Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/99

 Rh beings are held together in a series of near and gradual connexions.

Tins discovery, amid -the relics of past creations, of links that seemed wanting in the present system of organic nature, affords to natural Theology an important argument, in proving the unity and universal agency of a common great first cause; since every individual in such a uniform and closely connected series, is thus shown to be an integral part of one grand original design.

The non-discovery of such links indeed, would form but a negative and feeble argument against the common origin of organic beings, widely separated from one another; because, for aught we know. the existence of intervals may have formed part of the original design of a common creator; and because such apparent voids may perhaps exist only in our own imperfect knowledge; but the presence of such links throughout all past and present modifications of being, shows a unity of design which proves the unity of the intelligence in which it originated.

It is indeed true that animals and vegetables of the lower classes prevailed chiefly at the commencement of organic life, but they did not prevail exclusively; we find in rocks of the transition formation, not only remains of radiated and articulated animals and mollusks, such as Corals, Trilobites, and Nautili; but we see the vertebrata also represented by the Class of Fishes. Reptiles have been found in some of the earliest strata of the secondary formations. In the footsteps on the New Red sandstone, we have probably the first traces of Birds and Marsupialia. (See Pl. 26a. and 262) The bones of Birds occur in the Wealden formation of Tilgate forest, and those of Marsupialia in the Oolite at Stonesfield. (See Pl. 2. Figs. A. B.)