This experiment of Mr. Parkinson was highly important, as proving the previously almost incredible fact, that animal membrane, when hermetically sealed, as it were, in the solid stone, was as indestructible as the rock itself. It suggested, too, the probability that vestiges of other animal tissues might be traced in organic remains, and encouraged subsequent observers to seek for evidence of the soft parts of animal bodies entombed in the strata. It was the first step in the right direction, and led to the detection of many highly interesting phenomena. In Dr. Buckland's Bridgewater Essay will be found figures and descriptions of the eyes of crustacea: of the wings, elytra or wing-covers, and the integuments of the body of insects; of the skin of reptiles; and, in the "Wonders of Geology," and "Medals of Creation," of the membranes of the air-bladder, and of the capsule of the eye of fishes; of the soft parts of the animalcules called foraminifera, &c. The bodies of mollusca, or shell-fish, converted into a dark brown mass (_mollushite_), occur in such abundance in some deposits, as to yield a rich manure from the quantity of phosphate of lime. The excrementitious substances termed by Dr. Buckland "Coprolites," are also used for agricultural purposes. [Illustration: Plate XXXV.] PLATE XXXV. The subjects here figured are Fossil Corals. Fig. 1. (_Syringopora ramulosa_.) A fragment of another species of the coral previously described; from the mountain limestone. Fig. 2, represents four connected tubes of the recent organ-pipe coral (_Sarcinula musica_) of New Holland, to show the structure of this type of Zoophytes. Coloured figures of the live polypes of this coral are given in Wonders of Geology, sixth edition, vol. ii. plate vi. Fig. 3. A polished slab of marble, the white markings in which are produced by sections of the tubes of the same species of coral as that represented in fig. 1. Fig. 4. (_Catenipora escharoides._) The fossil here delineated is well known to collectors by the name of "_chain-coral_" derived from the elegant cateniform markings produced by transverse sections of the parallel tubes, which being of an oval form, and in close apposition, give rise to chain-like figures, as shown in figs. 5 and 6. From Dudley.