96 THE ANATOMY OF THE HONEY BEE. 



is not collecting nectar — or, at least, the writer has not observed it — 

 while, finally, both the proventriculus and its mouth are just as well 

 developed in the queens and drones as in the workers, though neither 

 of the former are known to eat pollen, and they certainly do not 

 gather nectar. 



If the honey stomach be cut open in a freshly killed bee, the 

 pro ventricular mouth may be seen still in action.. The four lips 

 spasmodically open wide apart with a quivering motion and then 

 tightly roll together and sink into the end of the proventricular 

 lumen. This, of course, suggests their picking pollen out of the 

 nectar, but it is probably simply the ordinary process by means of 

 which the proventriculus passes any of the food in the honey stomach 

 on to the ventriculus. Nearly all insects have some such proventricu- 

 lar apparatus, which simply takes the stored food from the crop as 

 it is needed by the stomach. In some insects it forms apparently a 

 straining apparatus, which prevents coarse, indigestible fragments 

 from entering the stomach, while in some the proventriculus may be 

 a triturating organ comparable with a bird's gizzard. Bees, how- 

 ever, do not crush the pollen either in their mandibles or in the 

 proventriculus, for it occurs in perfect condition in the ventriculus. 



Hence, before the current notion that the " stomach-mouth " is 

 for the special purpose of taking pollen out of the nectar in the 

 honey stomach can be accepted it must be first demonstrated that 

 the workers eat pollen while the honey stomach contains nectar to 

 be stored in the cells, i. e., any more than is disgorged along with 

 the nectar; and, secondly, a reason must be shown why the queens 

 and drones should have a " stomach-mouth " as well developed as 

 that of the worker. In the meantime it appears most logical to 

 regard the proventricular mouth as simply the ordinary apparatus, 

 "possessed by insects in general, by means of which all of the food is 

 passed from the crop to the stomach. 



A longitudinal section through the honey stomach, the proventric- 

 ulus, and the anterior end of the ventriculus is shown in figure 45, 

 which is made from a queen. The proventriculus does not differ from 

 that of a worker, but the honey stomach is smaller and not so much 

 turned to one side (cf. fig. 44 A and B). The two muscle layers of 

 the oesophagus continue down over the walls of the honey stomach 

 (TMcl and LMcl). The outer layer of transverse fibers, however, 

 ceases at the posterior end of this organ, while the longitudinal fibers 

 continue posteriorly over the proventriculus and the ventriculus as 

 an external layer {LMcl) . A new layer of internal transverse fibers 

 begins on the proventricular walls and extends backward on the 

 ventriculus {TMcl) beneath the longitudinals. Hence the muscles 

 on the oesophagus and crop are in reverse order from those of the 

 proventriculus and ventriculus. The proventriculus is deeply in- 



