Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/254

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160
PROCEEDINGS OF THE GEOLOGICAL SOCIETY.
[Jan. 27,

in believing it to be distinct, the proportions of the polypary being much greater, and the number of serratures to the inch not much more than half those in G. flaccidus as described by Professor Hall. The only other species observed at this place was a single-celled form, which I have with some hesitation referred to G. Hisingeri (=Sagittarius).

At Newtown Head, Waterford Harbour, a single-celled Graptolite occurs sparingly with numerous Caradoc-Bala fossils; this I have doubtfully referred to G. priodon.

In the adjoining county of Wexford there are several good Graptolite-localities, mostly in rocks on the shore of Courtown harbour. At Ballymoney, near Gorey, black slates occur with Diplograpsus pristis, much distorted by cleavage; and a little south of Ballymoney fishery the following species were collected,—


  • Graptolithus Hisingeri? ( = Sagittarius).
  • Didymograpsus sextans.
  • —flaccidus.
  • Diplograpsus pristis.
  • Diplograpsus mucronatus.
  • —teretiusculus.
  • Dicranograpsus ramosus.

At Ballinatray, near Gorey, fine examples of Dicranograpsus ramosus were collected. West of Ballinatray the black slates, much distorted by cleavage, contain an abundance of Diplograpsus pristis, accompanied by Cyrtograpsus gracilis; and a little south of Breanoge Head, near Courtown, a Graptolite, which I have referred to G. Sedgwicki, was collected by Mr. Galvan from a compact greenish slaty rock, such as Graptolites are not usually found in. At Tinnaglogh, four miles N.N.E. of Duncannon, Wexford, the black argillaceous slates abound with Diplograpsus pristis in a very perfect condition, showing prolonged axis and proximal termination. At Churchtown, one mile north of Tagoat, and about 7 miles S.S.E. of Wexford, the remarkable little branched Graptolite Didymograpsus caduceus, Salter, is not uncommon, accompanied by what I believe to be Graptolithus Hisingeri (=Sagittarius), and associated with fossils of Caradoc-Bala age.

In the south-west of Ireland a few miles north of the city of Limerick, and near Six-mile Bridge, in the county of Clare, a remarkably rich locality for Graptolites was discovered by Mr. G. H. Kinahan, of the Geological Survey of Ireland, on the western flank of the Slieve Bernagh mountains. The rocks consist of black-argillaceous slates, readily separating into laminae; the fossils are disclosed in the most perfect condition, the prevailing species being Diplograpsus pristis in all its varieties, resulting from pressure in various directions: examples having very long filamentary processes proceeding from the mouth of the cells appear to me to be identical with Hall's figures of D. mucronatus, this and D. dentatus, Brongniart, may, however, be only a more perfect condition of D. pristis. It is probable that the bodies I have figured and described as Theca cometoides, from this place[1], may be, as suggested by Mr. Carruthers,

  1. Journal of the Geological Society of Dublin, vol. ix. 1861, p1. 4. fig. 8.