Page:Popular Science Monthly Volume 9.djvu/157

Rh the future; neither of these terms signifies for her just one day. Here, again, she gives too large a signification to words. And an infant scarcely employs a single word that is not destined later to receive a more restricted meaning. Like primitive peoples, infants incline to conceive large and general ideas. The child presents, in the transitional state, mental characters which we find in the fixed state in primitive civilizations, just as the human embryo presents in the transitional state physical characters which are found in the fixed state in certain lower classes of animals.



PORTSMEN and naturalists, both at home and abroad, would do well to collect not only the skins of birds, but also to search for any peculiarity which may happen to occur in their internal structure, especially the bones and the larynx.

Some weeks since, when calling upon my friend Mr. Jamrach, the animal-dealer, I observed in the back-yard, on the dust-heap, a number of dead birds. Among them was the body of a very large crane. Mr. Jamrach allowed me to take this home, and I made several preparations of it. We now figure the very remarkable trachea, or wind-pipe, of this bird. In an ordinary bird, such as a chicken, when cutting open the skin of the throat, it will be found that the trachea forms a continuous tube, going in a direct line from the mouth to the lungs, where it bifurcates. In the crane this is not the case. Instead of passing between the two bones ordinarily known as the merry-thought, it becomes convoluted in a very remarkable manner. If this convolution had been placed immediately under the skin, first of all it would have been cumbersome to the bird; and, secondly, there would have been a great likelihood of its becoming injured. The breastbone, therefore, has been hollowed out in the middle in such a manner as to keep the trachea packed up in a beautiful box of bone. Inside this box of bone there are about thirteen inches of the trachea. The trachea enters this bony box at its lowest margin; it then runs along the bottom and ascends to the top; then takes a very sharp turn, and again descending to the bottom of the box joins the lungs in the usual way. In life this trachea is not fixed in the box, but is capable of extension and prolongation; in fact, is almost as elastic as India-rubber.

The diagram will explain this.

The curious cartilaginous-like material—reminding us of mosaic work—of which the trachea is composed, differs much in pattern in its various portions, the rings being single near the mouth, while a few 