Page:A Treatise on Geology, volume 1.djvu/173

 CHAP. VI. the fossils of the Devonian and Caledonian types of old red in Britain we have a pretty full catalogue of invertebrate.

As characteristic Devonian forms we may mention—


 * 1) Cystiphyllum damnoniense.—a. Lamellæ,
 * 2) Strombodes vermicularis.—a. Lamellæ.
 * 3) Leptæna nodulosa.
 * 4) Calceola sandalina.
 * 5) Palaeopora pyriformis.
 * 6) Strigocephalus Burtini.
 * 7) Cyrtoceras tredecimale.—a. Aperture.
 * 8) Clymenia laevigata.—a. Aperture.
 * 9) Brontes flabellifer.

The fishes of the old red sandstone which have been systematized by Agassiz, and described with much effect by Miller, are very characteristic of this palæozoic period. The classification of Agassiz, presented to the British Association in 1843, includes 63 British species, viz.:

Placoid.—Ichthyodorulites 6; Cestraciontes 1. Ganoid.—Lepidoid 33; Sauroid 13; Coelacanthoid 10.

Some of these, as well as a considerable number of the invertebrate, occur also in Russia, the only region which presents something like a fair example of the