On Flowers and Insects. 1 1 5 



petals ; thirdly, of one or more stamens, consisting 

 of a stalk or filament > and a head or anther, in 

 which the pollen is produced ; and fourthly, a pistil, 

 which is situated in the centre of the flower, and 

 consists generally of three principal parts : one or 

 more compartments at the base, each containing one 

 or more seeds ; the stalk or style ; and the stigma, 

 which in many familiar instances forms a small 

 head at the top of the style or ovary, and to which 

 the pollen must find its way in order to fertilise 

 the flower. 



3. At the close of the last century, Conrad 

 Sprengel, a German schoolmaster, published a valu- 

 able work on flowers, in which he pointed out that 

 the forms and colours, the scent, honey, and general 

 structure of flowers, have reference to the visits of 

 insects, which are of importance in transferring the 

 pollen from the stamens to the pistil. This admir- 

 able work, however, did not attract the attention it 

 deserved, and remained almost unknown until 

 Mr. Darwin devoted himself to the subject. Our 

 illustrious countryman was the first clearly to per- 

 ceive that the essential service which insects perform 

 to flowers, consists not only in transferring the 

 pollen from the stamens to the pistil, but in trans- 

 ferring it from the stamens of one flower to the 

 pistil of another. Sprengel had indeed observed 

 in more than one instance that this was the case, 

 but he did not altogether appreciate the importance 

 of the fact. 



I 2 



