Measurements of ribs 



in 



Mammal s 



by 

 R. J. Anderson 



ill G al way. 



(With PI. II. U. III.) 



I give here the breadths of the ribs in several mammals. The 

 measurements are in millimetres. The term radial breadth is used 

 where the principal surfaces of the ribs look forwards and backwards. 

 The anterior surfaces were measured. The term tangential breadth 

 is used to indicate the breadth of the outer surface, where this is 

 the principal surface. The length of the vertebral rib was taken from 

 the tubercle to the lower end. The length of the sternal rib or car- 

 tilage from the end of the vertebral rib to the sternum is given. 

 Everyone knows that the prominent features of some ribs are the broad 

 outer and inner surfaces, of others the broad anterior and posterior 

 surfaces. The surfaces that are anterior and posterior above may 

 become narrow below whilst tlie borders may widen into surfaces. 

 In some animals the i)Ostcrior surface turns out as we trace the rib 

 from the vertebral to the sternal end. In some forms the ribs have a 

 marked increase in the tangential breadth near the tubercle in others 

 the increase is most decided near the lower end. 



*) The author desires to express his thanks to Professor Trincbese of Naples who 

 gave him peniiisHion to exuniiiiu his skeletons and to his assistants for their kindness 

 and courtesy. 



