ZOOLOGICAL POSITION AND STRUCTURE 9 



processes arising from the frontal bones of the 

 skull. The BovidcB are further characterised by 

 the absence of upper front teeth, or incisors, the 

 place of which is taken by a hard callous pad, 

 against which bite the three pairs of lower incisors 

 and the single pair of lower canines, or tusks, which 

 collectively form a semicircular series of four pairs 

 of similar teeth. This peculiarity is correlated with 



Stomach of a Sheep, partially cut open to show 

 Internal Structure 



a, oesophagus, or gullet ; ru, rumen, or paunch ; rtt, reticulum, or 

 honeycomb; ps, psalterium, or manyplies ; ab, abomasum; 

 py, pylorus ; </«, duodenum, or commencement of the small 

 intestine. 



a characteristic structure of the cheek-teeth, the 

 last three pairs of which, technically known as 

 molars, carry on their crowns four columns ; the two 

 innermost of these in the upper jaw and the two 

 outer in the lower, having a distinctly crescent-like 

 form, whence this type of dentition is known as 

 selenodont, from the Greek selene, the crescent 

 moon, and odous (genetive odontos), a tooth. But 

 this is by no means all, for this very remarkable 



