717 



Papers cited. 



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'94. — — Materials for the Study of Variation. London, 1894. 



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Nachdruck verboten. 



An Abnormal Iliac Vein in a Cat (Felis domestica). 



By Aaron L. Treadwell, Oxford, Ohio. Ü. S. A. 

 With one Figure, 



In a cat, dissected some time ago, was found an abnormality of 

 the vascular system, the nature of which will be readily seen by a 

 glance at the accompanying diagram. 



The internal iliac artery, leaving its condition of parallelism with 

 the internal iliac vein, plunges directly through the latter and continues 

 its course down the leg dorsal, instead of ventral, to that vein. The 

 opening is at the point where the right internal iliac vein would 

 naturally be given off, and at first sight seems to have been formed 

 by a reunion of that vein with the main vessel. I think however, 

 that the right iliac comes off farther down, at the point indicated 

 in the diagram. Unfortunately, these lower branches had been cut 

 before my attention was called to the abnormality, and their distribution, 

 which would have given certain evidence, was impossible to follow. 

 This opening seems to me to be an entirely new formation, to be referred 



