He regarded it as a mollusc, being no doubt deceived by the slug-like appearance given by the antennae.
1, A), and agrees with the method of coiling of a mollusc without lateral torsion, such as Nautilus.
This circlet of gill-lamellae led Cuvier to class the limpets as Cyclobranchiata, and, by erroneous identification of them with the series of metamerically repeated ctenidia of Chiton, to associate the latter mollusc with the former.
In dry localities or in the absence of the intermediate host (usually a mollusc) this larva soon dies.
The ciliated larva escapes from the egg into the water and enters an intermediate host (leech, mollusc, arthropod, batrachian or fish) where it undergoes a metamorphosis into a second stage in which most of the adult organs are present.