Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/168

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78
PROCEEDINGS OF THE GEOLOGICAL SOCIETY.
[Dec. 8,

specifically with any of the described species, as its external surface is not known.

7. Discina? Edgelli, n. sp. Pl. IV. fig. 8.

I am uncertain as to the genus to which this shell should be referred; in external shape it looks like an Obolus, being almost circular,much depressed, and smooth. Length 8, breadth 9 lines. As it was found alone, it is impossible to determine to what formation it should be referred. Two specimens were obtained by Mr. Vicary.

8. Crania transversa, n. sp. Pl. IV. figs. 9 & 10.

Transversely oblong-oval, widest anteriorly; upper valve moderately convex, vertex about one-third of the length of the shell from the posterior margin; surface smooth or marked by concentric lines of growth. Length 6, width 7 lines. Of this shell Mr. Vicary has found two examples. Exteriorly it resembles more than one Devonianas well as Carboniferous species. The interior not having been found, it cannot be critically described; but for the sake of reference I have applied to it the provisional name of transversa. It is in all probability a Devonian shell.

9. Terbrattula?, sp. Pl. IV. fig. 11.

Of this shell a single valve has been found by Mr. Vicary in a pebble containing impressions of an Orthis Vicaryi. It bears some resemblance to T. inoequalis, F. A. Roemer (Beitr. zur Kenntniss des nordwestlichen Harzgebirge, pl. iii. fig. 3), a form belonging to the Silurian Spirifer-sandstone; but it would not be safe to identify our English valve with any of the described species of that genus, nor am I perfectly certain that it is referable to the genus Terebratula.It is longitudinally oval, broadest and rounded anteriorly, more converging posteriorly, convex, and smooth. Length 8, width 4 lines.

10. Spirifera Verneuilii, Murch. Pl. IV. figs. 19 & 20.

Bull. Soc. Geol. de France, vol. xi. p. 252, p1. xi. fig. 3 (6th April, 1840)=S. Archiaci (Murch.); also Dav. Dev. Mon. p. 23, pl. v. figs. 1-12, pl. vi. fig. 15=S. disjuncta, Sow.=S. antiquissimus and S. Davidis, Salter, Quart. Journ. Geol. Soc. vol. xx. pp. 295, 296, pl. xvii. figs. 10-13.

This is one of the commonest fossils found in the Budleigh pebbles,and is identical in shape with those Upper-Devonian specimens which occur so abundantly at Perques, near Boulogne-sur-mer, and also in Devonshire, Belgium, China, &c. It is found in company with S. macroptera, var. multicostata, Rhynchonella inaurita, Productus Vicaryi, &c. It is also the shell to which Mr. Salter applied the names of Spirifer antiquissimus and S. Davidis.

In the description of this Spirifera, Mr. Salter seems very uncertain whether it should be considered a Silurian or a Devonian fossil; for he writes, "To all appearance this is a Spirifer, and I am compelled, from the structure of its teeth [dental plates, he should say] to de-