SOLITARY AND SOCIAL BEES 



extent, and they are essentially workers. These workers now 

 do nearly all the work of the summer-nest, and the old spring 

 female becomes a queen who guards the nest and lays most 

 of the eggs. The result of this activity is the production of 

 another autumn brood of males and females. It seems from 

 the observations of Stockhert and Noll that the autumn 

 females all come from eggs laid by the queen, whereas the 

 males come from unfertilised eggs laid either by the queen 

 or by some of the workers. Thus throughout the whole 

 seasonal cycle females are always derived from fertilised eggs 

 which are all laid by the original spring female. 



It seems, at any rate in the Halictus studied by Stockhert, 

 that where two or three spring females combine to make one 

 nest, only one of them survives to act as queen when the 

 workers appear. Thus the situation seems very like that 

 already described for the wasp Polistes gallicus in north Italy, 

 where colonies may be founded by several queens, but in 

 which one queen becomes the dominant egg-layer and is 

 the only one who remains in the nest after the workers have 

 hatched. Apparently in some species, such as Halictus 

 maculatus, rare in Britain, several spring females may con- 

 struct separate nests with a common entrance-gallery. When 

 such a nest is fully developed, with each separate part contain- 

 ing its own brood of workers, the single entrance is as busy 

 as the entrance of the much larger colonies of a humble 

 bee. 



The colonies of Halictus show a type of social life which 

 is primitive because they are always small (probably six to 

 ten workers) while the workers are little different from the 

 queens and still lay some of the eggs. Probably the growth 

 of the colony is much restricted because they have retained 

 the normal subterranean habits of solitary species. Each 

 separate cell has to be excavated, and though a group of cells, 



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