FPXPLANATION OF THE PLATES. 19 
PLATE ‘Vill 
FOSSILS OF THE LLANDEILO ROCKS. 
MOLLUSCA.—BRACHIOPODA. 
Fig. 1.—a, 6. LiNGULA ATTENUATA, Sowerby. 
Silurian System, pl. xxii., fig. 13, 1839; and Siluria, third edition, p. 55; 
Foss. 10, fig. 18, and pl. v., fig. 16; British Silurian Brachiopoda, by 
Thomas Davidson, Esq., Pal. Soc., 1866, p. 44, pl. ili., figs. 18-27. 
a, b. From the original figures in the Silurian System above cited, aided by 
specimens in the Mus. Geol. Surv. of Ireland, from Pont Ladies, Llan- 
deilo, and Panteg, Caermarthenshire. 
LiANpDEILo FrLags.—It occurs in the Llandeilo Flags only, according to Mr. 
Salter. Very characteristic examples, are found at Llandeilo and Shelve ; 
also at Coed Sion, Llangadock ; Middleton, east of Cherbury ; Rorington, 
Salop ; Carneddau, Builth district, &c. ; Brit. Sil. Brach. pp. 44, 45. 
Fig. 2.—a, b. OBOLELLA? PLUMBEA, Salter, sp. 
Lingula plumbea, Salter, Siluria, third edition, p. 50; Foss. 8, fig. 1. 
Obolella plumbea, Id. Memoirs Geological Survey, vol. iii., p. 334, pl. 
xi. B, fig. 10; Brit. Sil. Brach., p. 61, pl. iv., figs. 20-27. 
a,b. From the original figures in Memoirs Geological Survey, vol. iii., pl. 
xi. B, figs. 10,10 a. 
Lower LianpetLo.—West of the Stiper stones, Shropshire, abundant, par- 
ticularly at White Grit Mine, Shelve; it is also found at Ty-Obry, two 
miles east of Portmadoc. Brit. Sil. Brach., p. 60. 
Fic. 3.—a, 6. StPHONOTRETA MICULA, M‘Coy. 
Brit. Pal. Foss., p. 188, pl. i. H, fig. 3; Siluria, third edition, p. 212; 
Foss. 35, fig. 3; Brit. Sil. Brach., p. 76, pl. vill., figs. 2-6. 
a. Original. A group of these minute Brachiopod shells from a slab of black 
shale, Wyeford, Builth ; Museum, Geological! Survey of Ireland. 
b. Original. One of these shells, enlarged three diameters, showing perfo- 
rated beak, and the irregular spiny surface ; the longitudinal fissure, as 
suggested by Mr. Davidson, being probably due to pressure. 
LianprEILo Fracs.— It abounds at Wyeford, near Builth, also at Conway 
Castle ; in Scotland it was found by Professor Harkness in the Graptolite 
shales at several localities about nine miles east of Dumfries, also near 
