They had these bone plates that formed its skin.

它们的骨构成了表皮。

These neurons migrate down from the olfactory placode and get embedded in the cribriform plate, which is a bone plate that separates the nasal cavity from the brain, forming the olfactory bulb.

这些神经元从嗅觉基板迁移下来，并嵌入筛板中，即将鼻腔与大脑隔开的骨板，从而形成嗅球。