To this class belongs the occlusion of the vessel arising from different varieties of coagulation of blood.

A. Occlusion Of An Inflamed Artery

According to our definition of arteritis, this condition can only affect arteries in which the circular fibrous coat is only subordinately developed. (See p. 193).

B. Occlusion Of An Artery Arising From A Coagulation Of The Blood

Occlusion Of An Artery Arising From A Coagulation Of The Blood, depending upon an internal cause, such as a blood-disease. - To this class belong Velpeau's case of closure of the aorta, from the third lumbar vertebra downwards, with a part of the iliac artery, owing to a coagulation of a cancerous character in an individual exhibiting cancerous cachexia, and undoubtedly also the cases of occlusion of the thoracic and abdominal aorta observed by Schleskiger and Barth. Occlusion arising from arteritis, and especially the form above described, is very rare when compared with the frequency of occlusion of the veins.