SECTION IV.

Illustration of a fault in the Burn of Eathie, Cromartyshire. (See pages 204 and 205.)

EXPLANATIONS OF THE PLATES.

Plate I.--Fig. 1, Restoration of upper side of the elongated species of Pterichthys (P. oblongus,) referred to in page 47. Fig. 2, Pterichthys Milleri. Fig. 3, Part of tail of elongated species, showing portions of the original covering of rhomboidal scales. Fig. 4, Tubercles of Pterichthys magnified.

Plate II.--Fig. 2, Restoration of under side of Pterichthys oblongus. Fig. 1, A second specimen of Pterichthys Milleri. Fig. 3, Portion of wing, natural size.

Plate III.--Fig. 1, Coccosteus cuspidatus. Fig. 2, Impression of inner surface of large dorsal plate. Fig. 3, Abdominal lozenge-shaped plate. Fig. 4, Portion of jaw, with teeth.

Plate IV.--Fig. 1, Restoration of Osteolepis major. Fig. 2, Scales from the upper part of the body magnified. Fig. 3, Large defensive scale which runs laterally along all the single fins. Fig. 4, Under side of scale, showing the attaching bar. Fig. 5, Enamelled and punctulated jaw of the creature. Fig. 6, Magnified portion of fin, showing the enamelled and punctulated rays.

Plate V.--Fig. 1, Dipterus macrolepidotus. This figure serves merely to show the place of the fins and the general outline of the ichthyolite. All the specimens the writer has hitherto examined fail to show the minuter details. Fig. 2, Glyptolepis leptopterus. Fig. 3, Single scale of the creature, showing its rustic style of ornament. Fig. 4, Scale with a nail-like attachment. Fig. 5, Under side of scale. Fig. 6, Magnified portion of fin. Fig. 7, Shells of the Old Red Sandstone.

Plate VI.--Fig. 1, Cheirolepis Cummingiæ. Fig. 2, Magnified scales. Fig. 3, Magnified portion of fin.

Plate VII.--Fig. 1, Cheiracanthus microlepidotus. Fig. 2, Magnified scales. Figs. 3, 4, 5, 6, 7, 8, Vegetable impressions of the Old Red Sandstone.

Plate VIII.--Fig. 1, Diplacanthus longispinus. Fig. 2, Diplacanthus striatus. Fig. 3, Magnified scales of fig. 1. Fig. 4, Spine of fig. 2, slightly magnified.

Plate IX.--Fig. 1, One of the tail flaps of the gigantic Crustacean of Forfarshire. Fig. 2, Reticulated markings of Carmylie.

Plate X.--Fig. 1, Cephalaspis Lyellii, copied from Lyell's Elements of Geology, Fig. 2, Holoptychius nobilissimus, copied on a greatly reduced scale from Murchison's Silurian System, Fig. 3, Scale of Holoptychius, natural size. Fig, 4, Tooth of ditto, also natural size. These last drawn from specimens in the collection of Mr. Patrick Duff, of Elgin.

DIRECTIONS TO THE BINDER.

Sheet of Sections to front Title-Page. Plate I. to front page 44 II. " " " 46 III. " " " 48 IV. " " " 66 V. " " " 72 VI. " " " 78 VII. " " " 82 VIII. " " " 84 IX. " " " 136 X. " " " 154

NEW WALKS IN AN OLD FIELD;

OR,

THE OLD RED SANDSTONE.