Charles F. W. McClure. args) 
Between the sinus venosus and the point where it receives the right an- 
terior revehent vein (hepatico-subcardinal junction, Text. Fig. 11) the 
postcava, at its cranial end, occupies a position ventral to the right lung 
(Fig. 31, Plate IL), and further caudad is embedded in the liver. Here 
it receives the following tributaries (Text Fig. 10): (a) One or two 
DUCT OF CUVIER 
URORSEIS THORACIC 
AZYGOS 
POSTCARDINAL 
POSTCARDINAL 
POSTCAVA 
RIGHT 
ANT. REVEHENT 
VEIN 
LECT SUBCARDINAL 
ANT. REVEHENT 
VEIN 
SUBCARDINAL HEPATICO-SUBCARDINAL 
JUNCTION 
POSTCAVA 
PARS SUBCARDINALIS 
MESONEPHRIC 
VEINS 
CROSS 
ANASTOMOSIS 
POST. REVEHENT 
AF VEIN 
LEFT ; IN 
KIDNEY SUBCARDINAL 
POSTCARDINAL 
POSTCARDINAL 
VENOUS RING 
URETER 
Iniges bile 
Fic. 11. Dorsal view of the venous system of an 8 mm. embryo of Didel- 
phys. Semi-diagrammatic. 
hepatic veins from the right side of the liver (V. hepatica revehens 
dextra) ; (b) a large hepatic vein from the left side of the liver (VY. 
hepatica revehens sinistra) which opens into the postcava in common 
with the hepatic continuation of the umbilical veins; (c) the continuation 
of the omphalomesenteric vein which, after tunnelling the liver, opens 
into the postcava independently of the umbilical veins and finally, (d) a 
number of small hepatic veins which open at irregular intervals. Be- 
