Scutibranchiata :: Scutibranchiata (n. pl.) An order of gastropod Mollusca having a heart with two auricles and one ventricle. The shell may be either spiral or shieldlike.
Scutibranchiate :: Scutibranchiate (a.) Having the gills protected by a shieldlike shell; of or pertaining to the Scutibranchiata.
Tectibranchiata :: Tectibranchiata (n. pl.) An order, or suborder, of gastropod Mollusca in which the gills are usually situated on one side of the back, and protected by a fold of the mantle. When there is a shell, it is usually thin and delicate and often rudimentary. The aplysias and the bubble shells are examples..
Tectibranchiate :: Tectibranchiate (a.) Having the gills covered by the mantle; of or pertaining to the Tectibranchiata.