288 BRITISH SILURIAN BRACHIOPODA. 



It must, therefore, still remain a question, subject to further discussion, whether our 

 Silurian form may not be specifically distinct from Pander's species. 



Podtion and Locality/. Strophomena imbrex, var. scmiglohosa, occurs chiefly in the 

 Wenlock formation ; but if the Ayrshire form already mentioned belongs to the same 

 species, it is found likewise in the Caradoc-Bala rocks. In the Wenlock it occurs at tlie 

 Rushall Canal, near Walsall, also in shale at the Dudley Tunnel. In the Museum of 

 Practical Geology are specimens from Malvern and May Hill, and others from Chickley 

 Common, Woolhope. It is also said to occur in the Upper Silurian (Wenlock) Shales of 

 Ferriter's Cove in Ireland. 



Upon the Continent it has been found by M. de Verneuil and Dr. Lindstrom in 

 the Upper Silurian formation of Gothland ; and by Prof. F. Schmidt at Salla, Kook, 

 Maidel, and elsewhere in Ehstland. A shell closely resembling small specimens of the 

 variety semicjlohosa has been figured by Mr. Billings from Cape Robert, in Anticosti, 

 obtained from the Hudson river group, but it may be necessary hereafter to separate 

 both this last and the Ayrshire form, and to give them, if not specific, at least varietal 

 designations. The want of interiors renders the final discrimination between these shells 

 a diflicult and uncertain subject. 



Strophomena euglypha, Hisinger (sp.). PI. XL, figs. I — 5. 



Lept^ena euglypha, Hisivyer. Antecken., pi. vi, fig. 4, 1819. 



— — Dalman. Vet. Akad. Ilandl., p. 108, pi. i, fig. 3, 1828. 



— — His. Lethasa Suecica, p. 69, pi. xx, fig. 4, 183". 



— — J.de C. Sow. Sil. Syst., p. 622, pi. xii, fig. 1, 1839. 



Ortkis — Von Buck. Mem. Soc. Geol. France, vol. ir, p. 222, pi. xii, 



fig. 26, 1840. 

 LEi'TiENA — Portlock. Geol. Londonderry, &c., p. 454, 1843. 



— — Dav. Loud. Geol. Journ., vol. i, p. 56, pi. xii, figs. 1 — 4, 1847 j 



and Bull. Soc. Geol. France, s^r. 2, vol. v, pi. iii, fig. 4, 1848. 



— — De Vern. Ibid., p. 347, 1848. 



— — Phillips and Salter. Mem. Geol. Surv., vol. iii, p. 284, 1848. 



— — Barrande. Si). Brach. Bohem., vol. ii, p. 38, pi. xxiii, figs. 



4—8, 1848. 

 Leht^na (Strophomena) euglypha, M'Coy. Brit. Pal. Foss., p. 243, 1852. 

 Strophomena euglypha, Schmidt. Sil. Form. Ehstl , Archiv. Nat. Liv., &c, vol. ii, 



p. 215, 18.58. 

 — — Salter. Siluria, 3rd edit., pi. xx, fig. 19, 1859. 



Lept^na — D'Eichw. Letlisea Rossica, per. anc, vol. i, p. 867, 1859. 



Strophomena — Lindstrom. Gotl. Brach., p. 372, 1860. 



