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after years of study we are still uncertain as to their characters and boundaries? We have found that no two individuals of any species are ever quite alike. We know that these variations group themselves together so as to form subordinate races or varieties— species within species. We know that again and again these minor forms or subspecies have been mistaken for real species. We know that in thousands of cases today the good and the true species of one writer will be only varieties with another. We know that every year intermediate forms are found which break down the walls between species, so that the better any group is known the smaller becomes its list of species and the greater the range of variations. There is absolutely no test by which we can separate species from races or varieties. Our actual test is the test of ignorance. When we do not know any intervening forms we regard two given species as distinct. When we find intergradations we unite these species. All naturalists have been forced to admit that species seem to be but varieties "of a larger growth," while varieties seem to be incipient species. These facts had been noticed and had been admitted long before most naturalists were willing to believe that such appearances were anything but most deceitful. Professor Cope tells us of a conchologist who kept his species of shells from varying by crushing under his heel all specimens which in any way tended to depart from the proper type. It is only by such methods as this that different species can be kept distinct from each other.

Let us take an illustration out of many that come to hand. Continued explorations bring to light from year

The species of fishes of North America.

to year new species of fishes in North American riv but the number of new forms now discovered each ye usually less than the number of old cies which are yearly proved intena Four complete lists of the fresh-wa fishes of the United States have b published by the present writer and his associates. T of 1876 enumerated 670 species; that of 1878 contain 665; the third, in 1885, only 587 species, although ward of 75 new species were detected in the nine yea which elapsed between the first and the third list. T list of 1896, with 50 more additions, contains 599 sp cies. Additional specimens from intervening localiti are found to form connecting links among the nomin species, and thus several supposed species become time merged in one, while not unfrequently the suj posed minor variations are the marks of what we mu finally regard as real species. Their reality consist simply in the extinction of the intervening forms.

The species of the Galapagos.

We have briefly reviewed the condition of this prob lem and its answers before 1836, when Charles Darwi returned to England after the voyag of the Beagle. While in South America he had been greatly impressed by two phases of the question which came to his notice during his explorations there. The first of these was the fauna of the Galapagos Islands, a rocky cluster lying well out to sea some five hundred miles off the coast of Peru and Ecuador. The sea birds of these islands are essentially the same as those of the shores of Peru. So with most of the fishes. We can see how this might well be, for both sea birds and fishes can readily pass from the one region to the other. But the land birds, as well as the reptiles, insects, and plants, are mostly peculiar to the islands. The same species are found nowhere else; but

Then again, if species be the subject of special intervention such as some have imagined, how is it that

Uncertain boundaries of species.

after years of study we are still uncertain as to their characters and boundaries? We have found that no two individuals of any species are ever quite alike. We know that these variations group themselves together so as to form subordinate races or varieties— species within species. We know that again and again these minor forms or subspecies have been mistaken for real species. We know that in thousands of cases today the good and the true species of one writer will be only varieties with another. We know that every year intermediate forms are found which break down the walls between species, so that the better any group is known the smaller becomes its list of species and the greater the range of variations. There is absolutely no test by which we can separate species from races or varieties. Our actual test is the test of ignorance. When we do not know any intervening forms we regard two given species as distinct. When we find intergradations we unite these species. All naturalists have been forced to admit that species seem to be but varieties "of a larger growth," while varieties seem to be incipient species. These facts had been noticed and had been admitted long before most naturalists were willing to believe that such appearances were anything but most deceitful. Professor Cope tells us of a conchologist who kept his species of shells from varying by crushing under his heel all specimens which in any way tended to depart from the proper type. It is only by such methods as this that different species can be kept distinct from each other.

Let us take an illustration out of many that come to hand. Continued explorations bring to light from year

The species of fishes of North America.

to year new species of fishes in North American rive but the number of new forms now discovered each yea usually less than the number of old s cies which are yearly proved intenab Four complete lists of the fresh-wat fishes of the United States have be published by the present writer and his associates. Th of 1876 enumerated 670 species; that of 1878 contain 665; the third, in 1885, only 587 species, although u ward of 75 new species were detected in the nine yea which elapsed between the first and the third list. Th TI list of 1896, with 50 more additions, contains 599 sp cies. Additional specimens from intervening localitie are found to form connecting links among the nomina species, and thus several supposed species become i time merged in one, while not unfrequently the sup posed minor variations are the marks of what we mus finally regard as real species. Their reality consist simply in the extinction of the intervening forms.

The species of the Galapagos.

We have briefly reviewed the condition of this prob lem and its answers before 1836, when Charles Darwin returned to England after the voyag of the Beagle. While in South America he had been greatly impressed by two phases of the question which came to his notice during his explorations there. The first of these was the fauna of the Galapagos Islands, a rocky cluster lying well out to sea some five hundred miles off the coast of Peru and Ecuador. The sea birds of these islands are essentially the same as those of the shores of Peru. So with most of the fishes. We can see how this might well be, for both sea birds and fishes can readily pass from the one region to the other. But the land birds, as well as the reptiles, insects, and plants, are mostly peculiar to the islands. The same species are found nowhere else; but

other species, very much like them in all respects, are found, and these live along the coast of Peru. In the Galapagos Islands, according to Darwin's notes, "there are twenty-six land birds. Of these, twenty-one, or perhaps twenty-three, are ranked as distinct species and would commonly have been assumed to have been here created, yet the close affinity of most of these birds to American species is manifest in every character, in their habits, gestures, and tones of voice. So it is with the other animals and with a large proportion of the plants. . . . The naturalist, looking at the inhabitants of these volcanic islands in the Pacific, feels that he is standing on American land."

The question, then, is this: If these species have been created as we find them on the Galapagos Islands, why is it that they should all be very similar in type to other animals living under wholly different conditions but on a coast not so very far away? And, again, why are the animals and plants of another cluster of volcanic islands the Cape Verde Islands-similarly related to those of the neighbouring coast of Africa and wholly unlike those of the Galapagos? If the animals were created to match their conditions of life, then those of the Galapagos should be like those of Cape Verde, the two archipelagos being extremely alike in respect to soil, climate, and physical surroundings. If the species on the islands are products of separate acts of creation, what is there in the nearness of the coasts of Africa or Peru to influence the act of creation so as to cause the island species to be, as it were, echoes of those on shore?

If, on the other hand, we should adopt the obvious conclusion that both of these clusters of islands have been at one time or another colonized by emigrants from the mainland, by the waifs of wind and storm, the fact of