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Show 1904.] ANATOMY OF THE LACERTILIA. 9 left was rather longer than the right, and the reverse was the case in another specimen. I presume that these veins are the posterior cardinals ; they lie exactly in the same straight line as the two azygos veins anteriorly, which are admitted to be the anterior section of the posterior cardinals. It receives branches from between the ribs running superficially over the musculature. These differ on the two sides of the body in the individual where they were best shown, a large specimen in which I describe later the oviducal veins. On the right side, close to the point where the posterior vertebral loses itself in the parietes, it receives two thinnish veins from the parietes superficially. Further back, and close to the anterior end of the suprarenal body, a thicker vein, fed by two branches which run backwards and forwards respectively along the parietes, enters it. On the left side there is only one anterior vein debouching into .the posterior vertebral. The corresponding vein to the thicker posterior vein on the right side opens directly into the suprarenal body, as explained later and as illustrated in the figure to which reference has already been made. I mention later that in Pygopus there is a vein obviously corresponding to the posterior vertebral. There is also, as I have described, a similar vein in Iguana * which arises from the parietes close to the median side on the left, and forms one of the afferent suprarenal vessels. In Iguana, as in most Lizards, the suprarenal body lies a long way in front of the kidney, hence the absence in that form of a connection between the posterior vertebral and the kidney. In a more fully mature individual of large size, which I owe to the kindness of Mr. J. F. Ochs, F.Z.S., the veins of the kidney region were very successfully injected, and enable me to describe, which was impossible in the other specimen, the oviducal veins. There was a slight difference on the two sides of the bod y; on the left side three oviducal veins reach the posterior vertebral vein in front of the kidney, one crossing the suprarenal body to do so. In the region of the kidney itself three oviducal veins reach the afferent renal in front of the anterior abdominal, and at least two behind it. On the right side, the most anterior oviducal vein takes up, before reaching the posterior vertebral vein, a vein from the dorsal parietes anterior to, but in the same straight line with, the posterior vertebral at the point where it plunges into the thickness of the parietes. Some of the oviducal veins take up a branch from the suprarenal body before joining the posterior vertebral; in other cases the efferent suprarenal veins open directly into the posterior vertebral. A remarkable fact about the oviducal veins is the anterior termination of the longitudinal vein running along the entire oviduct into which they open. This vein could be readily traced * hoc. cit. p. 413. |