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Show 5 1 0 MR. F. E. BEDDARD OX THE VASCULAR AND [M a y 1, In Boa constrictor the left vein had only two of these : I counted four joining the right renal afferent. I did not count these veins in Boa diviniloqua. In the latter species (of which one example was in a particularly good condition for observing the point) t le renal afferent, as in other Boidse*, extends beyond the kidney and forms a delicate vein running up to the testis. This is doubtless the posterior cardinal. Epigastric Vein.-I did not note the number of branches which connect in Boa diviniloqua the anterior abdominal with the epigastric vein. In Boa constrictor I was able to observe that alf these branches connect the epigastric vein with the left larger anterior abdominal. I could find no branches running between the smaller right anterior abdominal and the median single epigastric vein. This vein appeared to be concerned only with "the fat-body. Several branches, however, join the anterior abdominal and the epigastric after the former has become a single vessel by the union of the right and left halves. Posteriorly to this point there were in all about eight transverse vessels uniting the left anterior abdominal and the epigastric. The epigastric, I may take this opportunity of remarking, is one of the most constant veins in the Ophidia in its position, form, and relations with other veins. It appears to be nearly always single. In the case of Lioheterodon madagascariensis, however, a specimen which I dissected showed an epigastric vein constantly alternating between the single and double condition, like the dorsal vessel in certain Earthworms. As is so usual in the Ophidia, a considerable parietal vein flows into the afferent renal shortly before the latter reaches the kidney. At the anterior end of each kidney there is another such vein ; and a careful dissection of the same shows that it does not open into the kidney-substance or into the efferent renal, but into the very slender forward prolongation of the afferent renal. This vein, the posterior cardinal, is traceable, as already mentioned, to a little way in front of the testis. In the neighbourhood of each testis the vein receives the Suprarenal Portal Veins.-Of these veins (text-fig. 90, p. 511) 1 counted three separate trunks on the left side; two of these reached the cardinal in the region of the corresponding testis; the third vein lay further back, it emerged from the parietes, and joined the cardinal some little way behind the left testis. On the right side of the body there were only two of these parieto-suprarenal veins. They reached the posterior cardinal of their side of the body in the region of the corresponding testis. In describing certain points in the anatomy of the Anacondaf, I recorded the presence of an extensive vein running along the body-wall on both sides of and near to the spinal column in the region of the kidney. This vessel connects the affluents of the * Cf. Beddard, " Contributions to the Anatomy of the Ophidia," P. Z. S. 1906, vol. i. p. 28. f P. Z. S. 1906, vol. i. p. 23, text-figs. 6, 7. |