‖n. pl. [ NL. See Scutum, and Branchia. ] (Zool.) An order of gastropod Mollusca having a heart with two auricles and one ventricle. The shell may be either spiral or shieldlike. [ 1913 Webster ]

☞ It is now usually regarded as including only the Rhipidoglossa and the Docoglossa. When originally established, it included a heterogenous group of mollusks having shieldlike shells, such as Haliotis, Fissurella, Carinaria, etc. [ 1913 Webster ]