hymenium的复数形式怎么写？

These are covered in the spore - bearing layer ( hymenium ).子实 层生于菌褶的两面....

hymenium的音标：hymenium的英式发音音标为：[haɪ'mi:nɪəm]hymenium的美式发音音标为：[haɪ'minɪrm]...

n.子实层，子囊层...