716 



THE BLOOD-VASCULAR SYSTEM OF THE OX 



2. The ileo-caeco-colic artery ramifies on the right face of the spiral part of the 

 colon. It gives off the ileo-csecal artery, which divides into ileal and csecal arteries. 



3. The ramus coUateralis runs in the mesentery in a curve along the ventral 

 border of the coils of the colon. (This vessel is absent in the sheep.) 



4. The continuing trunk (Truncus intestinalis) of the anterior mesenteric 

 pursues a course in the mesentery corresponding to the series of mesenteric lymph 

 glands and is connected with the ramus coUateralis. 



The two preceding vessels are essentially the arteries of the small intestine, 

 which they supply with the exception of its initial and terminal parts. The ramus 

 coUateralis gives off no considerable branches in its course along the ventral border 

 of the coils of the colon, but on curving upward along the latter it anastomoses with 



Fig. 600. — Pelvic Arteries op Cow. 

 Part of the right wall of the uteru3 and vagina is removed and the cervix uteri is shown in sagittal section, a, 

 Aorta; b, utero-ovarian artery; b', ovarian, and b"j uterine branch of b; c, external iliac artery; d, right internal iliac 

 artery; e, common trunk of umbilical artery {e') and middle uterine artery (f) ; g, ilio-Iumbar artery; h, anterior gluteal 

 arteries; i, middle heemorrhoidal artery; k, posterior uterine artery; I, perineal artery; m, posterior gluteal artery; n, 

 obturator arteries; o, artery of clitoris; p, posterior mesenteric artery; r, anterior hgemorrhoidal artery; s, middle 

 sacral artery; 1, ovary; 2, apparent body of uterus, really apposed horns; 2', horn of uterus; 3, vagina; 4i neck of uterus; 

 4', external orifice of uterus (os uteri); 5, 5', broad ligaments, large part of right one removed; 6, urinary bladder; 7» 

 rectum; 8, sacrum; 9, symphysis pelvis. (After Zieger.) 



the continuing trunk of the anterior mesenteric artery and detaches numerous 

 branches to the small intestine which form series of superposed anastomotic arches. 

 It supplies, roughly speaking, about one-third of the small intestine and terminates 

 by joining the ileal artery. The continuing trunk gives off numerous branches 

 which also form arches and supply about the first two-thirds of the small intestine, 

 exclusive of the small part supplied by branches of the coeliac artery. Both arteries 

 give branches to the lymph glands.^ 



The posterior mesenteric artery arises from the aorta near its termination. It 

 is small and supplies branches to the terminal part of the colon and to the rectum 

 (A. cohca sinistra; A. haemorrhoidalis cranialis). 



' It is difficult to make the arrangement of these vessels clear in a brief textual description, 

 but a reference to the schematic figure will explain the main facts. 



