. Text-book of zoology for schools and colleges. Zoology. 198 VERTEBRATE Fig. 94.—^' "Vertebra (l^^l^ar) of tbe whale, c Centrum or body; « Kenralarches; s Spinous process; a Articular process; d Transverse processes. B. Thoracic segment or vertebra, c Centrum of vertebra; n Neural arches, enclosing the canal for the spinal cord; e Spinous process; r Eibs; p Costal cartilages; 6 Breastbone or sternum. (After Owen.) uran great flexibility. From the back of the body of the ver- tebra proceed two bony arches which unite behind and thus form with the centrum a bony canal in which th
. Text-book of zoology for schools and colleges. Zoology. 198 VERTEBRATE Fig. 94.—^' "Vertebra (l^^l^ar) of tbe whale, c Centrum or body; « Kenralarches; s Spinous process; a Articular process; d Transverse processes. B. Thoracic segment or vertebra, c Centrum of vertebra; n Neural arches, enclosing the canal for the spinal cord; e Spinous process; r Eibs; p Costal cartilages; 6 Breastbone or sternum. (After Owen.) uran great flexibility. From the back of the body of the ver- tebra proceed two bony arches which unite behind and thus form with the centrum a bony canal in which the spinal cord is contained. For this reason, these arches (n) are called the " neural" arches. From the point where the neural arches unite—that is to say, from the back of the neural canal—pro- ceeds a long process, sometimes cleft at its extremity, termed the "spinous process" (s). Springing also from each neural arch is a second shorter process (a) termed the " articular pro- cess," since by means of these, as well as by the bodies, the vertebrse are jointed or " articulated " together. Also arising from the neural arches at their junction with the body of the vertebra, there may be two lateral processes (d) which are called " transverse ; This is the ordinary structure of the vertebra of a Mammal, and the names here used are those applied to the parts of the vertebra in human anatomy. In philosophical anatomy, however, these parts have proper technical names which can be emploj'ed for them in all animals filike. The nature of this work, however, will not allow of the introduction of these here. In the typical vertebra the segment is completed by a second arch, which is placed in front of or beneath the body of the vertebra, and which is known as the " haemal" arch, as it includes and protects the principal organs of the blood cir- culation (Fig. 94, B). This second arch is often only recog-. Please
Size: 1910px × 1308px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1884
