lO DISSECTION OF THii CAT 



C— Ribs. 



The Ribs form the bony framework of the 

 thorax. There are thirteen pairs, articulating dor- 

 sally with the vertebral column. The nine an-' 

 terior pairs or true ribs are connected with the 

 sternum by costal cartilages. The four posterior 

 pairs ox false ribs are not united to the sternum. 

 (Plate I., J.) 



D. — Sternum. 



The Sternum is the chain of bones forming the 

 ventral support of the cartilages of the ribs. It 

 consists of eight or nine bones (sternebrae), of 

 which the most anterior is the manubrium. Pos- 

 teriorly the sternum ends in the ensiform carti- 

 '*'* ," which is more or less expanded and extends 

 Ifeei/ backward. (Plate I., k.) 



APPENDICULAR SKELETON. 



A. — Shoulder-girdle and Fore-leg. 



1. The Clavicle is the small bone which does not 

 articulate with any of the bones of the body, but 

 is imbedded in the muscles of the anterior part of 

 the shoulder. (Plate I., l.) 



2. The Scapula or shoulder-blade is the triangu- 

 lar bone which lies against the side of the thorax. 

 Its dorsal edge is the vertebral margin, its ventral 

 edge is the axillary margin. Its outer side is 

 divided by a longitudinal ridge of bone, the spine. 



