Lapis lincis ex urina lincis coagulata invenitur.
Lapis lincis proves to be solidified urine of a lynx.
A synonym of lapis lyncis (lynx-stone) is lyngurium (lynx' urine, from Greek λυγγούριον < λύγξ lynx + οὖρον urine). Pliny the Elder in his Natural History (37, 52-3) writes that the lynx covers his urine by soil, then it hardens into stone. According to the popular medical belief, that similia similibus curantur ('likes are cured by likes'), lyngurium was held as effective medication in urolithiasis. Lynx-stone actually has nothing to do with urine. The source of its legend is Theophrastos in the 4. c. BC, and later lapidary tradition took it over without reservation. According to current theory it is supposedly a fossil. (For the cultural history and medicinal use of lyngurium see Duffin.)