55 



either to the right or to the left, holding the stamens in such 

 a position that it touches the bee upon the side; the flower is 

 therefore an example of what Delpino calls a pleuYotribe 

 flower. Ten lone black anthers with terminal pores turn in 

 an opposite direction from the pistil. The petals are bright 

 yellow, the upper ones are provided witii a little red at base 

 which serves as a pathfinder, but not as a nectar guide, since 

 nectar is wanting. All are widely expanded and flexible ex- 

 cept the lateral one toward which the anthers turn, which is 

 erect and strongly incurved and so stiff that it commonly 

 breaks on being bent back." 



"The flowers are visited exclusively by bumble bees, 

 females and workers in search of pollen. Landing upon the 

 anthers they seize them between their mandibles and stroke 

 them downwards with a sort of a milking motion. The pol- 

 len being thus forced out of the terminal anther-pores, falls 

 either directly upon the bee or upon the lateral petal which 

 is pressed close against the bee's side. In this way. the side 

 of the bee which is next to the incurved petal receives the 

 most pollen. Both right and left-hand flowers are found 

 upon the same plant. A bee visiting a left-hand flower re- 

 ceives pollen upon the right side and then flying to a right- 

 hand flower, strikes the same side against the stigma." 



The plants of this order are adapted to short- 

 tongued insects; then too, the large number of 

 stamens causes it to be sought by a numerous class of Dip- 

 tera and Hymenoptera. The nectar is secreted by the wall of 

 the tube of the receptacle. The amount of this secretion 

 varies, in some cases no nectar is secreted. Some of the 

 species are delightfully fragrant, others are without any 

 odor. 



Native Plum. A conspicuous plant in woods, sometimes 



