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Fig. 4, the joints are of three degrees of magnitude; those at a being the largest, those at c. the smallest and thinnest, and those at b. of an intermediate size. The edges of c. appear at the surface only upon the salient portion of the column, Fig. 4. (See W. I. p. 328, Note.)
Figs. 6, 7, 8, 9, 12, 13. Portions of the vertebral column
of Pentacrinites basaltiformis. 6, 8, 12, show the
stellated crenulations on the articulating facets of
Figs. 14, 15, 16, 17. Articulating surfaces of joints in
different parts of the column in Pentacrinites subangularis. The mechanism of each star seems differently disposed, to modify the amount of motion required at their respective places in the column. The tubercular surfaces between the rays or petals of the star indicate the action of the intervertebral contractile fibres. (Goldfuss, Pl. LII. 1. m. m. o.p.)
PLATE 53. V. I. p. 327, Note, et seq.
1. 2. Upper parts of two nearly entire specimens of Briarean Pentacrinite, projecting in high relief from the surface of a slab, nearly two inches thick,
EXPLANATION OF PLATE 53. 87
and entirely composed of a mass of petrified Ossicula of the same species of Pentacrinite. The surface of these fossils is covered with a delicate film of Iron Pyrites, which gives them the appearance of beautiful Bronze. (Original.)
12. Continuation of the stem of Fig. 1. 2. Portion of the stem of Fig. 2.
The length of these stems when entire, was three or four times that of the fragments here remaining. Upon the stem 2", nearly all the side arms retain their places in the grooves on each side of the salient angles of the pentagonal column; they diminish in size as they approach its upper extremity. This is also distinctly seen at the upper end of the column of Fig. 1.
# First costal plate. Second costal plate. F. r.
3. Portion of a third column retaining nearly all its
E. Pelvis. # First costal Plate. From a specimen in the
Oxford Museum. (Original.)
base of the side arms, with the larger joints of the
Figs. 9, 10, 11, 12, 13. Various stellated forms on the
articulating surfaces of Vertebrae, preserved in the dislocated mass beneath Figs. 1, 2. These petalshaped, and crenated rays were probably adapted
to produce various degrees of flexibility, according
to their respective places in the column. The small
Explan ATION OF PLATE 54. 89
Miller considers to have sent off ten branches at every joint, five to the interior and five to the exterior of the petals. Fig. 14. One of the largest auxiliary side arms. Some of these contained more than 100 joints. See V. I. p. 330. (Goldfuss.) a, b, c, represent different forms of the joints at different parts of the side arms, with their nicely adjusted articulating surfaces. Figs. 15, 16, a, b, &c. Various modifications of the articulating surfaces of the joints composing the fingers and tentacula. (Goldfuss, Pl. LI.) Fig. 17. Magnified extremity of one of the tentacula. The two last joints form a very delicate pair of pincers, to lay hold on its prey. (Original.)
PLATE 54. V. I. p. 333.
Fig. 1. Caryophyllia arbuscula, nat. size, with the animals expanded. (Mem. du Mus. d’Hist. Nat. Tom. 6, Pl. 15, f. 2.)
Fig. 2. The animal of Fig. 1. magnified; as seen from above.
Fig. 3. Vertical section of the cup of Meandrina labyrinthica, with the animal placed within it. (Mem. du Mus. d’Hist. Nat. Tom. 6, Pl. 16, 10 b.)
Fig. 4. a. The common Actinia, or Sea Anemone, expanded. b. The same contracted within its external skin. (Encyc. Method. Pl. 7.2. 6.")
Fig. 5. Madrepora gyrosa. (Ellis. Zooph. Tab. 51, Fig. 2.)
* This animal has no calcareous cell, but contracts itself into a tough fleshy sac, see Fig. 4. b. At a the Tentacula are represented in a state of expansion. Some of these Polypes present the same display of brilliant colours as many of those which construct persistent
Fig. 6. Section of the animal of Meandrina viridis, and of the coral in which it is placed. Fig. 7. Animals of Meandrina limosa as seen from above, and magnified; they are placed in confluent stellated cells similar to those in Fig. 5. Fig. 8. One of the same, seen in profile, with the edges of its coralline plates behind the tentacula. (Mem. du Mus. d’Hist. Nat. Tom. 6, Pl. 15. 4.) Fig. 9. Caryophyllia Smithii, from Torquay. Nat. size. Fig. 10. The same, with its animal partially expanded, within the centre of the coral. Fig. 11. The animal expanded and seen from above. (Zoological Journal, Vol. 3. Pl. 13.)
PLATE 55. W. I. p. 350.
Fig. 1. A. B. C. Trunk, and dichotomous branches of a fossil tree, Lepidodendron Sternbergii, found in the roof of a coal-mine at Swina, in Bohemia. (Sternberg, Tab. I.)
Fig. 2. The extremity of a branch with leaves attached to it, from ten to twelve inches long.” (Sternberg,
Fig. 3. Extremity of another branch, with indications of fructification somewhat resembling a cone. (Sternberg.)
PLATE 56. V. I. p. 352, et seq.
Extinct Plants from the Coal Formation.
Fig. 1. copied from a sketch by Mr. Sopwith, of the base of a large trunk of Sigillaria standing in 1803, in the cliff at Bog Hall, near Newbiggin, on the
* By an error in copying this figure the branches are made too broad in proportion to the leaves.