. A text-book of agricultural zoology. Zoology, Agricultural; Zoology, Economic. THE VERTEBRAL COLUMN. 287 in the neck ] the dorsal carry the ribs; the lumbar are found in the region of the loins ; the sacral are united into one bony mass called the sacrum, which supports to some extent the hind limbs and the pelvic arch ; the coccygeal form the tail-region. A typical vertebra (fig. 149) consists of a solid lower portion, the centrum (1 and 2), and an upper bony arch, the neural arch (4), in which lies the spinal cord. At the point where .the two halves of the neural arch meet there springs a
. A text-book of agricultural zoology. Zoology, Agricultural; Zoology, Economic. THE VERTEBRAL COLUMN. 287 in the neck ] the dorsal carry the ribs; the lumbar are found in the region of the loins ; the sacral are united into one bony mass called the sacrum, which supports to some extent the hind limbs and the pelvic arch ; the coccygeal form the tail-region. A typical vertebra (fig. 149) consists of a solid lower portion, the centrum (1 and 2), and an upper bony arch, the neural arch (4), in which lies the spinal cord. At the point where .the two halves of the neural arch meet there springs a bony spine more or less developed, the dorsal or neural spine (fig. 149, 3). On each side of the neural arch a process juts out, the zygapoxjhijsis. Fio. 149.—Lumbar Vektebra (Front view.) 1, Centrum ; 2, its facet; 3, dorsal spine ; 4, spinal foramen ; 5, anterior articulat- ing process; 6, transverse process ; 7, posterior articulating process. (Cbauveau.) (5 and 7). From the sides of the vertebra there also project a lateral process on each side, called the transverse process (6). Theoretically there is another arch below the centrum, the so-called h»mal arch, which protects the blood-system. But this can only be recognised in some animals, unless we take the ribs as partly forming the arch. It is best seen in the caudal vertebra of some fish. The vertebrae unite together jjartly by their centra and partly by the zygapophyses. When a vertebra has both faces of the centrum scooped out it is called an ampldcoelous vertebra; when one end (the anterior) is pro- jecting and the posterior concave, it is termed opisthocoilous, when concave in front and convex behind, procmlous. In the horse the cervical vertebrie will be seen to be seven in. 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 Theobald, Frederick
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1899
