the historian. In view, then, of the unfortunate imperfection of the geological record _per se_, as well as of the no less unfortunate limitation of our means of reading even so much of the record as has come down to us, I conclude that this record can only be fairly used in two ways. It may fairly be examined for positive testimony against the theory of descent, or for proof of the presence of organic remains of a high order of development in a low level of strata. And it may be fairly examined for negative testimony, or for the absence of connecting links, if the search be confined to the larger taxonomic divisions of the fauna and flora of the world. The more minute these divisions, the more restricted must have been the areas of their origin, and hence the less likelihood of their having been preserved in the fossil state, or of our finding them even if they have been. Therefore, if the theory of evolution is true, we ought not to expect from the geological record a full history of _specific_ changes in any but at most a comparatively small number of instances, where local circumstances happen to have been favourable for the writing and preservation of such a history. But we might reasonably expect to find a general concurrence of geological testimony to the larger fact--namely, of there having been throughout all geological time a uniform progression as regards the larger taxonomic divisions. And, as I will next proceed to show, this is, in a general way, what we do find, although not altogether without some important exceptions, with which I shall deal in an Appendix. There is no _positive_ proof _against_ the theory of descent to be drawn from a study of palæontology, or proof of the presence of any kind of fossils in strata where the fact of their presence is incompatible with the theory of evolution. On the other hand, there is an enormous body of uniform evidence to prove two general facts of the highest importance in the present connexion. The first of these general facts is, that an increase in the diversity of types both of plants and animals has been constant and progressive from the earliest to the latest times, as we should anticipate that it must have been on the theory of descent in ever-ramifying lines of pedigree. And the second general fact is, that through all these branching lines of ever-multiplying types, from the first appearance of each of them to their latest known conditions, there is overwhelming evidence of one great law of organic nature--the law of gradual advance from the general to the special, from the low to the high, from the simple to the complex.