4. Transverse section of another Coprolite from Lyme,
shewing the internal foldings of the plate, with sections
of scales of fishes embedded in it.
5. Exterior of a spiral Coprolite, from the Chalk Marl,
near Lewes, shewing folds and vascular impressions
analogous to those in No. 3.
6. Longitudinal section of another Coprolite, from the
same Chalk Marl, shewing the spiral manner in
which the plate was folded round itself.
7. Exterior of another spiral Coprolite, from the Chalk
at Lewes, shewing vascular impressions on its surface,
and the transverse fracture of the spiral fold
at b.
In many other figures of Plate 15, a similar
abrupt termination of the coiled plate is visible at b.
8. 9. Two other small species of spiral Coprolites in chalk;
these as well as Figs. 5, 6, 7, are probably derived
from fishes found with them in the chalk, near Lewes.
10, 11, 12. Coprolites from the Lias at Lyme, exhibiting
well defined characters of the spiral fold, with vascular
impressions on their surface.
13. Similar appearances on a Coprolite found by Dr.
Morton in the Greensand of Virginia.
14. Coprolite from the Lias at Lyme, bearing strong corrugations,
the result of muscular pressure received
from the intestines.
15. Transverse section, shewing the abrupt termination
of the folded plate in Fig. 14, and representing the
flattened form of the spiral intestine.
16. Longitudinal section of the intestinal tube of a recent
Shark, shewing the spiral valve that winds round
its interior, in the form of an Archimedes screw; a
similar spiral disposition of the interior is found in
intestines of Dog-Fishes, Figs. 1 and 2.
17. Coprolite from Lyme, containing large scales of Da-
pedium politum.
18. Coprolite from the Lias at Lyme, containing undigested
bones of a small Ichthyosaurus.
P late 15'. V. I. p. 200.
Cololite, or petrified intestines of a fossil fish from Solen-
hofen. (Goldfuss.)
P late 16. V. I. p. 202.
1. Conjectural Restoration of the Skeleton of Plesiosaurus
dolichodeirus. (Conybeare.)
2. Skeleton of Plesiosaurus dolichodeirus, in the British
Museum, from the Lias at Lyme Regis. (Scharf.
Original.)
P late 17. V. I. p. 203.
A nearly entire and unique skeleton of Plesiosaurus
dolichodeirus, 5 feet 7 inches long, from the Lias of
Street, near Glastonbury. This skeleton forms part of the
splendid series of fossil Saurians, purchased for the British
Museum, from T. Hawkins, Esq. in 1834. See V. I. p. 208,
and Note. (Hawkins.)
P late 18. V. I. p. 205, Note.
1. Under jaw of Plesiosaurus dolichodeirus, forming
part of the series last mentioned. (Original.)
2. Head of the Plesiosaurus, figured in PI. 16. Fig. 2.
seen from beneath. (Original.)
3. Ventral portion of the ribs of the Plesiosaurus, figured
in PI. 17. See V. I. p. 208. (Original.)
a. c. Central bones forming the crown of the sterno-costal
arch. b. triple series of intermediate bones between
the central bones, a. c. and the true ribs, d. d. e. e.
lower extremity of coracoid bones.