THE FLOWER AND THE BEE 



to the scarlet runner, or from the goldenrod to the purple 

 vervain {Verbena hastata). 



On the other hand, the honey-bee often displays a remark- 

 able power of distinguishing between closely allied species even 

 when they are of the same color. One of the common golden- 

 rods {Solidago graminifolia) has its heads or capitula arranged' in 

 crowded, flat-topped corymbs. (Fig. 47.) Another common 

 variety (S. rugosa) has the inflorescence panicled. (Fig. 48.) 

 In an upland pasture these two species were found growing to- 

 gether, the panicled form being much the more abundant. 

 Honey-bees, the only insects present, showed a marked pref- 

 erence for 8. graminifolia, although occasionally they passed 

 over to the other species. They were repeatedly seen to leave 

 S. graminifolia, and after flying about, but not resting on the 

 flowers of S. rugosa, return to the plants they had left only a 

 few moments before. In another instance a bee was seen to 

 wind its way among the plants of the latter species until it 

 found an isolated plant of S. graminifolia. A plant of each 

 of the above species was bent over so that the blossoms were 

 intermingled, appearing as a single cluster; a honey-bee rested 

 on 8. graminifolia, and it seemed very probable that it would 

 pass over to the flowers of S. rugosa, but such was not the case, 

 for presently it flew away to another plant of the former. The 

 behavior of these bees in their endeavors to adhere to a single 

 species was thus attended both by loss of time and repeated 

 visits to the same blossoms. 



On another occasion the whitish or cream-colored inflores- 

 cence of Solidago bicolor, our one non-yellow species of golden- 

 rod (Fig. 49), was observed to be very frequently visited by the 

 males of Bombus ternarius, while the yellow-flowered golden- 

 rods in the vicinity were entirely neglected. By holding yel- 

 low-flowered clusters directly in their way I repeatedly in- 



