376 BRITISH PALAZOZOIC FOSSILS. [Bracuioropa. 
SPIRIFERA SPECIOSA (Schlot. Sp.) 
Ref. and Syn. = Terebratula speciosa Schl. Tasch. 1831. t. 2. f. 9 (not Petrefac.) 
= Trigonotreta id. Br. Leth. Geog. t. 2. f.15. = Spirifera costata Sow. G, T. 2nd Series, Vol. V. t. 55. f. 5, 6, 7. 
Sp. Ch.—Transversely fusiform, slightly compressed, valves gibbous in the middle; hinge-line very long, 
sides gradually attenuated, acute-angled, cardinal area broad, with nearly parallel sides, five, or sometimes six, 
large, obtusely-rounded, simple, radiating ribs, on each side of the mesial ridge, which is very prominent and 
rounded; mesial sinus very deep, rounded, distinct from the beak ; surface crossed with sharp transverse lines of 
growth ; beaks moderately incurved, rather small, lateral margins horizontal, front abruptly raised, with a narrow 
semielliptical wave. Width of moderate-sized specimen two inches, proportional length ;;,, depth of valves 7. 
Haying examined the original specimens described and figured by Sowerby, which are internal casts, I find 
that what he supposed to be two approximate ridges forming the mesial ridge, was really an impression of the 
slender internal septum of the entering valve, dividing the cast of the really simple mesial ridge; and a com- 
parison of these and numerous other specimens from the British localities with Eifel specimens, leaves no room 
for doubt of their identity. 
Position and Locality—Very common in the Devonian decomposing schists of Fowey, Cornwall; also in 
the similar schists of East Looe; rare in the hard, red, Devonian quartzite of Looe; Devonian schist of 
Polruan, Cornwall; in the quartzite of Highgate St Veep, Cornwall. 
SPIRIFERA VERNEUILI (Murch.) 
Ref. and Syn.—Murchison, Bull. de la Soc. Geol. de France, y. 11. t. 2. f. 3.=Spirifera calcarata Sow. G. T. 
2nd Series, Vol. V. t. 53. f. 7 (Young) + Spirifera disjuncta Sow. G. T. 2nd Series, Vol. V. t. 53. f. 8, and 
t. 54. f. 13, 14 (middle age) + 8 gigantea Sow. Geol. Trans. 2nd Series, Vol. V. t. 55. f. 1 to 4 (old). 
Sp. Ch.—Shell transversely subrhomboidal when young (up to one inch long, calcarata, Sow.) ; the sides 
gradually attenuated, and extended into long spines; with age the sides becoming gradually more parallel, giving 
a quadrate figure (disjwncta, Sow.); valves gibbous, hinge-line exceeding the width of the shell, forming con- 
tracted acute ears, hinge-area broad, but of variable width; sides subparallel or very obtusely triangular in the 
receiving yalve, flat or concave, marked with sharp reticulating strize; mesial ridge of entering valve broad, 
moderately prominent, sharply defined, particularly near the beak, by two sulci, deeper than the rest, obtusely- 
rounded near the beak, becoming obtusely-triangular towards the margin, in which it forms a wide rounded 
sinus; receiving valve with a deep mesial sinus from the beak to the front margin, obtusely defined; radiating 
ribs rounded, sharply defined, and perfectly simple on the sides, twenty-four to thirty on each side, about 
fourteen slightly smaller and dichotomous on the mesial ridge and on the sinus; four of the lateral ribs near the 
mesial ridge, occupy the same space as five or six of the mesial ones. Width, excluding the lateral spines, in a 
rather small or moderate-sized specimen, two and a quarter inches, proportional length of receiving valve ‘3, of 
entering valve {,, depth of both valves 3, width of very old individual eight inches. 
This species is easily distinguished from the S. attenuata, by the constant simplicity of its lateral ridges, 
and the same character negatives the reference of S. gigantca to SN. striata, as suggested by Mr Sharpe. Having 
carefully compared specimens from the Pas-Boulonnais of the S. Verneuili of Sir R. Murchison, with the 
type-specimens in the Cambridge collection of Sowerby’s S. dis/uncta, I can state positively their perfect 
accordance to the most minute particular. Further, having examined very great numbers of specimens from 
Cornwall of the S. calcarata, S. disjuncta, and S. gigantea, 1 can state with certainty that there is no difference 
between them. The S. calcarata with attenuated sides is the form always assumed by the small or young 
specimens, and the cardinal area in these is as wide as in the S. disjuncta, there being no foundation for Mr 
Sowerby’s supposition, that the area in this supposed species was narrow (he having only seen one valve) ; as 
the shell grows older the form becomes gradually quadrate, and is the S. disjuncta of Sowerby and Phillips, 
the latter author distinguishing those supposed species (Pal. Foss.) by stating the mesial ridge to be undefined 
in the latter: one of Sowerby’s figures, however, (fig. 8,) truthfully represents the mesial ridge sharply defined ; 
