用光镜观察了第15、17、19期鸡胚(H-H分期法)连续切片的心房和心室壁,并用计算机测量和计算了心内膜,心肌膜内、外表面的平均周长和表面积.第15期,心室小梁尚未形成,虽然心室壁的心内膜数值小于心肌膜,但心肌膜内表面的数值却大于外表面.第17、19期,已可见小梁结构,心内膜和心肌膜内表面的数值均大于心肌膜外表面.心房壁无小梁形成,各期数值均为内层小于外层.小梁形成前心肌膜内表面数值大于外表面的现象提示:小梁形成很可能首先与心肌膜内层有关. The atrium and ventricular wall of serial sections of chicken embryos (HH staging) in the 15 th, 17 th, and 19th stages were observed with light microscope. The average perimeter and surface area of ​​the endocardium, the inner membrane and the outer surface of the myocardium were measured and calculated by computer. 15th, the ventricular trabeculae have not yet formed, although the value of the endocardium of the ventricular wall is less than the myocardial membrane, the value of the inner surface of the myocardial membrane is larger than the outer surface.Phase 17,19, visible trabecular structure, endocardium and Myocardial membrane surface values ​​?? are greater than the outer surface of the myocardial membrane.Atrial wall trabecular formation, the value of the inner layer is less than the outer layer.The surface of the myocardial membrane before trabeculation is greater than the outer surface of the value of the phenomenon: Trabecular formation It is probably related to the inner layer of myocardial membrane first.