ENDOSTOMIAL ARCHITECTURE IN DIPLOLEPIDEOUS MOSSES

Abstract

  A survey of endostome morphology in 70 species representing the diplolepideous orders Funariales, Bryales, Hypnobryales, lsobryales, Orthotrichales, and Hookeriales indicates that endostomes generally, if not always, consist of two layers of cell wall material. Cell patterns characteristic of the inner and outer endostome surfaces differ significantly, but each surface shows a remarkably uniform pattern among diplolepideous mosses with alternate segments. The endostome of Funaria is most similar to derived bryoid types that lack cilia and is probably not ancestral to but rather derived from such bryoid endostomes. Seemingly unique endostomes, as are found in the Timmiaceae and Orthothrichaceae, probably represent relatively minor modifications of the basic bryoid type.