SCOLEX PROTONEPHRIDIAL SYSTEM IN CYCLOPHYLLIDEA

The ultrastructure of the scolex protonephridial system in five specie s of cestodes of the families Hymenolepididae, Dilepididae, Taeniidae is described. The following morphofunctional departments are distingui shed: ciliary (flame) cells, the <<weir>>, the terminal excretory cana ls, excretory canals. The epithelium of excretory canals is supposed t o be a polyfunctional system like tegument. The <<draining>> of cestod e body, the ensuring of the interstitial fluid current from the surfac e to the inner departments, is considered to be the main function of t he excretory system along with the osmoregulation.