Description
The heart of a frog (Rana esculenta) from the back. Labels: s.v., sinus venosus opened; c.s.s., left vena cava superior; c.s.d., right vena cava superior; c.i., vena cava inferior; v.p., vena pulmonales; A.d., right auricle; A.s., left auricle; A.p., opening of communication between the right auricle and the sinus venosus.
