ON THE HISTOLOGY OF THE POISON APPARATUS OF CERTAIN APOCRITAN HYMENOPTERA

The histological details of 3 main components of the apocritan poison apparatus varies considerably in the representatives of the families like Eumenidae, Vespidae, Sphecidae and Xylocopidae. Excepting the size of lumen and shape of the glandular cells, all the remaining details of the poison gland are similar in the families studied. The poison sac in Eumenidae and Vespidae consists of muscles arranged in bundles and the glandular epithelium is syncytial followed by thick intima. Muscle bundles are absent in Sphecidae and Xylocopidae and at the same time the glandular epithelium is of columnar type in Sphecidae and syncytial in Xylocopidae. Intima is thin in both the cases. The alkaline gland possesses a syncytial epithelium in Eumenidae and Vespidae, columaar in Sphecidae and partially syncytial and convoluted in Xylocopidae. Intima is quite thick in Eumenidae. Outer circular muscles are present only in Sphecidae and Xylocopidae.