54 NATURE STUDY 



another. This is cross fertilization. How is it accomplished ? 

 That is, how is the pollen carried from one flower to another ? 



In this the lupine may teach 

 a lesson. There are a great 

 number of species of lupines in 

 California. Any one of the 

 common forms will answer. 

 Where possible take the class 

 into a field where manv . ^if .rS- Ti^e flo.-er shown in Fig. 27 wUh 



both the parts shown in it removed. The 



lupines are in bloom. I^et P.a« showli here inclo.^es the stamens and pis- 



^ ^ til. When the bee ahg-hts on the platform of 



each one watch a group of J' "'^ f?'"' % '"• P"shed through it against 



o r the bee s body and a stream of pollen is 



lupines for visits of bees to the v^^^f^'^ ""^ of <b= point a. 

 plants he has under observa- 

 tion, and let him try to find out exactly what both bee 

 and flower do during the visit. The bees are in a hurrj' and what 

 they do is done so quickly, and what motions the plants make 

 are over in such a flash, that it is hard to make out at first what 

 has happened. But careful work will solve it. 



This is what can be seen: The bee hovers over the flower for an 

 instant, then alights on the little platform she finds there. Next 

 she thrusts her head down into a part of the plant after nectar. 

 She does not get any, as lupines do not furnish it. In this she is 

 deceived by its being like so many honey plants. While she thrusts 

 her head down into the flower, the part of the flower she is clinging 

 to is pressed down, and out of a point in the very front of it 

 a little stream of pollen oozes out on her body. As she gets no 

 honey she will usually take to gathering pollen. 



As the bee has probably visited many other flowers, her body 

 has already on it pollen from them. As she presses down the part 

 of the flower, not onh' the stream of pollen comes out of the small 

 hole, but the stigma of the pistil is also pushed up from this hole 

 against her body, and thus may get covered with the pollen from 

 flowers of other lupines. 



