A NEW APICAL MICROTUBULE-ASSOCIATED ORGANELLE IN THE STERNAL GLAND OF ZOOTERMOPSIS NEVADENSIS (HAGEN), ISOPTERA.

The apical portion of the columnar cells of the sternal gland of the termite Zootermopsis nevadensis (Hagen) has been examined with the electron microscope. The cell surface abutting the cuticle is thrown into ridges upon which stand microvilli. Sections show a network of smooth membrane-bound cisternae penetrating the interior of the microvilli. At the bottom of the crevasses between the ridges, an inpocketing of the cell membrane is often found. This is surrounded by a 40-mmicro electron-opaque zone that is the insertion of a 22-mmicro microtubular component of the cell cytoplasm. The pouch-like structures and their associated microtubules are considered to represent a new cell organelle.