30 



PHYSIOLOGY OF THE HONEY-BEE. 



in the thorax, and in the head, by the aorta, which is not con- 

 traetible. Each room of the heart presents, on either side, an 

 opening for the returning blood. The blood, ''soaking through 



Fig. 16. 



NEKVOUS SYSTEM OF THE HONEY BEE. 



(Magnified. Alter Barbo.) 



the body" (Cheshire), comes in contact with the air contained 

 in the tracheal ramifications, where it is arterialized, or in 

 plainer words, renovated, before coming back to the heart. 



