EXPLANATION OF THE PLATES, 27 
Ah xX. 
FOSSILS OF THE CARADOC OR BALA ROCKS. 
ZOOPHYTA.—ANTHOZOA. 
Fig. 1.—a-d. STENopoRA FIBROSA, Goldfuss. 
Petrefacta Germaniz, pl. xxviii., figs. 3,4. Stenopora fibrosa, Silur. Syst., 
a. 
b, 
pl. xv., dis, fig. 6. 
Original. Branching variety of this coral, natural size, showing punctated 
surface, and horizontal section of corallites, from calcareous beds, Lower 
Silurian, Tramore Bay ; collected by Geol. Surv. of Ireland. 
ec, d. Variety lycoperdon, Hall. Favosites lycopodites, Hall, Pal. New 
York, pl. xxiii, figs. 1-3. _S. fibrosa, var. lycoperdon, Siluria, third edi- 
tion, p. 204; Foss. 28, fig. 2. 
. Original. Hemispherical variety, natural size. 
Original. Fragment of the same variety, showing radiating group of co- 
rallites, where fractured. 
. Original. Portion of surface enlarged from 1 b, showing openings of the 
irregular hexagonal corallites. From Tramore Bay, where this variety is 
very abundant, in rocks believed to be of Caradoc or Bala age. 
Urrer LuanpeI1o Rocks.—Garn, east of Arenig; south side of Arenig ; one 
mile N. W. of Llanerchymedd, Treiorwerth ; North Wales; and Pembroke- 
shire, South Wales; Mem. Geol. Surv., vol. iii., p. 258; Lancashire; 
Yorkshire ; North and South Wales ; Catal. of Brit. Foss., p. 64. 
Carapoc or Bata Rocks.—Numerous localities in Caernarvonshire, Den- 
bighshire, Montgomeryshire, and Merionethshire ; ibid., p. 260. 
From localities in Ireland, believed to be of the same age, at Knock- 
mahon; Dunabrattan Head, 'Tramore Bay,Co. Waterford; Carrickadaggan, 
and near Gorey, Co. Wexford; Slieveroe, near Rathdrum, Co. Wicklow. 
This coral is perhaps the most generally distributed of all the Silurian 
fossils both in time and space ; ranging from the Llandeilo Rocks, through 
all the series of Lower and Upper Silurian, to the Ludlow formation (Ap- 
pendix to Siluria, third edition, Table of Fossils, p. 534); and occurring at 
most of the fossil localities in these formations. 
- Fig. 2.—a, b. Perrata mQuisutcata, M‘Coy, sp. 
Brit. Pal. Foss. p. 39, pl. i. B, figs. 23 and 24. Aulacophyllum mitratum, 
a. 
Milne Edwards and Haime. British Foss. Corals, p. 280, pl. Ixvi., 
fig. 1. 
From the original figure in Brit. Pal. Foss., pl. i. B, fig. 23 ; a single turbi- 
nated corallite, showing the equidistant ‘“ septa,” or “ lamellar” divisions. 
