136 THE BEB-KEEPKr'S guide; 



so intimately connected with the mouth organs, are so evi- 

 dently useful in digestion, and are so well developed in the 

 worker-bees, that they deserve full consideration. All the 

 glands have a chitinous inner intivna and outer propria, and a 

 middle epithelial membrane. 



The spinning gland of the larval bee is a simple tubular 

 gland, and is well illustrated by Schiemenz (Fig. 58). On 

 each side within the head of, the worker-bee (Fig. 59, u h g) are 

 large glands, discovered by Meckel in 1846, and fully described 

 by Siebold in 1870, which are very rudimentary in the queen 

 and entirely absent in the drone. They are often called the 

 lower head-glands. _ These are in form of the meibomian 



Fig. 57. 



Cross section of Toiig'ue in itse, after Cowan. 



I ! Labial palpi. o o Tube for sucking the nectar. 



mm Maxillae. ]> Overlapping maxillae. 



glands in our own eyelids ; that is, a long duct bears many 

 follicles rich with secreting cells, the whole looking like a 

 ■ compound leaf with small leaflets. Dr. Packard says each 

 follicle is unicellular. While all the others are acinose. The 

 ducts empty on the floor of the mouth. These glands are very 

 marked in nurse-bees, but smaller in aged bees. Schiemenz 

 believes that these glands secrete the food for the larval bees 

 and also for the laying queen. Their large size, their full 

 development only in the nurse-bees, and their entire absence 

 in queen and drones, surely seem to give great force to this 

 view. As already stated, the queen-larva is fed very liberally, 

 and almost exclusively, of this so-called bee-milk. Berlepsch 

 says that the little pollen sometimes (?) found in the digestive 

 tube of the queen-larva is accidental. The worker-larva re- 

 ceives less of this secretion, and to that fed to the drone is 



