254 AN INTRODUCTION TO ZOOLOGY 



It takes the worker thirty-six hours to spin its cocoon, then it 

 slowly changes into a pupa, or chrysalis (Fig. 145, N). Practi- 

 cally the entire body is made over at this time; the three regions, 

 head, thorax, and abdomen, become distinct; externally the wings 

 (w), legs, mouth parts (t, m), sting, antennae (an.), and eyes are 

 visible; and the internal changes are even more striking, the 

 larval organs developing into those of the adult, and new organs 

 appearing. After a period of rest the pupa casts off its exoskele- 

 ton, and emerges as an adult. 



The Activities of the Workers. The functions of the queen 

 and drone are few as compared with those of the worker. The 

 queen lays eggs, and the drone fertilizes the queen. But the 

 workers have a large number of varied activities, such as the build- 

 ing of honeycomb, the collection of propolis or " bee glue " 

 with which the inside of the hive is varnished, the gathering of 

 pollen or " bee bread " and its preparation as food, the feeding 

 of the queen and young bees, the carrying of water, the collec- 

 tion of flower nectar and its manufacture into honey, and the 

 cleaning, warming, ventilating, and guarding of the hive. Work- 

 ers also accomplish the pollination of flowers, raise new queens 

 when necessary, and increase the number of colonies by swarming. 



THE BUILDING OF HONEYCOMB. Wax is produced by pairs 

 of wax glands on the sterna of the last four visible abdominal 

 segments of the worker. Honey and pollen are consumed in the 

 process, and a temperature of from 97 to 98 F. is maintained. 

 When comb is to be built, the bees gorge themselves with honey, 

 and hang in dense clusters from the top of the hive for several 

 hours. Thin scales of wax are then secreted by the wax glands, 

 removed by the wax pinchers on the metathoracic legs, trans- 

 ferred to the prothoracic legs, and then to the mouth, where they 

 are mixed with saliva and kneaded by the jaws. If a new comb 

 is to be built, the wax is plastered to the roof, and in some 

 mysterious way each bee puts its contribution almost exactly 

 where it is to remain. The cells, which are gradually built up, 

 are hexagonal in shape. 



