PART II 

 Osteology of the Rahhit 



FOR a practical study of the rabbit's skeleton, a thoroughly 

 cleaned, but otherwise rough, unmounted skeleton will be 

 found most convenient. The skull should be divided with a fine 

 saw at a little to one side of the median plane, or a second skull 

 may be provided for this purpose (cf. Fig. 88). The most useful 

 specimens for reference are: (1) a well-mounted skeleton of the 

 adult animal, showing the natural relations of the bones; and 

 (2) a rough skeleton of a young animal of from one to five weeks, 

 showing the primary composition of cartilage bones. For the 

 special study of the skull (pp. 180-195) a disarticulated specimen 

 may be employed, but the majority of the features may be made 

 out in the intact or divided skulls. The general account of the 

 skull as given below will be found to cover most of the osteological 

 points noted in the dissection. 



DIVISIONS OF THE SKELETON 



The skeleton is divisible into two main portions, namely, the 

 axial skeleton and the appendicular skeleton. The former com- 

 prises the vertebral column, the ribs, the sternum, and the skeleton 

 of the head; the latter, the supports of the anterior and posterior 

 limbs, and the associated pectoral and pelvic girdles. 



THE VERTEBRAL COLUMN 



The vertebral column (columna vertebralis) is formed of a 

 linear series of segments, the vertebrae. In accordance with its 

 function as a general support of the body, and also its relations 

 with the nervous system and the spinal musculature, the vertebrae, 

 with minor exceptions, are constructed on the same plan. Those 

 of particular regions, moreover, resemble each other specially 

 closely in function and form, so that it is possible to classify them 

 into cervical (neck), thoracic (chest), lumbar (abdominal), sacral 

 (hip), and caudal (tail) groups. 



A typical vertebra — for the characters of which any one of the 

 thoracic or lumbar series may be taken (Fig. 82, D-F)- — consists of 



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