14 THE HONEY-BEE. 



has a perforation at its extremity, through which the 

 larva emits a sticky fluid, similar to that from which 

 spider's-web or silk is made. With this the grub 

 spins for itself a cocoon, in which a further and im- 

 portant transformation takes place in the structure 

 of the insect. 



The time occupied in making this silken dress is, 

 for drone- and worker-larvae, thirty-six hours. Prin- 

 cesses, who trouble themselves to make only half- 

 cocoons, finish theirs in twenty-four hours. So soon 

 as the grubs are ready for this process, the nurse-bees 



form over the entrance to each cell a lid made of wax 

 and a sticky substance called propolis, leaving, how- 

 ever, minute perforations for the admission of air. 

 These coverings are darker than the caps of the 

 honey-cells. They are also somewhat convex over 

 worker-larvse, and over drone-grubs they stand out 

 almost hemispherically. Hence it is easy to dis- 

 tinguish the look of brood cells from that of those 



