giganteus, p.
hemisphericus, P. semireticulatus (Figure 481), and P. scabriculus. Large
plaited spirifers, as Spirifera striata, S. rotundata, and S. trigonalis (Figure
482), also abound; and smooth species, such as Spirifera glabra (Figure 483),
with its numerous varieties.
(FIGURE 484. Terebratula hastata, Sowerby, with radiating bands of colour.
Mountain Limestone. Derbyshire, Ireland, Russia, etc.)
(FIGURE 485. Aviculopecten sublobatus, Phill. Mountain Limestone. Derbyshire,
Yorkshire.)
(FIGURE 486. Pleurotomaria carinata, Sowerby. (P. flammigera, Phillips).
Mountain Limestone. Derbyshire, etc.)
Among the brachiopoda, Terebratula hastata (Figure 484) deserves mention, not
only for its wide range, but because it often retains the pattern of the
original coloured stripes which ornamented the living shell. These coloured
bands are also preserved in several lamellibranchiate bivalves, as in
Aviculopecten (Figure 485), in which dark stripes alternate with a light ground.
In some also of the spiral univalves the pattern of the original painting is
distinctly retained, as in Pleurotomaria (Figure 486), which displays wavy
blotches, resembling the colouring in many recent trochidae.
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