The descending branch passes inferiorly, supplying the lower part of the descending colon, and anastomoses with the first sigmoid artery.
The sigmoid arteries consist of two to four branches, which descend to the left, in the sigmoid mesocolon, to supply the lowest part of the descending colon and the sigmoid colon (Fig. 4.128). These branches anastomose superiorly with branches from the left colic artery and inferiorly with branches from the superior rectal artery.