ULTRASTRUCTURAL-STUDY OF FRONTAL GLANDS IN BOTHROMESOSTOMA-PERSONATUM(PLATYHELMINTHES, TYPHLOPLANOIDA)

The frontal glands of Bothromesostoma personatum were examined using t ransmission electron microscopy. These glands have two types of rhabdo id gland cells; one type produces rhabdites and the other a different type of rod secretion (rhabdoids). The ultrastructure of the latter ty pe is described, together with their origin. Long necks containing the rhabdoids emerge from the rhabdoid gland cell bodies and extend to th e anterior end of the animal, where they release the rhabdoids. The rh abdoids are compared with the rhammites of other rhabditophoran specie s on the basis of their dye affinities, formation mechanism, and ultra structure.