Shell rudimentary, entirely flat, sub-spiral, with a summit thick and very callous.

Dolabella Rumphii.

Dolabella fragilis.

D. Rumphii. Rumphius’s Dolabella.

Base thick, callous, and sub-spiral; dilated above, thin, and wedge-shaped.

FAMILY VI.
Limacinea. Five genera.

1. Onchidium. Has no shell. Two species.

Onchidium Typhæ.

Onchidium Peronii.

2. Parmacella. One species.