Lewis & Short

nĕcydălus, i, m., = νεκύδαλος (deathlike), the larva of the silk-worm, in the stage of metamorphosis preceding that in which it receives the name of bombyx: primum eruca fit, deinde, quod vocatur bombylius, ex eo necydalus, ex hoc in sex mensibus bombyx, Plin. 11, 22, 26, § 76 (acc. to Aristot. H. A. 5, 19, κάμπη, βομβύλιος, νεκύδαλος, βομβύκιον).