LUPINE, ALFALFA AND BUR-CLOVER 



places year after year without cultivation. The flowers 

 of the alfalfa, too, have their special mechanical trick. 

 Examine a cluster of flowers carefully, looking each flower 

 squarely in the face. Perhaps you will find that some 

 flowers, like the enlarged one in the picture, have the 

 column of stamens and pistil close against the banner, 

 while in other flowers nothing of the sort is there. Take 

 one of these latter flowers, and imagine where an insect 

 seeking honey would thrust its tongue; imitate this 

 action by inserting a needle, and instantly, the stamens 

 and pistil fly up like a "jack-in-the-box." Now let us look 

 for this machinery. Remove the calyx and banner, and 

 push back the column of stamens and pistil into the keel. 

 You will see that there are two little projections, one 

 frcTm each wing, that are fitted over this column, also 

 that the wings are firmly fastened to the keel by means 

 of other projections that fit into pockets. So the column 

 was at first held down in the keel by means of these pro- 

 jections from the wings. The honey is at the very base of 

 the stamens, and is reached only through two little open- 

 ings on the upper side. When an insect alights on the lower 

 part of the flower, and thrusts his tongue directly in for 

 honey, as you did the needle, the tongue separates the pro- 

 jections, and the stamens and pistil fly up with much 

 force and strike the tongue. The pistil is likely to strike 

 first, and the whole tongue becomes newly dusted with 

 pollen. 



Of course this is a very rude way for the flower to 

 treat its guest. The blow must be disagreeable, and the 

 bees and butterflies seem to dislike it, for some of them 

 have learned to get honey by inserting the tongue at the 

 base and side of the flower ; in this way they obtain honey 

 without touching the stigma or pollen, and the flower, on 

 account of its rude behavior, gets no help from the guest. 

 Indeed, while the'alfalfa has a very ingenious mechanism, 



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