——— cranchii (!) chelonophilus (!) Olfersii (!). Leach. Tuckey’s Congo Expedition, p. 412, 1818.

——— megalepis (!) Montagui (!) Rissoanus. _Leach._ Zool. Journal, vol. ii, p. 208, 1825.

——— membranacea. Macgillivray. Edin. New Phil. Journal, vol. xxxix, p. 171, 1845.

——— bicolor. Risso. Hist. Nat. des Productions, &c., 1826, Tom. iv, p. 383.

——— vittatus. Brown. Illust. of Conch., 1844, Pl. li, figs. 16-18.

Gymnolepas Cranchii. De Blainville. Dict. des Sci. Nat. Hist., 1824.

Pamina trilineata (!) (Var. Monstr.). J. E. Gray. Annals of Phil., vol. x, 1825.

[38] See page 136 respecting this date.

C. Scutis trilobatis: tergis intùs concavis, apicibus introrsùm leviter curvatis: carinâ modicâ, leviter curvatâ: pedunculo in capitulum coalescente.

Scuta three-lobed: terga concave internally, with their apices slightly curved inwards: carina moderately developed, slightly curved: peduncle blending into the capitulum.