1984 Volume 57 Pages 285-298
During this century, the moss peristome has emerged as a most useful structure for inferring phylogenetic relationships because of the conservative nature of its variation. In the Bryaceae however, peristome structure varies extensively between and within genera, and sometimes within species. A trend of progressively more reduced peristome types in the genus Anomobryum is exemplified by five species discussed in this paper: A. filiforme, A. promontorii, A. sharpii (spec. nov.), A. ochianum (spec. nov.), and A. tereticaulis (n. comb.). The exostome and endostome may become modified independently of one another and do not seem to function as an integrated adaptive unit.