Third letter from William Crawford Williamson, on his paper 'On the organisation of the fossil plants of the coal-measures. Heterangium Tilioeoides (Will.) and Kaloxylon Hookeri' to the Secretary of the Royal Society He wishes to avoid disagreements with the Council, but believes they are 'making a mistake in the present instance'. His remarks on his new discovery will be ready in a few days. Subject: Botany [Published in Proceedings of the Royal Society, 1887]. 7 May 1887