108 STRATIGRAPHICAL GEOLOGY 



power enough to burst forth again into surface eruptions. During 

 the later part of the period volcanic activity became rife in several 

 parts of the region, notably in Wales, Brittany, and Bohemia. 



REFERENCES 



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4 In Zittel's Palaeontology, English edition (1900), vol. i. p. 622. 



5 Hicks in Quart. Journ. Geol. Soc. vol. xxvii. p. 384, and vol. xxi. p. 39 ; 

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6 A. R. Andrew, Geol. Mag. for 1910, pp. 159, 201, 261. 



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8 Salter in Ramsay's Geology of North Wales, ed. 2, p. 62. 



9 Fearnsides, Quart. Journ. Geol. Soc. vol. Ixvi. p. 142 (1910). 



10 Ramsay, " Geology of North Wales," Mem. Geol. Surv. 2nd edition, p. 

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11 T. M'K. Hughes, Quart. Journ. Geol. Soc. vol. xxxiv. p. 137, vol. 

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13 T. T. Groom, Quart. Journ. Geol. Soc. vol. Iviii. p. .89. 



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21 See " Geological Structure of the N.W. Highlands," Mem. Geol. Surv. 



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27 J. Gosselet, Congres Geol. Internal, for 1900, Livret Guide (Ardenne). 



28 C. Malaise, Bull. Acad. Royal de Belg. for 1910. 



29 See Mobery in Geol. Foren. Stockholm. Forandl. for 1910. 



30 Schmidt, Quart. Journ. Geol. Soc. vol. xxxviii. p. 514. 



31 Pompeckj, Jahrb. K. K. Geol. Reichsaust. xlv. p. 495. 



32 Marr, Paleozoic Rocks, Sedgwick Prize Essay for. 



33 Peach in "Geol. Structure of the N.W. Highlands." 



