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Show 1903.] ANATOMY OF THE HAMADRYAD SNAKE. 321 bile-ducts emerge from the rete and pursue a long course (long as compared with the plexus region) through the pancreas to the intestine. Arrived at the intestine they do not debouch directly into its lumen by five orifices, but open separately, or nearly so, into a thick-walled diverticulum of the gut, which itself communicates with the gut by an orifice not wider than one of the separate bile-ducts. I have noticed a similar diverticulum, which receives both cystic; and hepatic ducts, in Westerman's Cassowary. As compared with the Cobra*, which I have also examined, the bile-ducts of Ophiophagus are more numerous and more complex in their intercommunications. The hepatic duct, for example, is single, though it communicates with more than one of the cystic ducts. The gall-bladder itself has not so long a common cystic duct as that which characterises Ophiophagus. I do not think that a more minute description of the cystic network in the two types is useful at present; but I may observe that sketches of the gall-bladder published by other anatomists, and a few made by myself, indicate that the general plan of the cystic rete is not without use in distinguishing and comparing various genera of serpents. Again, the Cobra has a. testis proportionately longer than that of the Hamadryad and differently situated. The anterior testis is 21 inches long and its anterior border is 11 inches from the liver ; its posterior border is a long way in front of the kidney. In Ophiophagus bungarus the anterior testis abuts so closely upon the anterior kidney that the two organs are only just disconnected ; while the spermatic artery, influenced, so to speak, by this near approximation, sends a branch to the kidney before entering the testis. The anterior end of the testis is, moreover, 22 inches away from the end of the liver, and it measures only 1| inches in length though very much plumper than the corresponding testis of the Cobra. In estimating these facts it must be borne in mind that the Hamadryad measured 93 inches from tip of snout to vent, and the Cobra 51 inches. More possibly, but still to m y mind not certainly, associated with difference of size is the fact that the Hamadryad possesses six gastric arteries as against three in the case of the Cobra. I recognise-it may be explained-as gastric arteries those vessels which arise from the aorta after the posterior end of the liver and supply the stomach only. In the Ophidia generally there are two Carotid arteries, both of which spring near together from the right aortic arch. The left-hand artery is, I believe, always the largest, and extends right up the neck as far as the head, giving off branches along its course to the gullet and windpipe. The second and smaller of the two Carotids is, as a rule, of much smaller calibre, and in the distribution of its twigs is hardly more than a thyroidean artery. In Ophiophagus bungarus these conditions obtain, and the artery in question does not extend..up. the neck very much beyond the * Bronn's 'Thierreich,' Kept., Bd. vi. pt. iii. pi. cxxx. fig-. 2. PROC. ZOOL. Soc-1903, VOL. II. No. XXI. 21 |