nexine
内层
[植] 外壁内层
例句
The nexine is much thicker.
外壁内层较为厚实。
The nexine is thicker, but the structure of the bacula becomes hardly differentiation, it looks like sponge as a whole.
外壁内层较为厚实 ，但柱状结构分化不明显 ，整体呈海绵状 ；
