Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/726

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622
EDWARD HULL ON THE CLASSIFICATION

622 EDWARD HULL ON THE CLASSIFICATION cites, and Myalina, and a large number of plants*; and we can re- cognize in the upper seams the representatives of the Coal-measures stage F, which has a very restricted area in this district. Limerick, Clare, Sfc. — Prom the observations of Messrs. Kinahan and Foot it is known that the section of the Carboniferous beds of the south-west of Ireland is similar to that of the south-east f . The following is the general section as given by these authors, with the stages to which the beds are referable. "O^ Gannister Beds. Stage E Stage D General Section, in descending order %. ft. in. ' Shales principally. Thickness not determinable. " Money-Point Flag " series about 150 Shales principally ,, 100 III. coal 1 6 Intermediate beds about 600 II. coal 2 6 Intermediate beds about 700 I. coal 6 f Grits and shales about 930

Lower Flagstone series „ 70 

q p f Shale series, with Posidonomya vetusta and P.

Becheri, Goniatites crenistria, &c 500 

Stage B Carboniferous Limestone. The stage E probably includes all the beds to the top of the series of that district. At Knockabooly Colliery, Mr. Kinahan found in the shales overlying No. II. coal Posidonomya, and a number of mi- nute univalves figured and described by Mr. Baily under the name of Loxonema minutissima, a marine form. In other places over the same coal Goniatites have been found§. Over coal No. III. the shells are similar to those from the shales over the " Bilboa coal," co. Carlow, namely Goniatites and Avicalo- pecten. Bivalves (" allied to Unio ") are found in about the same position ||. I have every hope that on the completion of a fresh survey of this district the extent and thickness of these successive stages will be clearly made out. It is sufficient for our present purpose to be certain, from the investigations of the officers of the Survey, that the general succession of the beds is similar to that in Tipperary, Kilkenny, and Carlow, and that, like these, they show the prevalence of marine conditions throughout this stage.

  • Explanation to sheet 142 of the Geological Survev maps,

t Ibid. p. 9. | Explanation to sheet 146, pp. 11 and 21. § Ibid. p. 37. || The proper identification of these bivalves is very difficult, and their rela- tions are somewhat problematical.