Invertase in the Hypopharyngeal Glands of the Honeybee

Abstract

SummaryThe transition from "summer" bees, in which the hypopharyngeal glands change rapidly in size and invertase content as a bee gets older, to "winter" bees, which at all ages have large glands rich in invertase, progressed gradually towards the end of the summer.In summer, glands of many foraging bees were large, and in winter those of bees feeding brood contained much invertase.The visible secretion masses in the glands are probably larval food. The invertase-containing secretion was not separately visible. It could be either scanty or abundant in large visibly active glands; it was always abundant in glands that appeared to be almost completely atrophied. The latter must actively secrete invertase, since they discharged too much to have come from reserves within them.