Vol. 67.] SKOMER VOLCANIC SERIES. 17^ 



1896. P. T. Howard & E. W. Small. Rep. Brit. Assoc. (Liverpool) p. 797. 



'Geology of Skomer Island.' 



The authors give a brief general account of the geology of Skomer Island, 

 identifying the spherulitic felsite described by Rntley as that exposed at Tom's 

 House. They divide the rocks into basalts and porphyrites and felsites, and 

 give a brief description of the microscopic characters of those types from a few- 

 localities. They detected no fossils in the associated sedimentary rocks, but 

 regard the volcanic rocks as belonging to the Bala or Llandovery Series. 



1896. P. T. Howard & E. W. Small. ' Geological Notes on Skomer Island ' Trans. 



Cardiff Nat. Soc. vol. xxviii, pp. 55-60 & pi. i. 

 In this paper the authors published a sketch-map, on a scale of 2 inches to 

 1 mile, of Skomer, Midland, and part of the mainland, and six drawings of rock- 

 sections. The rocks illustrated are 'basalt' and 'felsite,' the former including 

 rocks which would now be classed as keratophyres. With the exception of the 

 illustrations, this paper contains substantially the same material as the British 

 Association Report for the same year. 



1897. P. T. Howard & E. W. Small. ' Further Notes on Skomer Island ' Trans. 



Cardiff Nat. Soc. vol. xxix, pp. 62-63. 

 A short description, with plate, of the section exposed in Pigstone Bay 

 (Skomer), with additional remarks on other parts of the island. The authors 

 regard the volcanic rocks of Skomer and the mainland as contemporaneous in 

 character, and as being of Bala age. 



1897. Sir Archibald Geikie. 'Ancient Volcanoes of Great Britain' vol. i. 

 p. 207. 

 Refers to the interesting alternation of basic and acid eruptives, and 

 summarizes the chief points presented by earlier authors. 



1899. E. W. Small. 'A Note on some Skomer Photographs' Trans. Cardiff Nat. 

 Soc. vol. xxx, p. 60. 

 Gives a full-page illustration of the Wick and another of the Mewstone and 

 Channel, with a brief description. 



Undated. E. W. Small. 'On the Geology of Skomer & some other Islands of 



South Pembrokeshire.' A privately printed [1899J but unpublished paper, 



4to, 18 pp., with map of Skomer on the scale of 3 inches to 1 mile, and five 



other photographic plates of views and micrographs. Two copies of this 



work were completed in 1909 by Mr. Small, who, at my suggestion, 



deposited one in the Library of the Geological Society, and kindly presented 



the other to the Library of the Geological Survey. 



Tins work contains a summary of all the important papers mentioned above, 



but presents much fresh material of the nature of measured sections and 



petrographical detail. 



The rocks are described as basalts, andesites, and felsites. 



III. The Stratigraphical Relations and Age op tre Series. 



That the Skomer Volcanic Series consists almost entirely of true 

 lava-flows has been proved by the work of previous observers, and 

 is clearly demonstrated by the individual thinness of the successive 

 layers ; the vesicular and slaggy upper and lower surfaces ; the 

 frequent occurrence of well-defined fluxion-structures ; and the 

 interlamination of the volcanic rocks Avith thick masses of sediment 

 largely made up of the igneous rocks which underlie them. 



So far as can be judged, the igneous rocks and sediments have 

 perfectly conformable relations, although in some instances the 

 former show some signs of contemporaneous erosion. It follows, 

 therefore, that these sediments must be regarded as forming part 



