Published online by Cambridge University Press: 01 May 2009
My attention has recently been called to some very interesting comments on the problem of the delimitation of the Silurian and Devonian systems, which were made by Dr. Elles in her Presidential address to Section C of the British Association at Liverpool. I am so heartily in agreement with all the principles of the modern classification of strata, as laid down by Dr. Elles, that it seems of advantage to recall very briefly how closely these principles are adhered to in using the Ludlow Bone-bed as the local base of the Devonian in England.
page 351 note 1 Elles, , “Evolutional Palaeontology in relation to the Lower Palaeozoic Rocks”: Report Brit. Assoc. Liverpool, 1923, pp. 83–107.Google Scholar
page 352 note 1 Stamp, , “The Base of the Devonian”: Geol. Mag., Vol. LX, 1923, p. 410 (Summary).Google Scholar
page 352 note 2 Barrois, , Pruvost, , and Dubois, , “Déscription de la Faune silnrodévonienne de Liévin,” 2me Fasc.: Mem. Soc. Geol. Nord., vol. vi, ii, 1920 (1922).Google Scholar
page 354 note 1 In quoting such a genus as Homalonotus—found in Silurian and Devonian— it should be noted that evolutionary palaeontology is being considered. Note also the next four forms.
page 354 note 2 pp. 175 to 183. Unfortunately care is needed in reading these pages, owing to the extraordinary large number of printer's errors amongst the figures.
page 355 note 1 Stamp, , “Les faunes des couches de passage du Silurien au Dévonien en Angleterre”: Ann. Soc. Geol. Nord., vol. xlviii, 1923, pp. 18–29.Google Scholar
page 355 note 2 This correlation is not invalidated by what I have said elsewhere about due consideration of geographical factors. The similarity of sediments indicates comparable physical conditions and the areas compared were probably not widely separated geographically.