EXPLANATIONS OF THE PLATES. XXiil 
Prate I.— Fig. 1, Restoration of upper side of the elongated spe- 
cies 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, Tu- 
bercles of Péerichthys magnified. 
Puate II. — Fig. 2, Restoration of under side of Pterichthys obd- 
iongus. Fig. 1, A second specimen of Pterichthys Milleri. Fig. 3, 
Portion of wing, natural size. 
Puate II.— 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. 
Puate 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. 
Puate 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. 
Puatge VI.—Fig. 1, Cheirolepis Cummingie. Fig. 2, Magnified 
scales. Fig. 3, Magnified portion of fin. 
