The Life of the Individual 



111 



Feeding of larvce. 



The feeding of the larvae is one of the most ardently dis- 

 puted questions in bee activity. The chief controversy 

 arises over the source of the food, some authors claiming 

 that it is a secretion of glands, while others maintain that it 

 is regurgitated from the ventriculus. The heat of contro- 

 versy seems to have hidden from view the fact that this 

 can be determined only by investigation. An explanation 

 of the two current views involves some study of the 

 glands emptying into the alimentary canal and of the 

 ventriculus. 



There are in the head 

 of the worker bee, two 

 systems of glands (Fig. 

 59), the lateral pharyn- 

 geal (supracerebral of 

 Bordas, System No. 1 

 of Cheshire) (1GI) and 

 the salivary glands of 

 the head (postcerebral 

 of Bordas, System No. 

 2 of Cheshire) (2GI), and 

 in the thorax are found 

 the salivary glands of 

 the thorax (thoracic sal- 

 ivary of Bordas, System No. 3 of Cheshire) (Fig. 60, 

 SGI). The ducts of the two systems of salivary glands 

 unite into one median tube which enters the base of 

 the labium and opens upon the upper surface of the 

 ligula. These glands are homologous with the salivary 

 glands of other insects and presumably their secretions 

 assist in digestion although their exact function is un- 

 known. They are found in queens, drones and workers. 

 The lateral pharyngeal glands (1GI) are absent in the drone 

 and never more than rudimentary in the queen, and this 

 leads to the conclusion that they function in some way which 

 is especially useful to the worker. They are claimed by 



FIG. 59. Median longitudinal section of 

 head of worker, showing the glands 

 (1GI and 2GI). 



