Comparative Histochemical Studies on Cestodes: II. The Distribution of Fat Substances in Hymenolepis diminuta and Raillietina cesticillus

Abstract

Staining frozen sections of cestodes with Sudan Black B demonstrated a constant increase in neutral fats from immature to gravid regions, the former containing little or none at all. In Hymenolepis the distribution of the lipid material is primarily within the medullary parenchyma, while in Raillietina, the greatest concentrations occur in a ring peripheral to the parenchymal musculature. The general pattern of distribution is in agreement with that described by earlier workers on other cestodes. The distribution of phospholipid in the immature and mature regions of both worms is very similar, the heaviest concentrations being in the subcuticular cells. However, in the posterior regions, Raillietina contains heavy blotches of phospholipid material about the egg-bearing pouches, while Hymenolepis shows only slight positive reactions in this region.