SOLITARY AND SOCIAL BEES 



physiology. Cumber found that young queens can be 

 confined in small cages and artificially fed for a week on 

 honey. When this is done they put on weight very rapidly, 

 laying down a large amount of white reserve tissues in their 

 abdomen. Their ovaries, on the other hand, show not the 

 slightest sign of development. Large workers when similarly 

 treated have no power to increase appreciably in weight, and 

 if they are dissected the reserve tissue is found to be dis- 

 coloured brownish as it is in the old queen. 



At least some of the large workers usually show partial 

 development of their ovaries. If there is anything wrong 

 with the queen, many of them lay eggs, though these prob- 

 ably produce males only. We may conclude, therefore, that 

 there is a fundamental difference between the young queens 

 and the workers, caused in some way not yet understood, 

 such that queens can prepare themselves for hibernation 

 whereas workers cannot. There is no evidence that workers 

 ever hibernate in the climate of Western Europe or of North 

 America, and no evidence that they are capable of pairing. 

 These statements have, however, to be rather guarded owing 

 to the difficulty of separating the two castes by mere inspection. 



As noted earlier, bees play an important part in the 

 pollination of flowers. This is because they are numerous, 

 are hard and methodical workers, and are relatively large 

 insects, with long tongues. Flowers in which the nectar 

 collects at the bottom of a deep nectary are nearly always 

 fertilised by bees, more rarely by large moths. In temperate 

 climates the bees with longest tongues are some of the humble 

 bees, and it is known that these insects are essential for the 

 setting of seed by such flowers as red clover or monkshood. 

 Both in the Alps and in Norway a special species of humble 

 bee is found which visits monkshood almost exclusively. 

 Without this bee, the flower would hardly ever set any seed. 



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