GENERAL CHARACTERISTICS. 31 



The bee is not provided with any discernible blood or 

 lymphatic vessels save the aorta, and its blood is colorless. 

 70. The breathing organ of the bee is spread through its 



Fig. 17. 



TRACHEAL BAG. 



(Magnified. After Barbo.) 



whole body. It is formed of membranous vessels, or traehete, 

 whose ramifications spread and penetrate into the organs, as 

 the rootlets of a plant sink down into the soil. Connected 



