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THE SACRAL PART OF THE GANGLIATED CORD. 669 
of the lumbar vessels, It is connected with the thoracic portion of the cord by an 
attenuated commissural cord, which either pierces or passes behind the diaphragm. 
It is continuous below with the sacral portion of the cord by a commissure, which 
passes behind the common. iliac 
artery. It is jommed by medul- 
lated fibres (white rami communi- 
eantes) from the first two lumbar 
spinal nerves, and it contains as 
well medullated fibres continued 
down from the lower part of the 
thoracic ganghated cord, and 
derived from the visceral branches 
(white rami communicantes) of the 
lower thoracic nerves. This part 
of the gangliated cord is char- 
acterised by great irregularity in 
the number of the ganglia. They 
are usually four in number, but 
there are frequently more (up 
to eight); and in extreme cases 
fusion may occur to such an 
extent that the separation of 
individual ganglia becomes impos- 
sible. 
White rami communicantes. — 
The first two (or three) lumbar 
spinal nerves possess visceral 
branches which form white rami 
communicantes joining the upper 
lumbar gangha or the ganghated 
cord. These nerves form the lower 
limit of the thoracic-lumbar visceral 
branches of the spinal nerves. 
They comprise vaso-motor fibres 
(for the genital organs), and motor 
fibres for the bladder and uterus. Fic. 480.—THE LUMBAR PorRTION OF THE SYMPATHETIC 
Central Communicating GANGLIATED CORD AND LUMBAR PLEXUs. 
Branches.—Gray rami communi- 1.11, 1.12, L.1, L.2, 1.3, L.4, L.5, Anterior primary divisions 
cantes pass from the gangliated of spinal nerves, with white and gray rami communicantes. 
cord to the anterior primarv divi- Sy, Sympathetic gangliated cord; Va, Vagus nerve; G.S, Great 
P Ne splanchnic nerve, jcining semilunar ganglion ; 8.R.C, Supra- 
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rc 
Ne WAM iictiaa UUiMd AA Lit deans VF 
AW oe cre oan lh a 
sions of the lumbar nerves in an renal capsule and plexus; R.Pl, Renal plexus; Ao.PI, 
irregular manner. One ramus may Aortic plexus ; 8.M, Superior mesenteric plexus; I.M, 
ex : ; Inferior mesenteric plexus ; Hy.Pl, Hypogastric plexus ; 
divide re AS ae supply branches to Q, Nerves to quadratus lumborum ; I.H, Hio-hypogastric 
two adjacent spinal nerves; or a nerve ; I.I, Ilio-inguinal nerve ; G.C, Genito-crural nerve ; 
spinal nerve may be joined by E.C, External cutaneous nerve ; A.C, Anterior crural nerve ; 
two to five separate oray rami Acc.Obt, Accessory obturator nerve ; Obt, Obturator nerve ; 
5 4, 5, Lumbo-sacral cord. 
from the gangliated cord. 
The gray rami course, along with the white rami, beneath the origin of the 
psoas magnus muscle, and over the bodies of the vertebrae. Gray rami sometimes 
pierce the fibres of the muscle. 
Peripheral Branches of Distribution—From the lumbar ganghated cord 
numbers of small branches arise irregularly, and pass inwards to supply the 
abdominal aorta, reinforcing the aortic plexus (from the solar plexus). 
THE SACRAL PART OF THE GANGLIATED CORD. 
The sacral part of the gangliated cord, like the cervical and lower lumbar 
portions of this system, receives no white rami communicantes from the spinal 
nerves. ‘The visceral branches (pelvic splanchnic) of the third, and usually, also, 
