peristome

/per-uh-stohm/US // ˈpɛr əˌstoʊm //UK // (ˈpɛrɪˌstəʊm) //

蠕变体,蠕变体周围,蠕变体周边,蠕变体周长

Definitions

n.名词 noun

1
- : Botany. the one or two circles of small, pointed, toothlike appendages around the orifice of a capsule or urn of mosses, appearing when the lid is removed.
- : Zoology. any of various structures or sets of parts that surround or form the walls of a mouth or mouthlike opening.

The “mouth” or peristome is normally black, the shell larger and stouter than hortensis, in which the mouth is white.
The inner lip is that side of the peristome adjacent to the central pillar of the shell.
The capsules of the mosses form very beautiful microscopic objects, especially those furnished with a toothed peristome.
The capsule (fig. 5) is roundish-ovate, without a peristome, and the operculum is flattened.
In this moss the peristome is single (fig. 18), consisting of thirty-two spirally twisted teeth, arranged in pairs.