. On the anatomy of vertebrates. Vertebrates; Anatomy, Comparative; 1866. ANATOMY OF VERTEBRATES. 139 seat- of much greater modifications, by which they arc made sul^- servient to a variety of functions unknown in the hajmal arches of the rest of the body. Thus the two anterior hromal arches of the head perform the office of seizing and bruising the food; are armed for that purpose with teeth : and, whilst one arch is firmly fixed, the other W()rks upon it like the hammer upon the anvil. The elements of the fixed arch, called ' maxillary arch,' fig. 93, H, iv, have accordingly undergone the gr
. On the anatomy of vertebrates. Vertebrates; Anatomy, Comparative; 1866. ANATOMY OF VERTEBRATES. 139 seat- of much greater modifications, by which they arc made sul^- servient to a variety of functions unknown in the hajmal arches of the rest of the body. Thus the two anterior hromal arches of the head perform the office of seizing and bruising the food; are armed for that purpose with teeth : and, whilst one arch is firmly fixed, the other W()rks upon it like the hammer upon the anvil. The elements of the fixed arch, called ' maxillary arch,' fig. 93, H, iv, have accordingly undergone the greatest amount of change, in order to adapt that arch to its share in mastication, as well as for forming part of the passage for the respiratory medium which traverses it. Almost the whole of the upper surface of the max- illary arch is firmly united to contiguous parts of the skull Jjy rough or sutural surfaces, and its strength is increased l^y l^ony 94. Section of cranium, Crocodile appendages, which diverge from it to abut against other parts of the skull. Comparative Anatomy teaches that, of the numerous places of attachment, the one which connects the maxillary arch by its element, 'iO, with the centrum, 13, and with the descending plates of the neurapophyses, u, of the nasal segment, is the normal or the most constant point of its suspension; the bone, 20, being the pleurapophysial element of the maxillary arch: it is called the ' palatine,' because the under surface forms a portion of the bony roof of the mouth, called the ' palate,' as in fig. 98 C, 20. It is articulated at its fore part with tlie l^one, 21, which is the hroma- po|)hysial element of the arch. This bone is called the ' maxil- lary,' and is greatly developed Ijoth in length and breadth, fig. 95, 21 : it is connected with 20, figs. 94, 98 C, behind and with 22 in front, which are parts of the same arch, and with the diverging appendages of the arch, viz., fig. 95, 26, the malar bone, and fig. 98 c, 25, th
Size: 2747px × 910px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorowenrichard18041892, bookcentury1800, bookdecade1860
