Connecting Links.

191

These changes were produced only after successive ages representing vast eras of time.

From this brief review it will be seen that Darwinism assumes that the side splints so familiar in the horse of to-day indicate an ancestry in which the splints were more fully developed. In other words, the splints are the remains of organs which in the course of the development of the animal have disappeared.

Adopting this line of argument Darwin would point to the teeth in the embryo of the whalebone whale, which do not appear as the animal grows, as evidence that the giant animal in the remote past possessed teeth, so the rudimentary pelvis, hip-bone, thigh, and leg bones suggest that at one time this huge creature possessed hind legs. In the Greenland whale especially, the hip- and knee-joint, with some of their muscles, are well defined beneath the skin, so that we can imagine that at one time in the remote past the whale was a shore-loving creature, which finally became more aquatic in its habits, and the hind legs, like the many toes of the horse, disappeared.

Among the early birds of this country the wonderful Odontornithes, or birds with teeth, discovered by Professor Marsh, we have examples of connecting links striking in the extreme, and pointing to an ancestry so remote that the imagination almost fails. to grasp the reality, and the mind is bewildered by the testimony that shows conclusively that by following back the history of our feathered friends we should be led imperceptibly but surely into the domain of the reptiles.

One of the most interesting events of the scientific world of America in the past twenty years was the announcement by Professor Marsh that he had discovered in the ancient sea-bed or shore of the West the remains of birds which possessed reptilian teeth and were evidently descendants of reptiles. This announcement was received with incredulity by the scientists of Europe; but their doubts were silenced when the remains of not one but scores of specimens were deposited in the Yale museum at New Haven, showing fully the remarkable nature of the discovery. Professor Marsh states that the remains found by him represent birds which had remarkable reptilian affinities and were undoubtedly descended from some remote reptilian ancestor.

The most striking form discovered was the one called by him Hesperornis regalis. It represented a bird about six feet in length, resembling to some extent the loon of to-day. It was an aquatic bird, but flightless, being without a vestige of wings. Its neck was long, its feet extremely large, and its pointed bill, armed with sharp recurved teeth, admirably adapted for securing and holding prey. The size of the latter was not material, as the lower jaw was united in front by a cartilage, as in the snakes, giving them the power of swallowing a fish of large size. That a bird should be provided with teeth is extraordinary; but in this case they were almost identical with those of reptiles.

In referring to this bird Professor Marsh says: Having thus shown what the skeleton of Hesperornis is, and what its mode of life must have been, it

Remarkable Birds.

193

remains to consider the more important question of how the peculiar combination of general and specialised characters manifested in its structure originated. The two most striking features of Hesperornis are the teeth and the limbs, and an inquiry in regard to them first suggests itself. The teeth of Hesperornis may be regarded as a character inherited from a reptilian ancestry. Their strong resemblance to the teeth of reptiles, in form, structure, and succession, is evidence of this, and their method of implantation, in a common alveolar groove (Holcodont), conforms strictly to what we have in one well-known group of reptiles, exemplified by Ichthyosaurus. This method of insertion in the jaw is a primitive dental character, quite different from what we should naturally expect as an accompaniment of the modern style of vertebra, and is a much lower grade than the implantation of the teeth in distinct sockets (Thecodont), a feature characteristic of another group of Odontothores, of which Ichthyornis is the type. These teeth indicate unmistakably that Hesperornis was carnivorous in habit, and doubtless was descended from a long line of rapacious ancestors."

Equally remarkable was the Archæopteryx—a bird discovered in Germany. Here it is supposed was a bird but partly feathered, representing the time when feathers were developing. Its beaks were armed with teeth, while its tail was an elongation of the vertebræ, like the tail of a cat, from the sides of which grew feathers, so that when the reptilian bird flew, its tail constituted a rudder or guide. These

singular creatures, with the gigantic Pteranodons were links in the wondrous chain of early life-evidences of a remarkable ancestry. A volume could be filled in describing the many recent discoveries which naturalists of to-day consider as evidences of the correctness of the deductions of Darwin. To him the story of nature was plain and simple; the Giver of all things created life; this, acted upon by the natural conditions of its environment, produced the varieties, which, in turn, in the long eras of time, became species; from these genera were evolved; and so the change went on, populating the world.

The story of this evolution is told in the "Origin of Species," "The Descent of Man," and other works of the great naturalist, which mark epochs in the history of scientific thought.

Addresses by American Scientists: Dr. Theodore Gill-W. H. Dall -Major John W. Powell-Richard Rathbun-Charles V. Riley -Lester F. Ward-Frank Baker-Frederick W. True.

HE death of Charles Darwin, which occurred in April, 1882, created a world-wide sensation, and in every scientific society in the world resolutions of respect were passed to his memory, many of which have been collected, making in themselves a large, even ponderous, volume.

The American societies were unanimous in their appreciation of his greatness, and the memorial of the Biological Society of Washington was particularly interesting. The announcement of the death of the distinguished scientist was officially made to the society at its meeting of April 28, 1882, at which