On the Intracellular Micro-organisms of some Bostrychid Beetles

Abstract

ABSTRACT Bhizopertha dominica, F., Sinoxylon ceratoniae, L., and Bostrychoplites Zickeli, Mars., possess paired mycetomes full of bacteria-like micro-organisms. The transmission of the micro-organisms from one generation of the host to the next is carried out in the following way: Micro-organisms from the mycetomes invade the testis lobes, multiply, and mix with the sperms. These micro-organisms pass with the sperms during copulation into the bursa copulatrix of the female. From this region they pass through the micropyle of the fully formed eggs during their passage to the outside, and thus the infection is accomplished. The invasion of the testis lobes by micro-organisms causes abnormality in the process of spermatogenesis. The micro-organisms in the developing egg are first seen near the micropylar region in the peripheral protoplasm. In a later stage these micro-organisms, which have multiplied greatly by then, are to be found in between the yolk globules towards the posterior pole of the egg. From this stage onwards the course these micro-organisms follow till they reach their final destination in the larva has not been followed. The mycetomes throughout life remain quite isolated from the alimentary tract. The biological relation between the micro-organisms and their host is also discussed.