by William Swainson, Zoological Illustrations — Vol I. Pl… (1820)
“ A very perfect one exists in my father's collection which measures only two inches one line long: it differs slightly in wanting the lower white band and its inferior border: there is also an additional small plait between the second and third, a variation not uncommon in the Linnæan Volutes, and which lessens the importance of this character as a specific distinction. ”
