that the power of the Creator had reached its extreme boundary, when fishes had been called into existence, and that our planet was destined to be the dwelling-place of no nobler inhabitants. If there be men dignified by the name of philosophers, who can hold that the present state of being, with all its moral evil, and all its physical suffering, is to be succeeded by no better and happier state, just because "all things have continued as they were" for some five or six thousand years, how much sounder and more conclusive would the inference have been which could have been based, as in the supposed case, on a period perhaps a hundred times more extended? There exist wonderful analogies in nature between the geological history of the vertebrated animals as an order, and the individual history of every mammifer--between the history, too, of fish as a class, and that of every single fish. "It has been found by Tiedemann," says Mr. Lyell, "that the brain of the fœtus in the higher class of vertebrated animals assumes in succession the various forms which belong to fishes, reptiles, and birds, before it acquires those additions and modifications which are peculiar to the mammiferous tribes." "In examining the brain of the mammalia," says M. Serres, "at an early stage of life, you perceive the cerebral hemispheres consolidated, as in fish, in two vesicles isolated one from the other; at a later period you see them affect the configuration of the cerebral hemispheres of reptiles; still later, again, they present you with the forms of those of birds; and finally, at the era of birth, the permanent forms which the adult mammalia present." And such seems to have been the history of the vertebrata as an order, as certainly as that of the individual mammifer. The fish preceded the reptile in the order of creation, just as the crustacean had preceded the fish, and the annelid the crustacean. Again, though the fact be somewhat more obscure, the reptile seems to have preceded the bird. We find, however, unequivocal traces of the feathered tribes in well-marked foot-prints impressed on a sandstone in North America, at most not more modern than the Lias, but which is generally supposed to be of the same age with the New Red Sandstone of Germany and our own country. In the Oolite--at least one, perhaps two formations later--the bones of the two species of mammiferous quadrupeds have been found, apparently of the marsupial family; and these, says Mr. Lyell, afford the only example yet known of terrestrial mammalia in rocks of a date anterior to the older tertiary formations. The reptile seems to have preceded the bird, and the bird the mammiferous animal. Thus the fœtal history of the nervous system in the individual mammifer seems typical, in every stage of its progress, of the history of the grand division at the head of which the mammifer stands. Agassiz, at the late meeting of the British Association in Glasgow, mentioned an analogous fact.