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and is nearly related to the genus Bibio, which is now widely distributed, being common in Europe, and in N. and S. America.

See Curtis Brit. Ent. Vol. iii. Pl. 138.

This fossil presents the under surface of the Animal.

Fig. 12. A fossil Spider from the Miocene Fresh-water formation at Aix, in Provence, in the collection of Mrs. Murchison; the under surface of the Animal is presented, and the little tubercles near the hinder part of the abdomen are Papillæ of the spinning organs, apparently, protruded by pressure.

See Kirby and Spence, Introduction to Entomology, 4th edit. vol. i. p. 204; and Herold, von der Erzeugung der Spinnen im Eie, tab. 11. Figs. 4. 9. 11. r. (Original.)

Fig. 13. From a drawing by M. Cotta of the fragment of a larger Scorpion, which is slightly delineated in Pl. 46', Fig. 2, near the forceps of the smaller and more perfect Scorpion figured in that Plate. I received this drawing from Count Sternberg, in August, 1835. (Original.)

a. Dorsal scales of the abdomen.

b. Caudal segments.

c. Intestinal Canal.?

d. Fragment of Intestinal Canal. ?

PLATE 47. V. I. p. 322, Note.

Fig. 1 and 2. Copied in part from the restoration of the Bradford, or Pear Encrinite (Apiocrirites rotundus) in Miller's Crinoidea, Pag. 19. Pl. 1. In Fig. 1. the arms are expanded, and in Fig. 2. nearly closed.

Much value is added to this and the following Plates, relating to Crinoidea, by their having been engraved (except Pl. 48.) by a Naturalist so conversant with the subjects, as Mr. James Sowerby.

The length of the jointed flexible stems has been taken from some entire stems in the collection of Mr. Channing Pearce of Bradford, near Bath. Two young individuals are attached to the calcareous Pedicle or Base of the largest specimens. (Miller.) Fig. 2. a. represents the remedial effect of calcareous secretions in repairing an injury of the joints of the stem. (Miller.)

Fig. 3. Pyriform Body of Apiocrinites rotundus, showing at its upper extremity the internal disposition of the bones surrounding the cavity of the stomach. (Original.)

Fig. 4. Vertical section of another pyriform Body, showing the cavity of the Stomach, and a series of lower cavities, or hollow lenticular spaces, between the central portions of the enlarged joints of the upper portion of the vertebral column. Miller considers these spaces as enlargements of the alimentary canal, which descends through the axis of the entire column.

The surfaces of the joints of the vertebral column. are striated with rays, which articulate with corresponding rays on the adjacent Plates, and allow of flexure without risk of dislocation; locking into one another nearly in the same manner as those figured in Pl. 49. Figs. 5. 7. 9. (Original.)

Fig. 5. Restored figure of Apiocrinites, 30-Dactylus, copied from Miller's Crinoidea, Page 96, Pl. 1. Fig. 2. (See V. I. p. 323. Note.)

B. Base and fibres of attachment.
D. Auxiliary side Arms.*

*These side arms afford a beautiful example of mechanical adaptations and compensations, which are thus described by Mr. Miller

Fig. 6. Body of Apiocrinites 30-dactylus (Nave Encrinite of Parkinson) copied from Miller's Crinoidea, P. 98. Pl. 11. (See V. I. p. 323. Note.)

Q. Pectoral Plates.

R. Capital Plates.

X. Orifice of the Mouth, or Proboscis, capable of elonga

tion for sucking in food.

Fig. 7. Another Body of a Nave Encrinite, drawn by Mr.

J. Sowerby from a specimen in the British Museum. The same is Figured by Parkinson, in his Organic Remains, Vol. II. Pl. XVII. Fig. 3. The lateral projections are the commencement of the side arms. This specimen has been corroded with acid, and consequently has lost the superficial Corrugations and

"The mechanism

in his admirable Monograph on Crinoidea, p. 97. of the joints of the side arms, where these insert into the column, is well worthy of notice, particularly in old specimens. In the earlier stage of their formation, the side arms being very short, and having then little weight, a less firm mode of adhesion to the column than becomes requisite at a subsequent period, being then sufficient, we do not find more than one joint lodged in a socket, or concave impression on the column; but when increase of size renders a stronger support necessary, two or three succeeding joints of the side arms become imbedded in this socket, (for which its extension as already noticed allows room) and these joints instead of being arranged in a series branching off at right angles from the column, become oblique, their direction inclining upwards, so as to aid in bearing the additional weight. The first joint of the side arms, where thus obliquely inserted in the columnar socket, have that portion of their circumference which is presented towards the upper part of the column, truncated, in such a curve as may fit them to the concavity of the impression where they rest against it.

The surface of these joints, which fit into the columnar impression, is smooth, being destined for adhesion only, but the articulating surface between the contiguous joints, where motion also is to be allowed, exhibits the usual mechanism of radiated ridges and furrows. These joints are convex on the side nearest the column, and concave on that most remote.

Tubercles which appear on the surface of Fig. 6. (Original.)

X. Orifice of the Mouth.

PLATE 48. V. I. p. 317.

Lily Encrinite, (Encrinites moniliformis,) from the Muschel-kalk, near Gottingen; in the Cabinet of the Marquis of Northampton. (Original.)

PLATE 49. V. I. p. 318. Note.

All the Figures in this Plate except Fig. 3, are taken from the Petrefacten of Dr. Goldfuss, Pl. LIII. and Pl. LIV. They are so fully explained in our Vol. I. p. 317 and Notes, as to supersede the necessity of any further detailed description.

Fig. 1. Restoration of the body and vertebral column of Encrinites moniliformis.'

Fig. 2. Base of attachment.

Fig. 3. Portion of the summit of a vertebral column. (Original.)

Fig. 4. Longitudinal section of Fig. 3. magnified. (See V. I. p. 319. Note.)

Figs. 5, 7, 9. Joints from different parts of the vertebral column, showing the manner in which the articulating surfaces are crenulated to admit of flexure. Figs. 6, 8, 10. Vertical sections through the axis of Figs. 5, 7, 9. showing the forms of the internal cavity for the alimentary canal.

11-26. Profile and view of the articulating surfaces of joints, from various parts of the vertebral column. (See V. I. p. 320. Note.)

PLATE 50. V. I. p. 317, et seq.

Fig. 1. Fragment of the upper portion of Encrinites moniliformis, showing the exterior of the Body, Arms, and Fingers, nearly closed around the tentacula. From a specimen belonging to Mr. Stokes. (Original.)

K. Arms.

M. Hand.

N. Fingers.

Fig. 2. Another fragment of the upper portion of the

same species, reduced one-third, showing the summit of the column, the exterior of the body, arms, and fingers, and the manner in which the Tentacula are folded when the animal is closed. See V. I. p. 321. Note. (Copied from Parkinson's Organic Remains, Vol. 2. Pl. XIV. Fig. 1.)

Fig. 3. Side View of one finger, with its tentacula, (Goldfuss, Pl. LIV.)

Fig. 4. Interior of the body. See V. I. p. 322. Note. (Miller, P. 40. Pl. II.)

E. Column.

E. Pelvis First Costal Plate Second Costal Plate. H. Scapula.

Fig. 5. Articulating surface of the base. (Goldfuss, Pl. LIV.)

Fig. 6. Dissection of the Scapula. See V. I. p. 322,

Note. (Miller.)

Fig. 7. Dissection of upper costal Plates.

(Miller.) Fig. 8. Dissection of lower costal Plates. (Miller.)

Fig. 9. Dissection of Pelvis. (Miller.)

Fig. 10. Summit of vertebral Column. (Miller.)

Fig. 11-18. Articulations of the Plates composing the

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