External morphology of the spicules of some Trichodoridae.

External morphology of spicules in several species of Trichodoridae was studied by scanning electron and light microscopy. The bristles on the spicules observed in the light microscope in several species were revealed as small scales forming a sheath which covers most of the spicule body. Some species have smooth spicules, whereas other species exhibited complicated structures formed by projections. In all of the species studied, either a ventro-terminal or terminal opening of the spicules was observed.