292 The Development of the Postcaval Vein in Birds 
During the process of development the right lobe of the liver enlarges 
and grows backward, and thus includes the portion of the posteava 
which was at first situated in the caval mesentery and which is desig- 
nated in Fig. 7 as pars hepatica (V. c. i. H.). 
A.o.m.d. 
\ 
N 
“N 
Vhr 
Fie. 7. Reconstruction of the venous system of a sparrow embryo, cor- 
responding to a chick of about 14 days. Ventral view. X 30. (Explanation 
of lettering on page 284.) 
In Fig. 7 (sparrow, corresponding to a chick of 14 days’ incubation) 
the subeardinal portion of the posteava (V. c. i. SC.) is seen to be rela- 
tively small, the mesonephros having diminished to an unimportant 
