'^Ol. 55.] BEDDED EOCKS OF C0F:N'TY WATEErORD. 769 



An unexpected resemblance in the facies of the fauna of the 

 Tramore Limestones to that of the upper part of the OrtJioceras- 

 limestone is thus indicated. 



It seems therefore that Stages 2 & 3 of the Tramore Limestones 

 may be especially compared with the Echinosphserite or Cystidean 

 Limestone, and the Kuckers Shale C2 in Russia. Stage 1 may 

 possibly include beds as low as, or lower than, the Megalaspis gigcis- 

 zone (=B3 ' Yaginatenkalk,' Eussia). 



With regard to the Eaheen Shales of Newtown Head, the 

 abundance of OrtJiis argentea enables us to compare them with the 

 Orthis argentea-zone in South Wales, which comes at the top of 

 the Dicrcmograptus-shales.^ We find in them such characteristic 

 Llandeilo fossils as Calymene du]plicata and Bellerojolion ■pertwhatus. 

 We thus feel safe in placing these beds above the graptolitic shales 

 of the Carrigaghalia Series, though possibly some of the felsites etc. 

 of the top of that Series at Tramore may belong to this higher 

 horizon. But in addition to some British forms there are other 

 species peculiar to the beds, and others suggesting a Scandinavian 

 or Eussian aflSnity, as in the case of the Tramore Limestones. 

 Especially interesting is this latter group, which comprises the 

 species Amjpycc mammillatus, A. costatus, Orthis argentea, Cyhele 

 •cf. reoc, Eyolithes cf. striatus, and Glyptocystis cf. pennigera. 

 Harpes Flanagani is allied to H. Spasskii, and Remopleurides Port- 

 locki, sp. nov., to B. nanus, Leucht. All the foregoing species are 

 specially characteristic of Stage C of Eussia^ (Avhich includes the 

 Echinosphserite-limestone C 1 and the Kuckers Shale C 2), or of the 

 Scandinavian Cystidean Limestone,^ Lower CJiasmops-limestone, 

 Beyi'whia-limestone, and part of Tullberg's Middle Graptolite-shales. 

 Marr* considered the Cystidean Limestone as partly equivalent to 

 the British Lower Bala ( = Llandeilo). It seems that we may 

 especially compare the Eaheen Shales with the upper part of 

 Tullberg's' Series E of the Middle Graptolite-shales, on account of 

 the abundance of Orthis argentea and its association with species 

 of Ampyx, Trinucleus, and Cystideans. 



There are a few fossils in the Eaheen Shales which usually are 

 found only on somewhat higher horizons, such as Sphoerexochus 

 mirus and Lichas laxatus, but the former is recorded by Salter ^ 

 from Carrickadaggan (County Wexford) with the same Cystideans. 



The occurrence of this Lower Ordovician fauna with apparently 

 East European afiinities in the western part of the British Isles is of 

 great interest with reference to the questions of ancient bio-geo- 



1 Man- & Eoberts, Quart. .Tourn. Geol. Soc. vol. xli (1885) p. 476. 



2 Schmidt, Quart. Journ. Geol. Soc. vol. xxxviii (1882) p. 521, & 'Rev. 

 Ostbalt. Silur. Trilob.' pt. i (1881) p. 23. 



3 Nathorst, Sver. Geol. Undersokn. Ser. B a, No. 4 (1884) ; Moberg, ibid. 

 Ser. C, No. 109 (1890) p. 18 ; Tullberg, ibid. Ser. C, No. 50 (1882) ; Freeh, 

 •* Leth. Geogn.' pt. i, vol. ii (1897) pp. 72-77. 



4 Quart. Journ. Geol. Soc. vol. xxxviii (1882) p. 313. 

 « Tullberg, ojj. cit. pp. 19 & 20. 



6 Monogr. Palseont. Soc. ' Brit. Trilob.' 1864, p. 79. 



