The Discoveries of Four Great "Botanists 



Fig. 



Sprengel pointed out that in many flowers the 

 stamens were far below the stigma, as shown in C, 

 Fig. 2 and in Fig. 4. How, then, 

 could the pollen reach the stigma? 

 Clearly not in the manner sug- 

 gested by Grew and Linnaeus. 



Sprengel partially solved this 

 mystery. He cast a ray of light 

 into the darkness, but it was 

 not stronof enouirh to reveal the whole truth. 



He announced the startling theory that : 



I. Flowers, which, from their structure, are un- 

 able to fertilize themselves, are fertilized by insects. 



n. That all such flowers contain nectar, which 

 is food for insects, and that, in obtaining this food, 

 the insects brush the pollen from the anthers with 

 the hairy parts of their bodies. As they fly away, 

 they necessarily come in contact with the stigma, 

 which scrapes off the pollen they have just collected 

 and is thus fertilized. D, Fig. 2, represents the 

 process suggested. 



This theory, he claimed, would explain also the 

 presence of color and fragrance * — both of these 

 attributes serving to attract insects, the color also 



*No sooner was this fact asserted than it was urged that certain 

 flowers, which Sprengel afterward called '' Shein saft bhtmen,'' or 

 sham-nectar producers, of which the Orchis tnorio is a good 



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