Abstract
A comparative ultrahistochemical investigation of the adepidermal granules of Salmo irideus, Lebistis reticulatus and Hynobius tokyoensis was carried out using enzyme digestion methods on epoxy-embedded sections. The granules of S. irideus larvae were decomposed by periodic acid, and digested by lipase without periodic acid pretreatmenetection of the granules. The secondary postosmificated granules were digested by lipase as in S; irideus, but complete decomposition by periodic acid was not observed in this experiment; Both periodic acid and lipase changed the shape of the adepidermal granules of H. tokyoensis to suggest partial digestion, but it appeared that these granules show rather stronger resistance to periodic acid and lipase than those of S. irideus. The granules of H. tokyoensis were completely digested when the sections were treated sequentially with phospholipase C, neuraminidase and lipase.