O F N A T U R A LH I S T O R Y. 45 ' 



culations, and ligaments. In the centre of each vertebra there is a 

 foramen, or hole, for the lodgement and continuation of the fpinal 

 marrow, which extends from the brain to the rump. From thefe 

 vertebrae the arched bones called libs proceed; and feven of them 

 join the breaft-bone on each fide, where they terminate in cartilages, 

 and form the cavity of the thorax, or chcft. This cavity contains 

 the heart and lungs ; and the oefophagus, or gullet, paffes through 

 it to reach the ftomach. The five lower ribs, with a number of 

 mufcles, form another cavity termed the abdomen, or belly, in which 

 are contained the ftomach, the bowels, the oinentum, or cawl, the 

 liver, the gall-bladder, the fpleen, the pancreas, and the kidneys. 

 The cheft and abdomen are feparated from each other by the dia- 

 phragm, or midriff. The lower part of this laft cavity contains the 

 bladder of urine, and the reftum, or termination of the inteftines. 

 Befide thefe, in females, the pelvis includes the uterus and its ap- 

 pendages. This part of the cavity is formed by the os facrum, or 

 termination of the back-bone, and the two offa innominata. 



The bones of the cranium and face are very numerous. They 

 are connected together by means of futures, articulations, and mem- 

 branes. The bones of the cranium include the brain, and its two 

 membranous coverings, called the pia and dura jnater^ and the me- 

 dulla oblongata, of which laft the fpinal marrow is- a prolongation. 

 The bones of the upper and under jaw form another cavity for the 

 reception of the tongue and organs of fpeech. 



The only remaining bones are thofe of the upper and lower ex- 

 tremities. The fhoulder and collar bones articulate with the top of 

 the arm and the breaft-bone. The arm-bone, or os humeri, is join- 

 ed to the two bones of the fore-arm, called ulna and radius, and 

 thefe laft to the bones of the carpus, or wrift, by means of articula- 

 tions 



