ABSTRACT
The fine structure of the coelomocyts of Antedon “bifida Pennant, permitted to distinguish two morphologic types from their size, the aspect of their organelles and their activity.
The coelomic fluid of the Crinoïd can also carry an endoparasite flagellate belonging to the Kinetoplastida order, Bodonidae family, Cryptobia genus: Cryptobia antedona nov.sp.
The relations between the coelomocyts and Cryptobia antedona n.sp. are investigated.
