In this paper, a structural analysis of the rarely encountered hydrozoan medusa Limnocnida indica Annandale is discussed. This diploblastic, radially symmetrical organism has a body plan typical of hydrozoan medusae. In this study more emphasis was given to observation of the supporting components of its anatomical structures. Detailed observation on the distribution of supportive components including chitin, collagen, and noncellular fibers within the tissue organization has been carried out with the application of different types of staining methods. The neuromuscular arrangement at the rim of the umbrella and basal part of the gastrovascular cavity and the distribution of the neurons in the sub epithelial region of ectoderm have been analyzed both by staining and by scanning electron microscopy studies. Supporting blocks of chitin at the base of tentacles, along with statocysts, and ring-like deposition of chitin and collagen on the tentacles are documented. Distribution of collagen around radial canals in the mesoglea was found to be unique to this species. The mesoglea seems to be a storehouse for the macromolecules chitin and collagen.
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