George Brettingham Sowerby II, A Conchological Manual — Fig. 514 to 545… (1842)
“ Ampullarina? 539. A species of Ampullaria having a thickened ledge on which the shelly operculum rests. Pachystoma, Guild. changed to Pachylabra, Sw. Fam. Plicacea. 540. Ringicula, Desh. A fossil species, front view. 541. Back view of the same. Fam. Turbinacea. 542. Turbo nicobaricus. Chrysostoma, Sw. 543. Trochus Iris. Elenchus, Humph. Fam. Purpurifera. 544. Purpura vexilla. Gen. Vexilla, Sw. 545. Priamus. Achatina priamus, Auct. The propriety of placing it in this family will depend upon the correctness of the statement made by Dr. Beck that this shell is marine, and possesses an operculum. ”
