CIRCULATORY SYSTEM. 201 



detaclies twigs to the vesiculae seminales, but distributes its 

 ultimate ramifications to the prostates. 4. Divers branches, 

 anal and perineal, to the posterior portion of the rectum, anus, 

 and parts composing the perineum. 



The obturatok artery, the lowermost of the divisions of 

 the internal iliac, corresponds in the first part of its course to the 

 brim of the pelvis, in which "it is accompanied by the crural 

 nerve : it subsequently inclines upward to gain the posterior nook 

 of the foramen obturatorium vel magnum, and there gains exit 

 through the perforation in the obturator ligament. It now turns 

 round the branch of the ischium, and on the front of that bone 

 ends in division into the ischiatic, pubic, and internal pudic 

 arteries. Its branches are — 1. The arteria innoniinata, one of 

 very large dimensions, which comes off not far from its origin from 

 the iliac. This proceeds backward and outward, close under the 

 pelvic margin, crossing obliquely the external iliac artery and the 

 psoee and iliacus muscles, and dips deeply into the substance of 

 the haunch, wherein it sends branches downward to the rectus, 

 upward to the tensor vaginae. 2. Ramifications to the obturator 

 muscles and ligament, in passing through the foramen. Its 

 divisions or remaining branches are — 3. The ischiatic, which 

 turns down upon the back of the haunch, passing opposite to the 

 hip-joint, and distributes its branches to the triceps. 4. The pubic 

 runs backward along the branch of the ischium, and expends 

 itself in the large head of that muscle. 5. 2'he internal pudic 

 artery turns inward and backward, around the ischial arch to the 

 root of the penis, where it splits into two sets of branches, a. 

 One set penetrate and end in the crus penis, h. Two or three 

 branches belonging to the other set run further forward, and pierce 

 the fibrous case of the corpus cavernosum. c. One or two slender 

 branches of the same run along the dorsum penis, d. Another 

 accompanies the pudic nerve to the extremity of the organ. 

 e. Besides which there are sundry cutaneous twigs. 



The gluteal artery, the middlemost of the iliac divisions, 

 shortly after its origin leaves the pelvis through the hole in the 

 sacro-sciatic ligament, at the anterior nook of the notch, in com- 

 pany with the sciatic nerve, which runs behind it: immediately 

 that it has made its exit, it splits into two or three branches of 

 large size, whose ramifications are destined principally for the 

 gluteal muscles, though some descend to aid in the supply of the 

 posterior femoral muscles. 



The lateral sacral artery proceeds directly backward, 



along the side of the sacrum, to which being closely bound by 



cellular adhesion it necessarily takes the slight curve of that bone: 



having reached the coccyx, it splits into two long, slender, termi- 



u d 



