258 



arteries throughout the body, prepared by the method above described 

 demonstrates that in general the older teaching is correct: the ex- 

 panded media is formed of concentric, circularly disposed muscle fibres. 



Here it deserves note that according to my experience the different 

 coats and their component cells are best differentiated by the employ- 

 ment of the following method. 



The study of a very great number of sections from different 

 arteries throughout the body, prepared by the method above des- 



"r .'Ä^r 



\^'^. 



^^a,^ iyjt J 





Fig. 2. Section from a Iliac artery showing an oblique bundle near the ex- 

 ternal surface of the media. 



{a) Intima. (b) Media, (c) Oblique bundle. 



cribed^) demonstrates that in general the older teaching is correct: 

 the expanded media is formed of concentric, circularly disposed 

 muscle fibres. 



1) Here it deserves note that according to my experience the different coats 

 and their component cells are best differentiated by the employment of the follow- 

 ing method: 



The sections are immersed from 12 to 24 hours in a one per cent solution of 

 Weigert's elastic tissue stain in Orth's "Discharging fluid". This stains the elastic 

 tissue a deep black, leaving the remaining tissue colorless. The sections are then 

 treated with haematoxylin and eosin in the usual way. 



