Observations on the Entry of Dusts into the Respiratory System of the Adult Worker Honey Bee, Apis mellifera L.

Abstract

A description is given of the hair structures associated with the spiracles of the adult worker honey bee, Apis mellifera L.The surface hairs around the spiracular orifices vary in size, density and arrangement and with the exception of those of the third, fifth and sixth abdominal spiracles appear to be capable of holding back particles greater than 30 microns.When living bees were exposed to dust clouds of charcoal and cuprous cyanide, no particles were found in any internal part of the respiratory system beyond the spiracles except in the case of the trachea of the first thoracic spiracle which contained charcoal particles less than 5 microns.The mechanism of tracheal ventilation was considered and evidence accumulated to suggest that all spiracles could have an inspiratory function.