■658 DR. G. J. HINDE AND MR. HOWARD FOX ON [Nov. 1895, 



fauna of this division (excluding the radiolaria) are the number of 

 the species of trilobites, of which 8 have been recognized by 

 Dr. Woodward, and the numerous diminutive brachiopods, mainly 

 of the genera Producius, Chonetes, and Orthotetes. Crinoids also 

 must have been abundant, judging by the number of the casts of 

 the stem-joints. Corals are few in number, and tbey are markedly 

 small types. The cephalopods include Goniatites mixolobus, Phill., 

 G. sjrirorhis, Phill., and two other undetermined species. The Radio- 

 larian Beds are probably continuous round the margin of the Culm 

 Measures, but for the most part only the microscopic organisms are 

 recognizable in them — the larger fossils being known only from 

 some thin shaly layers in the Barnstaple district. 



It is only at Beeny Cliff, near Boscastle, and in the section in 

 the town of Tavistock that we have observed the beds above the 

 Radiolarian (Codden Hill) rocks, and in these localities they pass 

 up conformably into fine dark shales in which no fossils were 

 observed. According to Mr. Ussher, 1 the Codden Hill Beds of 

 Lifton Wood, near Launceston, are overlain by yellowish-brown 

 conglomeratic beds, those at Ugbrooke Park 2 and near Oldchard, in 

 the Chudleigh district, by coarse, partially conglomeratic sandstones, 

 and those at Ramshorn Down 3 by sandstones and shales with 

 traces of plants. It is hardly probable that the Radiolarian Beds 

 are directly succeeded by beds of coarse clastic materials, and the 

 fact that the Ugbrooke Park conglomerates contain fragments of 

 dark cherty rock similar to the Radiolarian Beds below suggests, 

 as Mr. Ussher remarks, a prior denudation of the lower rocks. 



Distinctly higher in the Culm Measures than the Radiolarian 

 Beds are some dark nodular shales near Instow in North Devon. 

 These contain Goniatites Listeri, Mart., a fossil which also occurs 

 in the Carboniferous Limestone ; and two species of fishes which 

 elsewhere are found in the Millstone Grit and Coal Measures. 

 Mr. T. M. Hall 4 places these beds on the horizon of the Millstone 

 Grit ; but it remains to be determined whether these beds really 

 belong to that horizon. 



X. Correlation oe the Radiolarian Beds. 



The rocks most nearly related to the Radiolarian Beds and the 

 associated strata of the Lower Culm Measures in the South-west 

 of England are to be found in the Culm Series of Westphalia, 

 Nassau, and the Harz. In the first-named region, at Aprath, 

 between Elberfeld and Wiilfrath, Dr. E. Kayser 5 states that the 

 Culm beneath the Flotzleerer Sandstein, or Millstone Grit, consists 

 of alum shales, Posidonia-shales, kieselschiefer, and limestone, and 

 beneath this latter is the Carboniferous Limestone, at first only 

 slightly developed below the Culm, but gradually, increasing in 



1 Proc. Som. Archseol. & Nat. Hist. Soc. vol. xxxviii. (1892) p. 128. 



2 Ibid. p. 140. 3 Ibid. pp. 134, 144. 



4 ' Sketch Geol. Devonsh.' 1878, repr. p. 10. 



5 Jahrb. d. konigl. Preuss. geol. Landesanst. f. 1881, p. 53. 



