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Show 366 Ml!. K. B, BEDDARD ON THE [Feb. 16, The adrenal portal vessels are more numerous than those of the right adrenal body. The anterior, made by the union of two main branches, each of which recovers blood from three intercostal spaces, enters the adrenal body in front of the anterior spermatic artery; the second, gathering blood from three intercostal intervals, lies between the two spermatic arteries. Renal Arteries.-In noting the most important fact about the renal arteries, namely, that there is only one to each kidney, it must be borne in mind that the kidneys are extraordinarily small. They measure about 2| inches in length, and the posterior is situated a foot away from the vent. Each renal artery enters the kidney at its anterior end, and between the two renal arteries arises the inferior mesenteric, which is much more important than any of the slender intestinal arteries which follow. LACHESIS GRAMIXEUS. The anterior vertebral is short in this species, only reaching to a point 14 inches from the heart (and 6 inches from the snout) before plunging into the parietes. It gives off but a single intercostal branch, which is not far from its origin. The light aortic arch itself is much more slender than the left; it gives off two intercostal arteries before joining the left aorta. The disproportion between the right and left aorta is so very marked that the former when it joins the latter is not larger than one of the intercostals. After the junction of the aortae to the posterior end of the trunk there are only 22 intercostals ; as is the rule, they become more numerous posteriorly. For example, the region lying between the junction of the aorta? and the origin of the superior mesenteric only gives off six of these arteries. Another peculiarity of this species is the fact that all the intercostal arteries, without a single exception, enter the parietes in the middle line. This is associated with, though it can hardly be caused by, two particularly projecting bands of muscle which lie one on either side of the dorsal median line. That the strong development of these muscular bands has no special relation to the accurately median entrance of the intercostal arteries appears to be shown by the relation to the same of the intercostal portal veins. Intercostal Veins.- There are six of these veins in front of the point of origin of the superior mesenteric artery ; but they have no special correspondence to the six intercostal arteries which arise in the same area. All of these veins emerge from the parietes to the left of the longitudinal bands of muscle referred to. Just at the level of the superior mesenteric artery a stout portal vein emerges from the right side; thereafter follow two veins, also emerging from the right side. The remainder of these vessels (six in number) arise again on the left side of the dorsal median line. The liver commences very high up in the body. Its apex is |