[Distribution of apiosomae on the body of fishes in the light of the parasite-host relationship].
The paper deals with the distribution of apiosomae over the body of fishes. The microecological condition (inhabitation on the skin, fins and gills) are analysed. Quantitative regularities are revealed in the distribution of apiosomae which are associated with differences in the inhabitation conditions on various parts of the nost's body and the character or morphological variability resulting from these differences. It was established that the fins, espeically the paired ones, and the surface of the body are most favourable for apiosomae. The gills have the least invasion density.