定義： A landform that extends above the surrounding terrain in a limited area. A mountain is generally steeper than a hill, but there is no universally accepted standard definition for the height of a mountain or a hill although a mountain usually has an identifiable summit and a local relief of more than 300m.
定義： In the haploid (gametophyte) lifestage of a moss or fern, the antheridia (male) and archegonia (female) reproductive organs occur on the same individual plant. They may be borne on different shoots (autoicous), on the same shoot but not together in a common structure (paroicous), or together in a common "inflorescence" (synoicous).
