416 NINETEENTH CENTURY. FT. in. 



in Brandenburg, but he became so wrapt up in his botanical 

 studies that he was obliged to give up his office, and he 

 lived in great poverty at Berlin, teaching languages and 

 botany. He was so poor that he was not able to publish 

 the second volume of his famous work on botany, and the 

 publisher had not even given him a copy of the first volume 

 for his own use. Sprengel tells us that in the summer of 

 1767 he noticed that in the flower of the Geranium sylvati- 

 cum the fine little glands containing honey at the base of 

 the petals are protected by thick hairs, so that the rain and 

 dew cannot reach them, just as our eyes are protected by 

 our eyebrows and eyelashes from drops of perspiration creep- 

 ing down the face ; at the same time he observed that 

 insects had no difficulty in passing through the hairs and 

 sucking out the honey. 



Again, he found that in the forget-me-not, the line of little 

 spots in the corolla points directly to the place where the 

 insects must go to get the nectar at the base of the flower. 

 This proved, he thought, that there are special provisions in 

 flowers to keep the honey for the insects, and to guide them 

 to it. So far the flower was of use to the insect ; the next 

 point he discovered was that the insect in its turn benefits 

 the flower. He observed that the Willow Epilobium, or 

 Rose-bay, though it has its stamens and its seed-vessel both 

 in one flower, cannot use the pollen from the stamens to 

 fertilise the ovules in the seed-vessel, because the stamens 

 have withered away and their pollen is gone, before the 

 stigma or top of the seed-vessel is sticky and ready to 

 receive it. How then do the seeds become fertilised ? 

 Sprengel watched carefully, and found that insects, in flying 

 from flower to flower, brought the pollen-dust clinging to 

 them from younger flowers in which the stamens were just 

 ripe, and left it in the older flowers where the stigma was 



