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Show 1904.] ANATOMY OF THE LACERTILIA. 11 It receives minute branches from the parietes throughout its whole course to the liver. Contrary to what is found in most Lizards, the portal vein joins the anterior abdominal at a long distance from the liver, in fact about halfway between the origin and termination of the vein. The system of veins of the bladder is connected with the anterior abdominal. A median vessel leaves the bladder anteriorly and joins the undivided region of the anterior abdominal. Another branch (? on each side) runs from the hinder part of the bladder to the right anterior abdominal behind the entrance of the fat-body veins. Suprarenal Portal Veins.-As a general rule, there appears to be no distinct suprarenal portal system : the suprarenal body receives branches from the posterior vertebral vein given off along the course of the latter, which have been already referred to. But on one side of one individual there were separate suprarenal portals. This is illustrated in the accompanying drawing (text-fig. 1, p. 8). On the right side of /the body two veins collecting blood from the parietes, instead of joining the posterior vertebral vein, pour their contents directly into the suprarenal body of that side. The more usual absence of an independent suprarenal system is to be explained, as I imagine, by the fact that the suprarenal bodies are closer to the kidneys than they are in some other Lizards, such as Iguana, where the suprarenal system is quite independent. Dorsal Aorta and its Branches.- The subclavian arteries (text-fig. 2, p. 12) spring from the right aortic arch, and I observed a difference in two specimens dissected as to their mode of origin. In the one the two arteries arose independently-that of the right side being anterior to the left. In the other specimen the two subclavians sprang from a common trunk. Both subclavians give off vessels to the parietes (shown in the drawing referred to). The right-hand artery gives off a single trunk which immediately divides into two, one going to the parietes, the other supplying the oesophagus and running there in company with a branch of the azygos vein of that side. The left subclavian gives two branches to the parietes following each other, which are not paired tubes as is the case with the intercostals given off from the aorta itself. The right aorta gives off two pairs of intercostals before it joins the left. The left aorta, on the other hand, gives origin to gastric trunks, of which I counted three before the junction of the two aortse. The gastric trunks of the common aorta arise alternately from either side of that artery, and are disposed in pairs supplying naturally each side of the stomach. There are eight of these arranged in four pairs anterior to the origin of the mesenteries. The intercostal arteries are for the most part strictly paired, the two arteries for a given vertebra arising exactly side by side. Occasionally, however, there is an irregularity, one of the two arteries arising a little in front of the other. As is the case with most Lizards, the gastrosplenic artery |