TEM Study on Ultrastructure of Chitinozoan Vesicle Wall

The vesicle wall of two Ordovician Chitinozoans, Desmochitina nodosa Eisenack and Lagenochitina esthonica Eisenack, was studied with transmission electron microscope. The ultrastructure of both forms is similar and displays two-zoned character. The outer zone is porous, whereas the inner one is compact. The material forming vesicle walls is completely homogenous. Parachitina curvata Eisenack, treated as not a chitinozoan organism, has a laminar structure of vesicle wall.