OCR Text |
Show 1904.] CIRCULATORY SYSTEM IX THE OPUIDIA. 351 its anterior boundary, this artery divides into three. The outer one bends round the anterior end of the kidney and, after giving off two small branches to the kidney-substance, goes to the oviduct ; the second branch crosses the kidney, gives off a branch to the kidney-substance, and then passes on to the oviduct; the third branch forms the longitudinal renal artery which runs along the inner margin of that organ. The ureter and the afferent renal vein which lie on the flat ventral surface of the kidney receive a branch from a vessel which arises from the longitudinal renal trunk between its first two affluents from the aorta. The second renal artery divides into two branches just before reaching the edge of the kidney which form the longitudinal renal vessel; the anterior branch gives oft" a vessel which crosses the kidney, and, after giving off a branch to the longitudinal trunk running down the ureter, Text-fig. 69. Spermatic and neighbouring arteries of Tropidonotus fasciatus. Ao., aorta ; F.B., fat-body arteries ; I.M., inferior mesenteric artery ; Int., intestinal arteries; JB1, renal arteries of right kidney ; B2, do. of left kidney; Sp. 2, spermatic artery of left testis; Sr., suprarenal body; Sr.', suprarenal portal veins (left white); T, right testis. becomes an oviducal artery ; some little way before reaching the oviduct it sends back two branches to the ureter. The third renal artery as well as the fourth supply the kidney-substance, the longitudinal renal artery, the ureter, and the oviduct. A little way beyond the end of the kidney the ureter receives a special branch from the aorta. Beyond this, again, a special branch supplies the oviduct. The left kidney is supplied by arteries whose arrangement is much that of those of the opposite kidney. There are four of them altogether. The first artery is, as has been also mentioned elsewhere, mainly an oviducal artery. Arrived at the kidney this vessel emits a strong branch which is the beginning of the longitudinal artery of the kidney ; a little farther on, as it curves round the end of the kidney, it gives off one or two small branches which plunge into the substance of the kidney. The second renal artery arises from the aorta behind the third renal artery of the opposite kidney. It is purely renal in distribution and gives off no branch to the oviduct. The third and |