754 Humble Bee and Pollination of Red Clover, [jan., 



herself. More eggs are subsequently laid, and the nest and 

 cells are added to during the summer as occasion requires, 

 but the inmates of the nest consist of the queen and numerous 

 workers only. The cells left empty as the workers issue from 

 the cocoons are utilised as receptacles in which honey is 

 stored, to serve as food for the young grubs during wet or 

 unfavourable weather when the workers are detained inside. 

 Later in the season males and females are reared as well as 

 workers (which are neuters or abortive females), and even- 

 tually fertilisation of the females takes place, and the cycle 

 described above is repeated. 



Pollination of Red Clover. — An enquiry has been addressed 

 to the Board with regard to the value of these insects for the 

 purpose of fertilising red clover, and on this point it may 

 be remarked that the honey in the red clover flower is 

 secreted at the base of the stamens, and lies at the bottom of 

 a tube 9 to 10 mm. long. In order to reach this honey by 

 the usual means an insect must have a proboscis of the same 

 length. The stamens which produce the pollen, and the 

 stigma of the style which receives the pollen, are covered 

 over by parts of the red clover flower, known as the keel or 

 carina, while another portion of the red clover flower, known 

 as the wings, is also concerned in the process. 



The Humble Bee, on visiting a red clover flower, holds on 

 to the petals (wings) with its forelegs, and these petals and 

 the keel are pulled in such a way that the anthers of 

 the stamens and the stigma protrude. As the style 

 is taller than the stamens, the stigma first comes in 

 contact with the bee's head and receives any pollen 

 present on the underside of the head of the visiting bee. 

 The stigma is thus cross-pollinated. The anthers of the 

 stamens next strike the bee's head and dust their pollen 

 on to the bee. The bee, dusted afresh with pollen, visits a 

 second red clover flower, and the process is repeated. It is 

 quite possible that as the bee leaves a red clover flower (before 

 the keel closes again) the stigma may have some of the pollen 

 from the stamens of the same flower dusted on it. This is 

 called self-pollination. Darwin believed that in spite of this 

 possible self-pollination in red clover there would be no con- 

 sequent self-fertilisation, as the pollen from the preceding 



