Letter to Sir Charles Lyell from Dr. William Baird, 20 June 1856

Letter to Sir Charles Lyell from William Baird relating to Helix Tiarella which was published by Webb & Bartholet in 1833. He tells Lyell that no further mention was made of it in their synopsis except that it was obtained from a bag of Orchil. He advises Lyell that is would not be necessary to go to Madeira for a sample as it is readily available in the Canary Islands where it forms the major export and fetches twice as much as Madeira orchil on the London Market, with envelope, 20 June 1856.