted two 

 species of bee, and the latter three. 



This fact also speaks not undecidedly on the 

 subject of the bee's asserted preference for blue. Is 

 it not strange, on the supposition of its truth, that 

 the white flowers should receive more visits than the 

 blue ? On a rough calculation a bee visited about 

 twenty chickweed flowers per minute : a score of 

 bees at this rate would visit every blossom in the 

 garden in the course of a spring day. And if, in a 

 race of white flowers, practically every flower gets 

 the benefit of a bee's visit, where is the advantage 

 which those happening to have a tinge of yellow, 

 red, or blue are supposed to obtain ? It becomes a 

 vanishing quantity : the uncoloured ones are equally 

 benefited. 



To return to the poppy and periwinkles, I must 

 confess that the general impression derived from my 

 observations remains the same. If, during an ex- 

 tended series of observations, many thousands of bees 

 are seen on greenish, white and yellow flowers, and 

 none or very few on such conspicuously blue and red 

 ones as the above, I do, and must, draw the conclusion, 

 that bees have no decided preference for red and blue 

 flowers. I do not infer, and do not wish any one to 

 infer from the fact, that I have never seen a bee on a 

 particular flower, that therefore it is not visited : 

 it is the comparative number of visits which is the 

 point. 



The habits of bees with regard to those blue 

 flowers which have white and ether varieties is 

 decisive as to their taste in the matter of colour. 



I have noticed them on the flowers of the forget- 

 me-not, where blue and white varieties grew together : 

 they pass with seeming indifference from blue to 

 white, and from white to blue. 



Among garden hyacinths, where blue, pink, and 



M 



