Note 153 — Chapter XII · CHARACTERS OF THE SILURIAN SYSTEM IN BRITAIN. THE ARENIG VOLCANOES
Reading edition
After Messrs. Jennings and Williams, Quart. Journ. Geol. Soc. vol. xlvii. (1891), p. 371, and Horizont. Sect. Geol. Surv. Sheet 28.
Reading edition
After Messrs. Jennings and Williams, Quart. Journ. Geol. Soc. vol. xlvii. (1891), p. 371, and Horizont. Sect. Geol. Surv. Sheet 28.