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the costal angle. Therefore it is not possible to exaggerate the action 

 of the recti by taking measurements on the dead body. On this 

 argument then I decided that the results of measurement of the 

 costal angle would be worthless if there were any great discrepancy 

 between the measurements of the clavicular angle before and after 

 death. There is always however the reservation that the angles are 

 very difficult to measure exactly to one degree and therefore it is 

 necessary to take a considerable number of observations from which 

 to obtain the averages. 



I have been able to examine post-mortem 40 individuals. They 

 included: 



29 males of ages ranging from 18 to 61. 



6 females „ „ „ 20 to 46. 



5 children „ „ „ 1 to 14. 



The post-mortems on v/onien and children are much more diffi- 

 cult to obtain than those on men. The observations made are tabu- 

 lated in Column B of the Appendix. 



The method of measuring the costal angle is as follows: — One 

 limb of a pair of short calipers is adjusted so that its point enters 

 the periosteum over the middle of the neck of the rib, while the 

 fork of the instrument lies on the cut end of the first costal cartilage. 

 The other limb of the calipers is then adjusted to the horizontal/ 

 (Fig. III). 



In these measurements also it is evident that both clavicular and 

 costal angles are liable to considerable individual variation. 



Taking the averages the following results are obtained: 



Adult Males 

 Adult Females 

 Children 



Clavicular angle = 30.3» 



Costal „ = 50.2'' 



Clavicular angle = 25.17'' 



Costal = 47.17« 



Clavicular angle = 24« 



Costal = 33« 



In comparing the results of measurement of the clavicular angle 

 in the living and the dead it is seen that the discrepancy is not 

 greater than can be accounted for by personal error. 



The measurements taken of the costal angle show it to increase 

 from birth to adult age in both sexes. They also show that the first 



