SOLITARY AND SOCIAL BEES 



about three and a half pints of liquid honey from each. This 

 honey does not seem to thicken and crystallise out even with 

 keeping. Some species or colonies may produce a great deal 

 more : an Australian nest, for instance, has yielded 50 lb. 



The castes of the stingless bees are much more strongly 

 differentiated than those of the social species described so 

 far. The worker is the only type structurally adapted for 

 running the colony. For carrying pollen her legs are modified 

 in much the same way as those of humble bees. Her mandibles 

 often bear serrations or teeth which are thought to be of use 

 in manipulating wax. The queen, on the other hand, lacks 

 the pollen-collecting apparatus of the worker, has simpler 

 mandibles and a smaller head with somewhat smaller eyes. 

 She does not produce wax. She would be quite unable to 

 found a new colony unaided, and she must therefore be 

 accompanied by a swarm of workers. In Melipona the queen 

 is no larger than the workers, but in most species of Trigona 

 she is considerably larger; in both groups her abdomen soon 

 becomes very swollen by her enlarged ovaries. An older 

 queen is therefore easily distinguished and is too heavy for 

 flight. In fact she never leaves the nest once it is established. 



Many of the details of swarming and of the foundation 

 of new colonies are still obscure. Pairing has not been 

 accurately described, but there is probably a nuptial flight 

 something like that of the honey bee. Probably the founding 

 swarms consist of a single queen and many workers. The 

 laying queen does however tolerate some young queens, and 

 a number of them may be found living in the colony. It is 

 doubtful, however, if there is more than one laying queen 

 at any one time; the others may be merely waiting to take 

 part in swarms. 



The way in which the castes come to be differentiated is 

 still a matter of dispute. Many of the species of Trigona 



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