SG Heritage Dictionary

Calypter [Noun] Webster's Dictionary 1828

1. The calyx of mosses, according to Linne; but not properly a calyx. It is a kind of vail, or cowl, which cove or is suspended over the tops of the stamens, like an extinguisher.

2. The calyptra of mosses is an appendage of the capsule or female flower. It at first closely invests the capsule, and its summit is the stigma. As the capsule approaches maturity, the calyptra is detached below, and appended to the stigma like a hood.