Merrilees notes (Set Dormants, p.87, n .1651) ‘... the sense of ‘hurdy-gurdy’ is well documented by historians of musical instruments: see Curt Sachs, The History of Musical Instruments (New York, 1940), pp. 271-73 and Werner Bachmann, The Origins of Bowing and the development of bowed instrumentship to the thirteenth century (London, 1969), pp. 105-11. The instrument was originally known as an organistrum, but the term symphonia became common from the twelfth century.’ The plant is identified as henbane by the DMBLS and the OED, but as hellebore in the FEW, DMF and T-L.