6, Lower sesamoid or navicular 13, The coronary cushion, bone.
The aortic trunk is very short, sends off the coronary arteries and then the left aorta brachiocephalica, while the rest divides into the right brachiocephalic and the aorta descendens.
A thickened ring encircling the upper part, called coronary cushion (13) and the sole (15), are covered with numerous thickly-set 17 papillae or villi, and take the greatest share in the formation of the hoof; the intermediate part constituting the front and side of the foot (14), corresponding with the wall of the hoof, is covered with parallel, fine longitudinal laminae, which fit into corresponding depressions in the inner side of the horny hoof.
The gift of "coronary gold" (aurum coronarium), presented to the emperor on certain occasions, was entirely remitted in the case of Italy, and partly in the case of the provinces.
The systole is not altered in length, but the diastole is very much prolonged, and since this is the period not only of cardiac rest but also of cardiac "feeding" - the coronary vessels being compressed and occluded during systole - the result is greatly to benefit the nutrition of the cardiac muscle.