40 



MAMMALIAN ANATOMY 



FIG. 12. 



Dorsal Side 



to another. The end near the back is the dorsal end, or one bone is 

 dorsal to another. Inasmuch as inner and outer may be confused with 

 internal and external, the side of a bone near the median plane is 



called the medial side, and the 

 opposite side is called the lat- 

 eral side. Lines connecting the 

 dorsal and ventral sides are 

 termed dorso- ventral, and longi- 

 tudinal lines are termed cephalo- 

 caudal. 



The use of intrinsic terms 

 may be still further extended ; 

 for example, the end of a rib 

 attached to the vertebral column 

 may be known as the vertebral 

 end, and the end near the 



sternum as the sternal end. 

 Ventral Side ^T~ ^ Seveml othei . terms haye 



Median Plane been used in place of cephalic 



DIAGRAM OF A TRANSVERSE SECTION OF THE and caudal to express the rela- 



BODY, AND OF AN ORGAN, A. 



tion of an organ to the head and 



tail of an animal : cranial and caudal, nasal and caudal, proserial 

 and retroserial, oral and aboral. 



In describing the bones of the head and of the limbs of a cat, 

 we can use the extrinsic terms used in describing the corresponding 

 human bones ; the positions of these parts of the skeleton are practically 

 identical. 



(2) The terms cephalic and caudal are awkward in describing the 

 head itself, and no less so the terms dorsal and ventral. The heads 

 of all mammals may be assumed to be held in practically the same 

 position ; hence the terms upper and lower, anterior and posterior, 

 are sufficient. 



For greater exactness it is sometimes desirable to use additional 

 intrinsic terms ; as, the intracranial surface of a bone, for the sur- 

 face which shows on the inner surface of the cranial wall ; or the 

 nasal process of the maxillary bone, in place of the ascending 

 process. 



(3) The end of a limb bone near the attachment of the limb to the 



