124 INTRODUCTION 
beetles that penetrated into the flowers, or long-tongued flies (Bombylius, Rhingia, 
Empis) or humble-bees which managed to reach the nectar, or thievish humble-bees 
that broke in and carried away the spoil. It is only in a few Lepidopterid Flowers, 
continues Miiller, that the booty is materially diminished by these intruders. This 
is the case, however, in Gentiana verna, Silene nutans and inflata, where it is due 
to the incursions of humble-bees, and it is particularly so in Rhinanthus alpinus, 
which is rendered useless to humble-bees by the Lepidoptera. 
Hermann Miiller (Kosmos, iii, 1878, pp. 417 and 418) called attention to 
a most remarkable relation between the coloration of Butterfly Flowers and that of 
Fic. 36. A. Lychnis Flos-cucul?, in which the nectar is secured by long-tongued bees and hover-flies, 
as well as by Lepidoptera. B. Lychnzs Flos-Jovis, in which the honey is secured only by Lepidoptera. 
C.D. Daphne Mezereum, visited by Lepidoptera, Bees, and Flies. E.F. Daphne striata, visited only by 
Lepidoptera. (After Herm. Miiler.) 
their lepidopterous guests. ‘It is certainly not purely accidental,’ says Miiller, ‘that 
most of the butterflies of the Alps, the commonest floral guests in that region, are 
vivid red in colour (numerous species of Argynnis and Melitaea, and several of 
Polyommatus and Vanessa), and that bright red flowers are visited with marked 
preference by such butterflies.’ Miller noticed, for example, that the flowers of 
Lilium bulbiferum were exclusively visited by the fiery-red species Argynnis Aglaja, 
Polyommatus Virgaureae, and P. hippothoé var. eurybia, these insects being such 
frequent visitors that several of them often settled at once on the same flower, to 
which their similarity in colour at the same time afforded them the protection of 
invisibility. I may add, as a further example, that the Brimstone Butterfly (Rhodo- 
cera Rhamni), which is the commonest visitor and pollinator of Primula acaulis, has 
precisely the same colour as the flower it visits. 
