1893.] - Lateroversion of the Ophidian Heart. 863 
dorsal than lateral has, on account of the rotation, assumed a 
more nearly mesial and ventral location, thus bringing the 
posteava in line with the pulmonary vein to which it seemed 
tobe quite closely adherent. 'The left jugular vein likewise 
presents a central enlargement and forms a sling-like support 
for the arch of the left aorta. 
TER 
In the intricate and unusual arrangement of the parts here, 
the vein was inadvertently cut so that its course to the right 
auricle could not be satisfactorily determined. 
The pulmonary vein passes from the lung through the 
pericardial cavity accompanied by the post-cava and passes 
between the two auricles more ventral than dorsal and enters 
the left auricle. : 
The significance of the central enlargements of the left 
aorta and the carotid artery and of the left and right jugular 
