PRINCIPLES OF VETERINARY SURGERY 189 



size. The flow of blood is always more copious. It is dis- 

 ting-uished by the scarlet color of the blood and the spurting 

 of the jet with each beat of the heart. Its most common 

 cause is traumatism, but serious and fatal arterial hsem- 

 orrhages may result from rupture of diseased vessel walls. 

 The most common causes of dissolution of arteries are en- 

 croaching neoplasms and abscesses. Chronic diseases of the 

 arteries are somewhat rare in animals. Rupture of the 

 coronary artery may occur from fatty degeneration of its 

 coats, and aneurisms of parasitic origin sometimes cause 

 fatal haemorrhages from the mesenteric arteries, but even 

 these events are not of very common occurrence. 



The arterial haemorrhages of accidental origin may be 

 divided into three classes : The fatal, the serious and the 

 trivial. 



Fatal Haemorrhages supervene after solutions in the 

 continuity of the aortas, the iliacs, the femorals, the carotids, 

 the external thoracics, the external carotids, the occipitals 

 and the brachials. The radials and the tibials also give fatal 

 haemorrhages, although occasionally these may be con- 

 trolled before fatal bleeding- ensues. As regards the others, 

 a division of their walls is generally fatal, owing to the diffi- 

 culty of coping with the situation in time to arrest the flow. 



Serious Haemorrhages occur from the metatarsals, the 

 metacarpals, the glosso-facials, the palatines, the spheno- 

 paJatines, the superior cervicals, the inferior cervicals, the 

 spermatics, the mammaries, the external pudics, the internal 

 pudics, the- middle coccygeal, and the intercostals. Often 

 unnamed arteries that serve as the nutrient vessels of tu- 

 mors give very serious haemorrhages. Such vessels en- 

 large to accommodate the growing neoplasm, and being 

 anatomically defective, they lead to more copious bleeding 

 of the normal vessels of the same size. 



All of these arteries, although placed second in the scale 



