Luschkcts Gland 355 



may be avoided. The arteria sigmoidea, from the inferior mesenteric, 

 communicates with the colica sinistra above and with the superior 

 haemorrhoidal below. 



The lumbar arteries, four on each side, run outwards, like the 

 intercostal arteries. They pass beneath the psoas and behind the 

 quadratus lumborum, and then between the inner oblique and the 

 transverse muscles. They anastomose with branches of the internal 

 mammary, deep epigastric, lower intercostal, ilio-lumbar, and deep 

 circumflex iliac arteries. They also give branches (spinal) along the 

 lumbar nerves, which supply the cauda equina, spinal cord, and the 

 vertebral periosteum ; and a branch (dorsal) which runs back between 

 the transverse processes for the erector spinas, and for the integument 

 of the loin. 



The middle sacral passes from the bifurcation of the aorta down 

 the middle of the fifth lumbar vertebra, and the sacrum and coccyx ; 

 it gives branches to the anterior sacral foramina and to the rectum, 

 which latter anastomose with other haemorrhoidal arteries. On either 

 side the sacra media anastomoses with the lateral sacral branches, 

 and at the tip of the coccyx it supplies Luschka's gland. 



The coccygeal, or Luschka's gland, at the tip of the coccyx, is a 

 pisiform tuft of small vessels derived from the ending of the sacra 

 media. It is surrounded by granular cells, and by a fibrous coat 

 which sends fine processes into the interior. Nerve-filaments enter it 

 from the ends of the neighbouring sympathetic chains. The gland is 

 of surgical importance in that it may be the starting point of certain 

 coccygeal, sacral, and pelvic tumours of infant life. 



THE INFERIOR VENA CAVA 



The inferior vena cava begins at the right side of the fifth lumbar 

 vertebra by the confluence of the common iliac veins. It ascends upon 

 the right side of the aorta, being separated from it above by the right 

 cms ; it deeply notches the back of the liver (where it receives the 

 hepatic veins), and, passing between the right and central leaflets of the 

 phrenic tendon, opens at once into the right auricle. The right renal 

 and lumbar arteries cross between it and the vertebrae. In front 

 of it are coils of small intestine and mesentery ; the right spermatic 

 artery ; transverse duodenum, pancreas, portal vein, and right lobe of 

 liver. To the right side are the kidney, ureter, psoas, and ascending 

 colon. 



Its tributaries are the lumbar, which closely correspond in distribu- 

 tion with the lumbar arteries. The left lumbar veins are the longer, 

 as they have to pass beneath the aorta. The upper lumbar veins com- 

 municate with a vena azygos. 



The right spermatic and supra-renal and lower phrenic veins end 



A A2 



