« At first I had doubts respecting this being the Pecten laevis of Montagu ; but having since received a specimen from Mr.  Montagu of the true Pecten laevis, I find it to be distinct. I have therefore for the present named it similis. It is a thin semi-transparent shell, with unequal ears, of a compressed globose form, perfectly smooth, and beautifully clouded with brown. » – J. Laskey: “Account of North British Testacea” Memoirs of the Wernerian Natural History Society vol. I, Edinburgh 1811, via Google Books.