Today, the typical feather consists of a central shaft, called a rachis, with serial paired barbs forming a flat, curved surface, which is called a vane.

今天，典型的毛包含一个中心（称），还有连续成对的支形成平坦弯曲的表，这被称叶片。

The central part of the feather became a hardened structure called a rachis, with lots of little barbs and barbules, creating the vanes of the feather.

毛的中央部分变成了一种称的硬化结构，有许多小倒钩和小枝，形成了毛的叶片。

So where you see a typical flight feather that has a closed vein and an offset rachis to give it an aerodynamic airfoil shape, the ostrich is have done away with that completely.

所以如你所见这是一个典型的飞行毛，有一个封闭的静脉和一个偏移的给它一个符合空气动力学的翼型形状，鸵鸟已经完全失去了这种毛了。