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Show 348 MR. F. E. BEDDARD OX THE [Feb. 16, two branches, just at its origin, in fact, from the aorta, a moderately short branch is given off which very soon divides into two, one running to the spleen, the other to the ovary. In the male Tropidonotus fasciatus this branch was entirely absent. The inferior mesenteric springs from the aorta in both sexes close to the second gonad artery, in front of it in the male, behind it in the female. There are 4 well-developed intestinal arteries in the female, of which the last supplies the rectum; beyond this are a few of less importance. Ovarian and Oviducal Arteries.-There is no independent artery to the anterior ovary; it gets it blood-supply from arteries which also supply the oviduct; and from the same branches arise twigs for the supply of the fat-bodies. As is the case with other organs, a longitudinal system of blood-vessels is developed, which are fed by branches of the aorta. A longitudinal artery runs along Text-fig. 68. Ovarian and oviducal arteries of one side of the body in Tropidonotus fasciatus. Ao., aorta ; F.B., fat-body artery; Od., oviducal arteries ; Ov., ovarian arteries; Sr. V., suprarenal veins (left white), suprarenal body shaded. the ovary and another of greater calibre along the oviduct. The two are in communication by transverse branches. Of these branches I have counted 7, the last four being the larger and corresponding, together with branches arising behind the ovary, to that section of the oviduct which contained no less than 10 mature ova. The middle artery of the seven is much the largest and is a direct continuation of the artery arising from the aorta, which in other Ophidia supplies mainly, if not exclusively, the gonad. Here, as will have been seen, the main branch is to the oviduct. The longitudinal ovarian vessel is also in communication by |