SPIRIFERA. 107 
6. Sprrirera curvata, Schlotheim. Pl. XIII, figs. 4, 4a, 5, 5a. 
1820. TrREBRATULITES cURVATUS, Schlotheim. Petref., p. 280, pl. xix, figs. 2 6, d. 
1859. Sprrirer Mopestvus, Hall. Pal. N.Y., vol. iii, p. 203, pl. xxviii, figs. la—f 
1863. —  inrLatus, Semenow and Moller. Mélange Phys. et Chim., vol. v, 
p- 665, pl. ii, figs. 2a—e. 
1863. —  oaBera. Ibid., p. 685, pl. ii, figs. 5a—e. 
1864. SprrireRa curvata, Davidson. Brit. Foss. Brach., vol. iii, pt. 6, p. 39, 
pl. iv, figs. 29—32, 33?, 34?, and pl. 
ix, figs. 26, 27. 
1882 — —_ _ Ibid., vol. v, pt. 1, p. 32, pl. i, fig. 34, 
and pl. ii, fig. 4. 
1882. SprrireR curvatus, Barrois. Mém. Soc. Géol. Nord, vol. ii, p. 246. 
2 1886. —  «yFiatus, Wenjukof. Fauna Dev. Syst. N. W. und Cent. Russl., 
p. 499, pl. xiv, fig. 15. 
Localities.—This appears to be the commonest Spirifer at Lummaton. In my 
Collection are about 100 specimens of all shapes and sizes; there are also fifty in 
the Woodwardian Museum, eleven in the British Museum, three in the Museum of 
Practical Geology, and eleven in the Torquay Museum. From Wolborough there 
are nine in Mr. Vicary’s Collection and one in the British Museum; and from 
Chircombe Bridge there is one in Mr. Vicary’s Collection. 
Remarks.—Some specimens show the finer ornamentation very distinctly. 
As a rule the valves occur united. 
Maurer! regards Sp. inflatus, Schnur,’ as a synonym of Sp. Urii. It seems to 
me more probably a young form of the narrower variety of the present species. I 
have shells of all sizes of both the wider and the narrower varieties, which are also 
linked by shells of intermediate shapes. In both cases the fold is very variable 
in depth, and in the smallest shells it is sometimes absent. In the latter case 
it is hard to decide to what species the fossils belong, but on the whole I think the 
evidence rather in favour of their being the young of the present species than of 
Sp. lineata or full-grown varieties of Sp. infima, mihi. 
Sp. modestus, Hall, exactly agrees with many of my smaller specimens. 
1 1885, Maurer, ‘ Abhand]. Grossh. Hessisch. Geol. Landes.,’ vol.i, pt. 2, p. 155, pl. vi, figs. 12, 13. 
2 1854, Schnur, ‘ Paleontographica,’ vol. iii, p. 211, pl. xxxvii, figs. 2 a—d. 
