Abstract
This brief review considers zoosporangium formation; zoospore release; and structure and physiology of the zoospore. The electron micrographs illustrate Chytridium sp., Allomyces macrogynus, Rhizidiomyces apophysatus, Rhizophydium pollinis-pini, Blastocladiella emersonii, Saprolegnia ferax, Atkinsiella dubia, pythium sp., Schizochytrium aggregatum, Oedogoniomyces sp., Monoblepharella sp. and Blastocladia ramosa.