| OCR Text |
Show 1004.] CIRCULATORY SYSTEM IN T H E OPHIDIA. 357 two trunks, of which one runs straight forward to the further side of the stomach, while the other branch immediately divides into two main branches which supply the nearer of the two longitudinal gastric arteries; these also give off arteries to the fat-body. Arteries 3 and 5 cross the stomach and pass at once to the further of the two longitudinal arteries; there is no branch to the nearer. The 4th and 6th are like the 1st and 2nd, in that they supply both the gastric longitudinal vessels. The 6th artery is not markedly larger than the 4th. The gastric branch of the superior mesenteric divides into two trunks, each of which supplies one of the two longitudinal trunks of the stomach. It is to be noted that the spleen, gall-bladder, <kc. are not supplied with blood from the last gastric artery, but only from the superior mesenteric. This contrasts wTith the condition observable in some other snakes. Spermatic Arteries.-There is but a single spermatic artery to each testis. The first of these is the first visceral branch of the aorta after the superior mesenteric. It reaches the testis at its Text-fig. 72. Bight testis of Ophiophagus and its blood-supply. Ac, aorta; F.B., fat-body artery; I.C., intercostal artery; Int., intestinal artery; K., kidney; Sp.A., spermatic artery; Sr.p., suprarenal portal vein ; T., testis ; V.c.i., vena cava. posterior end, where it is nearly in contact with the kidney. At this point the spermatic artery gives off a branch to the kidney. The spermatic artery runs along the kidney anteriorly on the opposite side to the vena cava, giving off branches to its substance (see text-fig. 72). It also gives off two branches, which supply adjacent viscera: firstly, a stouter branch to the fat-body; secondly, a more slender branch which supplies both fat-body and intestine. Close to the spermatic artery runs a portal vessel to the suprarenal. It emerges from the parietal on the right of the middle line by three roots. The posterior testis, which is considerably the smaller, has also one spermatic artery. This gives a branch to the intestine before it reaches the testis, and later two branches |
