116 Function of Glands of Siebold. 
Wolff's glands are large follicular glands (Fig. 39) situ- 
ated at the base of the mandibles. From their position we 
might suppose that their secretion was useful in forming 
wax into comb, but their large size in the queens, would 
rather argue that they, like the racemose glands, were also 
digestive in their function. I would suggest that we call 
the thoracic glands, the glands of Ramdohr; the racemose 
glands of the head, the glands of Meckel, and the other 
glands of the head glands of Siebold, in compliment to the 
excellent work which he has done in their study and elu- 
cidation. While the glands at the base of the mandibles 
may well be called from their discoverer, Wolff's glands. 
In studying the digestive organism we are greatly indebted 
to Schiemenz and Schonfeld, who have not only explained 
by use of beautiful illustrations the detailed anatomy of the 
alimentary canal, but have been equally happy in describ- 
ing the wonderful physiology of digestion in bees. Schon- 
feld from a very elaborate series of experiments concludes 
that the theory of Schiemenz and v. Siebold is not correct. 
He thinks the lower head glands secrete saliva which 
moistens the pollen, and aids in digesting it. They empty 
on the floor of the mouth just where they should pour out 
the saliva. As the queen and drones never eat pollen, but 
are fed by the workers they do not need these glands. 
Schonfeld thinks the larval food is digested pollen or chyle, 
and he claims to have found this in the true stomach of 
nurse bees. Partially digested pollen he terms chyme, which 
just before the worker larvz are to be sealed up, is fed to 
them. Thechyle and larval food he finds to contain blood 
corpuscles, and he thinks them identical with the same in 
the blood of the bee. Schonfeld fed indigestible material 
like iron particles to starving bees that had brood. The 
chyle, the larval food, but not the blood of the nurse bees 
contained this iron. This food of the larve then must be 
chyle and not a secretion. This experiment seems con- 
clusive. 
Again these same lower head glands are found in some 
insects that do not feed their larve at all, as species of Eris- 
talis—wasp colored two winged flies—and of Nepa, a genus 
of water bugs. 
