It cannot be said, on the ordinary view of creation, that there has not been time for the creation of mammals; many volcanic islands are sufficiently ancient, as shown by the stupendous degradation which they have suffered, and by their tertiary strata: there has also been time for the production of endemic species belonging to other classes; and on continents it is known that new species of mammals appear and disappear at a quicker rate than other and lower animals.
Although terrestrial mammals do not occur on oceanic islands, aerial mammals do occur on almost every island.

New Zealand possesses two bats found nowhere else in the world: Norfolk Island, the Viti Archipelago, the Bonin Islands, the Caroline and Marianne Archipelagoes, and Mauritius, all possess their peculiar bats.

Why, it may be asked, has the supposed creative force produced bats and no other mammals on remote islands?
On my view this question can easily be answered; for no terrestrial mammal can be transported across a wide space of sea, but bats can fly across.

Bats have been seen wandering by day far over the Atlantic Ocean; and two North American species, either regularly or occasionally, visit Bermuda, at the distance of 600 miles from the mainland.

I hear from Mr.Tomes, who has specially studied this family, that many species have enormous ranges, and are found on continents and on far distant islands.