any organ involved in the process of respiration

any of the bony or cartilaginous processes that project from the branchial arch and are involved with suspension feeding tiny prey

comb-like respiratory structure serving as the gill of certain mollusks

one of the often brightly colored and branching hornlike structures on the back of the nudibranch (and other related mollusks) that serve as gills

occurs in some mollusks and in tadpoles and other immature amphibians

One of the external filaments or leaflike plates connected with the tracheae of the inside of the body that form part of the respiratory system of some aquatic insect larvae and nymphs but rarely persist in the adult.

any of the bony or cartilaginous processes that project from the branchial arch and are involved with suspension feeding tiny prey