Septum intermedium

Septum intermedium
Interior of dorsal half of heart of human embryo of about thirty-five days.
Same heart as in Fig. 467, opened on right side.
Details
Days	35
Anatomical terminology []

Endocardial cushions project into the atrial canal, and, meeting in the middle line, unite to form the septum intermedium which divides the canal into two channels, the future right and left atrioventricular orifices.

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)