For the study of those bee diseases with which no specific organisms have so far been identified, it is important to be able to eliminate bees dying of old age, and this cannot be done with certainty by observing outward symptoms. However, the age of bees, which normally work almost incessantly for about six weeks and then die, may be determined with some accuracy from a study of the brain-cells. With advancing age the cytoplasm of these cells undergoes gradual reduction peripherally, until in senescence only a vestige is left surrounding the nucleus.
The condition of the head-glands, including a pair of œsophageal glands which do not appear to have been previously recorded, gives some indication of age in normal healthy bees.
- Copyright © 1920 by the Company of Biologists Ltd.