This investigation was undertaken to further the work of Wagner who isolated coniferyl aldehyde by the treatment of wood with stannous chloride. An attempt has been made to determine whether or not coniferyl aldehyde can be obtained by the action of stannous chloride on two different lignin preparations, and thus answer the question as to whether Wagner’s coniferyl aldehyde came from the lignin of the wood or existed free in the wood. 1. It is unlikely that white pine lignin will yield coniferyl aldehyde when isolated and treated with stannous chloride according to the methods described in this investigation. 2. It is probable that Wagner’s coniferyl aldehyde existed free in the wood. / M.S.