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It is without surprise that we find the discoveries of another science confirming this inference. Prof. Huxley, in a recent address on the progress of palæontology, is unable to explain the distribution of mammals at the close of the miocene period, except upon the supposition of a barrier which prevented the migration of the apes, rodents, and edentata from the southern to the northern continent. He cites the opinions of Carrick Moore and Prof. Duncan in support of the same conclusion. Further investigation will, no doubt, add to the number of facts which indicate the separation of the two continents by the ancient sea, and may even establish the fact that portions of Central America once formed parts of the Antilles group of the equatorial belt of islands.

General Michler, in his interesting report of the survey of the Atrato, observes: “All the stratified rocks on the Isthmus, exhibiting strong marks of disturbance and even dislocation since they were originally deposited, clearly prove that the upheaval which brought this narrow neck of land above the level of the ocean must have taken place at a comparatively late era. This period was undoubtedly accompanied by the protrusion of certain metamorphosed shistose (?) rocks, the doubtful nature of which has induced us to mark them as belonging to a trappean series. If Darwin had good reason to believe that the granite of South America, now rising into central peaks 14,000 feet in elevation, must have been in a fluid state since the deposition of the tertiary group, we may also do so in pronouncing the formation of the Isthmus, now linking together South and Central America, as decidedly post-tertiary.”