toes, the PHALANGES. The bones in the hind limb are 

 somewhat similar to those in the front or fore limbs. 

 The upper, or thigh bone, is the largest and is called 

 the Femur. The bones of the lower limb are the TiBIA, 

 or shin bone, and the FlBULA, which is the outer bone. 

 The latter is not well developed in horses and rumi- 

 nants and exists in these as a splint fused to the Tibia. 



The foot bones of the hind limb are also similar 

 to those of the fore-foot, and the three parts are called 

 the Tarsus, Metatarsus and Phalanges. The upper 

 bones of the Tarsus are peculiarly modified to form the 

 Ankle Joint and the Heel. 



An animal may walk with the entire sole of the 

 foot in contact with the ground, as do Raccoons and 

 Bears. Such an animal is called PLANTIGRADE. When 

 it walks on its toes, like the dog or cat, it is called a 

 DiGITIGRADE animal. By studying the manner of walk- 

 ing in the various animals, one can soon learn to recog- 

 nize tracks left in mud or snow. Trailing animals is 

 real sport. Fig (7) shows the tracks of some of the 

 more common mammals. 



This brief description of the Mammalian skeleton 

 is far from complete, but it is the wish of the writer to 

 avoid the inclusion of a long list of technical terms and, 

 too, space would not permit of a full description. This 

 much has been given to show the general structural 

 features of mammals. The reader may learn the other 

 structures and their arrangement from the labeled 

 skeleton on plate (6). 



■>:>C 50 >«<- 



