Dr. Murai Éva - Gubányi András szerk.: Parasitologia Hungarica 27. (Budapest, 1994)

and kidney, where they undergo gradual destruction. Inexperienced researchers often regard the large numbers of spores (sometimes numbering several hundred), located in the macrophage centres, as if they were formed on the spot, and erroneously indicate the organ concerned as the site of development of the given parasite. Fig. 2. Variations in Myxobolus-type development. (1) Extrapiscine development. (2) Actinosporeans floating in water. (3) Sporoplasms released from actinosporeans infect the epithelial cells of fish. (4) Trophozoites formed from sporoplasms continue their development at the site of final colonization, in cells specific of the parasite species. (5) If the attacked host cell is large (muscle cell, nerve cell), the plasmodium will develop intracellularly until the spores emerge. (6) If the plasmodium commences its development in smaller cells, the attacked cell will die but the Plasmodium will become surrounded by cells of the same type as those in which development started. (7) Primarily plasmodia specific of connective tissue are surrounded by a connective tissue capsule. However, an external connective tissue envelope may encapsulate also plasmodia covered by epithelial or cartilaginous tissue. (8) After the disruption of plasmodia that develop in organs not communicating with the outworld or lacking an efferent duct, the lymph and blood circulation transports the spores to organs that have direct communication with the external world. (9) From these latter organs (gills, kidney, intestine, skin) the spores are dejected into the outworld.