SOMATIC CORTICAL AND ENDOPLASMIC FINE-STRUCTURE OF REMANELLA-GRANULOSA KAHL (CILIOPHORA, KARYORELICTIDA)

Remanella granulosa KAHL (Family Loxodidae) is a flattened lancet-shap ed ciliate with 10 kineties on its right (physiologically ventral) bod y side, and two kineties along the margins of the otherwise barren lef t body side. In the right side kineties, the kinetosomes are paired, b oth being ciliated. In each pair, the rear kinetosome gives rise to a postciliary ribbon of microtubules which are stacked to form prominent lamellated postciliodesmata. The rear kinetosome has also a medium-lo ng striated kinetodesmal filament which contacts the postciliary ribbo n of the preceding pair. The antherior kinetosome has a short ribbon o f transverse microtubules. There are numerous mitochondria in the inte rkinetal ridges, but no obvious myonemes. In the two left-side kinetie s, the kinetosomes are also paired, the anterior being ciliated, the p osterior barren. Some of the latter are connected with the inner bodie s of the Muller's vesicles, likely to be gravity receptors. The endopl asm contains many skeletal spicules, especially near the right body si de, and many food vacuoles, frequently with diatoms inside. There are also envacuolated bacteria likely to be symbiotic. Some endoplasmic mi tochondria are conspicuously surrounded by membrane vesicles and lack definite cristae. Curious tiny bottle-shaped organelles, likely to be extrusomes, occur in groups between some kineties on the ciliated body side. On both sides of the body, the plasma membrane is underlain by microtubules and provided with envacuolated subpellicular pigment gran ules.