In the British Library, a cutting from a medieval manuscript is present, which was made in Rome, Italy ca. 1513-1523. It is from the Missal of Cardinal Giuilo de’ Medici and is attributed to Matteo de Milano. It is documented as “Historiated full-page border with the text excised, of the arms (flanked by two hybrid creatures) of Cardinal Giulio de’ Medici, the Medici device of a diamond ring with three feathers and motto ‘Semper’, a half-length figure of Peter in a roundel, a cameo of the Flagellation of Christ, flowers, strawberries, birds, pearls, snail shells, and medallions inscribed in capital letters ‘Christus Deus Omniptens‘ and ‘Deus in nomine tuo salvus me fac‘ on a gold-flecked black background. Historiated initial ‘T’ of the Elevation of the Host before an altar table with an image of Anthony Abbot, introducing the Te igitur of the Canon of the Mass. A cartouche inscribed ‘Julius de Medicis, Cardin. Electus Sum. Pontif. (Clemens VII.) Anno Dom. MDXXIII’.” 
In the upper and lower borders two whitish shells may be seen in an apical view. They have both slightly over two whorls, but are slightly different (one of them seems to loosen the last whorl just before the apertural lip). They might be regarded as stylised, although if drawn by nature they could have been a dead, local helicoid species.
 BLL, Ms. Add. 352541. http://bit.ly/1cesoFQ (24.i.2014).