THE FLOWER AND THE BEE 



The bright-yellow staminate aments of the pussy-willow 

 {Salix discolor) (Fig. 55) are great favorites of vernal species 

 of Andrena, whence Smith calls them "harbingers of spring." 

 The pussy-willows bloom in northern New England during the 

 latter part of April, and their bright-yellow aments are very 

 pleasing objects in the cold, gray landscape. They are very 

 attractive to a varied company of insects, as honey-bees, bum- 

 blebees, flies, butterflies, and beetles. It is a busy scene and 

 one which the naturalist can never tire of watching; but it is 

 not one of unmixed happiness, for little tragedies take place 

 before our eyes. Among those which come to sip the nectar 

 are little dance-flies (Empididcp), and not infrequently they 

 are seized and carried away bodily by black robber-ants which 

 roam everywhere. Honey-bees and many species of Andrena 

 come in great numbers to procure pollen for brood-rearing. A 

 part of the andrenid bees gather only a portion of the pollen 

 they require from the willows and the balance from the maples, 

 plums, cornels, and Viburnums; but there are four species 

 {A. illinoiensis, A. iiiaricB, A. erythrog aster, and A. moesta), 

 which get their whole supply from this genus of plants. Of 

 the autumnal flying species of Andrena there are five {A. cana- 

 densis, A. nubecula, A. solidaginis, A. hirticincta, and A. asteris), 

 which I have collected only on the flowers of the Compositce, or 

 aster family; and four of these bees confine their visits very 

 largely to the goldenrods. In both Salix and Solidago the in- 

 florescence offers an ample supply of nectar and pollen, and 

 there is little temptation for andrenid bees to go elsewhere, 

 when their time of flight coincides with the period of blooming 

 of these two genera. 



But in other localities Andrena erigenioe is reported to be a 

 monotropic visitor of the spring-beauty {Claytonia virginica), 

 and Andrena violce of the violet (Viola cucullata), Andrena 



110 



