. Natural history. For the use of schools and families. Zoology. 18 NATURAL HISTORY. motion among the vertebi-iB; while in the body of the animal the motion between them is slight. 9. In the snake tribe of Vertebrates the vertebrse are very numerous, and the motion between them is as free as in the tails of quadrupeds. Some species have over three hundred, while in man there are only twenty-four. 10. The skeletons of the different kinds of animals that I have mentioned differ from each other in many respects. For example, the fish has nothing in its skeleton th^t is like the bones of the extre


. Natural history. For the use of schools and families. Zoology. 18 NATURAL HISTORY. motion among the vertebi-iB; while in the body of the animal the motion between them is slight. 9. In the snake tribe of Vertebrates the vertebrse are very numerous, and the motion between them is as free as in the tails of quadrupeds. Some species have over three hundred, while in man there are only twenty-four. 10. The skeletons of the different kinds of animals that I have mentioned differ from each other in many respects. For example, the fish has nothing in its skeleton th^t is like the bones of the extremities in man, and that of the serpent is composed merely of vertebrse, with very short ^djMltk ribs. There are some fishes that have A^HjUj no ribs. In the turtle, as you see in Fig. ^^^^^ 6, the ribs spread out into broad plates, ^n|M^ which, joined together, make its upper . ranlBei-, covering, termed the carapace. 11. While the differences are of ex- treme variety, the skeletons of all these animals agree in one thing—in having a vertebral column. They are, therefore, classed together as vertebrate animals. 12. Connected with this grand char- acteristic of this division of the animal kingdom there is another, viz., the ar- rangement of the great central organs of the nervous system. These are in- closed in the skull and vertebral column. The brain is in the skull, and the verte- brse contain the spinal marrow, which extends from the brain through the length of the body. Each vertebra has a round opening through it, as you see in Fig. 2. When, therefore, all the ver- tebrae are joined together, there is a tube-like passage through the column. In this lies the spinal marrow, or cord, ^^Jitod rfMa^n^'''' as it is often called. In Fig. 7 you have. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Hooker, Wor


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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1883