A ROMANCE OF ANATOMY 159 



junction. Insects are so called because their 

 bodies are in two parts, entirely divided except 

 for an extremely slender connecting-joint. We 

 are so accustomed to accept this arrangement as 

 a common fact in nature that we seldom stop to 

 consider its real significance. It is not easy to see 

 how such a construction can be anything else than 

 a drawback to any living creature. But in the 

 hive-bee the whole arrangement seems to amount 

 to what must be called an ideal inconvenience,, 

 seeing that her honey-sac and complicated organs 

 for producing the larval food are in her abdomen, 

 with no way to them but through this fine joint. 

 Clearly there is some weighty reason for it, out- 

 balancing all other considerations, or it would not 

 exist ; and when we come to study it in connection 

 with the honey-bee's peculiar system of flight, we 

 soon arrive at the true solution. 



It has been said that the wings of the bee have 

 a perfectly symmetrical action, and that they have 

 a single fixed direction, moving up and down, 

 always at right- angles with the line of the. thorax. 

 Under the microscope each of the four wings 

 is seen as a transparent, impervious membrane, 

 intersected with fine ribs. The front wing, how- 

 ever, has a much stronger and stiffer rib running 

 the entire length of its upper edge, and it is on this 

 main rib that almost the entire force of the flight- 

 muscles is concentrated. If you look farther, you 

 will see that the under wing has a row of fine 



