Fig. 91.—Fragment of Ceriopora Hamiltonensis, of the natural size and enlarged. Devonian, Canada. (Original.) either united by delicate cross-bars, or which bend alternately from side to side, and become directly united with one another at short intervals—in either case giving origin to numerous oval or oblong perforations, which communicate to the whole
Fig. 92.—Fragment of Fenestella magnifica, of the natural size and enlarged. Devonian, Canada. (Original.)
Fig. 93.—Fragment of Retepora Phillipsi, of the natural size and enlarged. Devonian, Canada. (Original.)
Fig. 94.—Fragment of Fenestella cribrosa, of the natural size and enlarged. Dovonian, Canada. (Original.) plant-like colony a characteristic netted and lace-like appearance. On one of its surfaces—sometimes the internal, sometimes the external—the frond carries a number of minute chambers or "cells," which are generally borne in rows on the branches, and of which each originally contained a minute animal.
The Brachiopods still continue to be represented in great force through all the Devonian deposits, though not occurring in the true Old Red Sandstone. Besides such old types as Orthis, Strophomena, Lingula, Athyris, and Rhynchonella, we find some entirely new ones; whilst various types which only commenced their existence in the Upper Silurian, now undergo a great expansion and development. This last is especially the case with the two families of the Spiriferidœ and the Produclidœ. The Spirifers, in particular, are especially characteristic of the Devonian, both in the Old and New Worlds—some of the most typical forms, such as Spirifera mucronata (fig. 96), having the shell "winged," or with the
