257 



in the umbilical and other arteries, longitudinal muscle fibres occur 

 in the adventitia. But with rare exceptions it is taught that the 

 media proper is composed wholly of transversely disposed muscular 

 elements. We have been unable to obtain the origmal of Prof. Karl 

 V. Bardeleben's (o) observations so long ago as 1878, and so are unable 

 to state precisely the arrangement of the oblique muscular fibres 

 noted by him. I trust that he will be so good as to add a short note 

 appendix to this communication recalling these early observations. 

 Among later writers Schäfer (6) notes that oblique and occasional 



*V> 



cv :>^-^-^Cir^=?=ÄÄ 



b — 



Fig. 1. Section from a Popliteal artery showiug an oblique bundle situated in 

 the deeper portion of the Media, near the Intinia. 

 (a) Intinia. (b) Media, (c) Oblique bundle. 



longitudinal fibres are to be encountered in certain situations such as 

 the lower reaches of the iliac, and that fibres of this order occur also 

 at the origins of the abdominal branches of the aorta. In like manner 

 Stirling (7) states that there are longitudinal fibres in the media of 

 the descending aorta, the common iliac, and the popliteal arteries. 

 Nothing of these last two authors suggests the existence of definite 

 and constant bundles of longitudinal and oblique fibres in the media. 

 The study of a veiy great number of Sections from different 



Anat. Anz. Bd. 44. Aufsätze. 17 



