Paper, 'On the origin and formation of roots' in a letter from T A [Thomas Andrew] Knight to the Right Hon Sir Jos [Joseph] Banks Subject: Botany Published in Philosophical Transactions as 'On the origin and formation of roots'. Sent from Knight at Elton. Read 23 February 1809. Abstract published in Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London [later Proceedings of the Royal Society of London], Volume 1, 1832. 22 December 1808