184 BRITISH SILURIAN BRACHIOPODA. 
Wenlock Limestone—Hastnor Castle; Botvyle and Malvern; north of Canwood, Wool- 
hope district ; Rock, May Hill district ; Wenlock Edge, Dudley ; Rock Farm, Long- 
hope ; Mwdwl-Eithin ; Moel Seissog ; east of Merchlin, Plas Madoc, North Wales, &c. 
Woolhope Limestone—W oolhope, Bogmine Shelve. 
Unper Llandovery—W orcester Beacon (in conglomerate), Marloes Bay ; May Hill; 
Damory Bridge. 
Lower Llandovery—Cefn Rhyddan, &c. 
In Scotland it occurs in the Wenlock Shales of the Pentland Hills; and, according to 
Prof. M‘Coy, at Braes, one mile and a half east of Girvan, in Ayrshire. 
In Ireland it is stated by Prof. M‘Coy to be not uncommon in the slates at Doonquin, 
Dingle, County Kerry, and in the slates at Foylathurrig, Dingle. 
Abroad it was found by Dr. Lindstrom in the Island of Gothland. 
Ruyncwonecia Luanpovertana, Dav. Pl. XXIV, fig. 8—13. 
Arrypa serrata, M‘Coy. Synopsis of the Silurian Fossils of Ireland, p. 41, pl. iu, 
fig. 29, 1846. 
TEREBRATULA SERRATA, Salter. Quarterly Journal Geol. Soc., vol. vil, p. 172, 1851. 
RHYNCHONELLA — Morris. Catal. of British Fossils, p. 147, 1854. 
— — Salter. Siluria, 2nd ed., p. 230, fig. 48,1, 1859. 
— LuaNDOVERIANA (Dav.), Murchison. Siluria, 3rd ed., p. 527, 1867. 
Spec. Char. Transversely rhomboidal, wider than long. Ventral valve moderately 
convex ; beak small, incurved; sinus broad, rather shallow, and extending to not more 
than half way to the beak. Dorsal valve gently convex; fold wide, and very little 
elevated above the general convexity of the valve, and commencing likewise at about half 
way from the umbonal beak. Surface ornamented with about thirty-five small, 
obtuse, radiating ribs, of which seven or eight occupy the fold and sinus. ‘I'wo specimens 
measured— 
Length 7, width 9 lines (M‘Coy’s type specimen). 
pe HG, t ss | 7,:depthySslimes. 
Obs. ‘The name serrata cannot be adopted for this species, since it has already 
been applied by Mr. J. de C. Sowerby to a beautiful Liassic species (‘ Min. Con.,’ pl. 503, 
fig. 2, September, 1825). I have therefore proposed that of L/andoveriana, and the 
name has been adopted by Murchison in his third edition of ‘Siluria.’ Prof. M‘Coy 
remarks that his species is principally remarkable for the great number of its simple 
radiating ribs, which, together with the depression of the valves, gives a sharp serrated 
appearance to the edge. The ribs vary somewhat in number and strength in different 
specimens, the shell much resembling in its external form and appearance certain 
Jurassic and Cretaceous species. 
