ABDOMEN AND PELVIS 515 



(b) Coeliac (plexus [lymphaticus] coeliacus}. 



(c) Lumbar (plexus [lymphaticus] lumbalis). 



(d) Aortic (plexus [lymphaticus] aorticus). 



Azygos and Hemiazygos Veins (V. azygos and V. hemiazygos). 



Study the abdominal tributaries of these veins. (Cf. Spalte- 

 holz, Fig. 495.) Examine especially the ascending lumbar vein 

 (V. lumbalis ascendens). 



NEEVES IN THE ABDOMEN. 



Abdominal Part of Sympathetic Trunk (Truncus sympathicus, pars 

 abdominalis) . (Vide Toldt, Fig. 1327.) 



Study the position of the truncus sympathicus in the abdo- 

 men. Determine its relation to the lumbar vessels and inferior 

 vena cava. Examine the lumbar ganglia (ganglia lumbalia). 

 Whither do the lateral and medial branches from these ganglia 

 go! Review the general disposition of the systema nervorum 

 sympathicum. What are the rami communicanles, and in what 

 relation do they stand to the spinal nerves ? 



Lumbar Plexus (Plexus lumbalis). (Figs. 272 and 273.) 



Eemove by blunt dissection the M. psoas major and expose 

 the lumbar plexus, preserving carefully the nerves derived from 

 it. (Cf. Toldt, Fig. 1327.) Study- 



(a) Muscular branches (rami musculares} . 



(b) Iliohypogastric nerve (N. iliohypogastricus). 



(ba) Muscular rami (rami musculares). 



(bb) Lateral cutaneous ramus (R. cutarieus lateralis). 

 (be) Anterior cutaneous ramus (R. cutaneus anterior). 



(c) Ilio-inguinal nerve (N. ilio-inguinalis) . 



(ca) Muscular branches (rami musculares). 



(cb) Anterior scrotal nerves (Nn. scrotales anteriores). 

 or Anterior labial nerves (Nn. labiales anteriores). 



(d) Genitofemoral nerve (N. genitofemoralis) (0. T. genitocrural). 



(da) Lumbo-inguinal nerve (N. lumbo-inguinalis) (0. T. crural 



branch). 



(db) External spermatic nerve (N. spermaticus externus) (0. T. 



genital branch). 



(e) Lateral cutaneous nerve of thigh (N. cutaneus femoris lateralis) (0. 



T. external cutaneous). 

 (/) Obturator nerve (N. obturatorius) . 



(fa) Anterior branch (ramus anterior). 



(fb) Posterior branch (ramus posterior). 



