THE FLOWER AND THE BEE 



landing-stage would be in the way, the lobes of the petals are 

 turned backward. By the second evening the corolla has 

 changed within from white to yellow, the stamens have bent 

 downward, while the stigma has moved upward and now 

 stands in front of the entrance. The flowers are also occa- 

 sionally visited by bumblebees, which are able to reach a part 

 of the nectar. Very likely the honeysuckle was once a bumble- 

 bee flower, but the corolla-tube has lengthened to such an ex- 

 tent in response to the visits of moths that the bumblebees are 

 at present nearly excluded. The flowers are frequently visited 

 by humming-birds in the daytime. 



The yellow evening-primrose (CEnothera biennis), so common 

 in hedgerows and waste land, is also pollinated by hawk-moths, 

 but in this locality they are not frequent visitors. The flowers 

 expand so quickly at about dusk that the motion of the petals 

 is clearly visible. The anthers are open and are covered with 

 pollen, but the four lobes of the stigma are folded close together. 

 The day following the anthers shrivel and the four stigmatic 

 lobes diverge, forming a cross, which a hawk-moth cannot fail 

 to touch. However it may have been in the past, the flowers 

 at the present time do not appear to attract a sufficient number 

 of visitors, for according to the observations of De Vries in 

 Europe and of Davis in America they are regularly pollinated 

 in the bud. (Fig. 70.) 



Close by the evening-primrose I often find the night-flowering 

 catchfly (Silene noctiflora), called catchfly because the whole 

 plant is viscid, hairy, and destructive to many small flies. The 

 small white flowers open at sundown, but I have found them 

 very sparingly visited by moths. (Figs. 71, 72, and 73.) 



Of the other moth-flowers only a few of the more common 

 can be mentioned here; they are characterized by having white 

 or nearly white flowers which open in the evening, have long 



150 



